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7056c4e2a1
2587 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Paolo Bonzini
|
ab978c62e7 |
Merge branch 'kvm-6.11-sev-snp' into HEAD
Pull base x86 KVM support for running SEV-SNP guests from Michael Roth: * add some basic infrastructure and introduces a new KVM_X86_SNP_VM vm_type to handle differences versus the existing KVM_X86_SEV_VM and KVM_X86_SEV_ES_VM types. * implement the KVM API to handle the creation of a cryptographic launch context, encrypt/measure the initial image into guest memory, and finalize it before launching it. * implement handling for various guest-generated events such as page state changes, onlining of additional vCPUs, etc. * implement the gmem/mmu hooks needed to prepare gmem-allocated pages before mapping them into guest private memory ranges as well as cleaning them up prior to returning them to the host for use as normal memory. Because those cleanup hooks supplant certain activities like issuing WBINVDs during KVM MMU invalidations, avoid duplicating that work to avoid unecessary overhead. This merge leaves out support support for attestation guest requests and for loading the signing keys to be used for attestation requests. |
||
Sean Christopherson
|
778c350eb5 |
Revert "KVM: async_pf: avoid recursive flushing of work items"
Now that KVM does NOT gift async #PF workers a "struct kvm" reference,
don't bother skipping "done" workers when flushing/canceling queued
workers, as the deadlock that was being fudged around can no longer occur.
When workers, i.e. async_pf_execute(), were gifted a referenced, it was
possible for a worker to put the last reference and trigger VM destruction,
i.e. trigger flushing of a workqueue from a worker in said workqueue.
Note, there is no actual lock, the deadlock was that a worker will be
stuck waiting for itself (the workqueue code simulates a lock/unlock via
lock_map_{acquire,release}()).
Skipping "done" workers isn't problematic per se, but using work->vcpu as
a "done" flag is confusing, e.g. it's not clear that async_pf.lock is
acquired to protect the work->vcpu, NOT the processing of async_pf.queue
(which is protected by vcpu->mutex).
This reverts commit
|
||
Parshuram Sangle
|
aeb1b22a3a |
KVM: Enable halt polling shrink parameter by default
Default halt_poll_ns_shrink value of 0 always resets polling interval to 0 on an un-successful poll where vcpu wakeup is not received. This is mostly to avoid pointless polling for more number of shorter intervals. But disabled shrink assumes vcpu wakeup is less likely to be received in subsequent shorter polling intervals. Another side effect of 0 shrink value is that, even on a successful poll if total block time was greater than current polling interval, the polling interval starts over from 0 instead of shrinking by a factor. Enabling shrink with value of 2 allows the polling interval to gradually decrement in case of un-successful poll events as well. This gives a fair chance for successful polling events in subsequent polling intervals rather than resetting it to 0 and starting over from grow_start. Below kvm stat log snippet shows interleaved growth and shrinking of polling interval: 87162647182125: kvm_halt_poll_ns: vcpu 0: halt_poll_ns 10000 (grow 0) 87162647637763: kvm_halt_poll_ns: vcpu 0: halt_poll_ns 20000 (grow 10000) 87162649627943: kvm_halt_poll_ns: vcpu 0: halt_poll_ns 40000 (grow 20000) 87162650892407: kvm_halt_poll_ns: vcpu 0: halt_poll_ns 20000 (shrink 40000) 87162651540378: kvm_halt_poll_ns: vcpu 0: halt_poll_ns 40000 (grow 20000) 87162652276768: kvm_halt_poll_ns: vcpu 0: halt_poll_ns 20000 (shrink 40000) 87162652515037: kvm_halt_poll_ns: vcpu 0: halt_poll_ns 40000 (grow 20000) 87162653383787: kvm_halt_poll_ns: vcpu 0: halt_poll_ns 20000 (shrink 40000) 87162653627670: kvm_halt_poll_ns: vcpu 0: halt_poll_ns 10000 (shrink 20000) 87162653796321: kvm_halt_poll_ns: vcpu 0: halt_poll_ns 20000 (grow 10000) 87162656171645: kvm_halt_poll_ns: vcpu 0: halt_poll_ns 10000 (shrink 20000) 87162661607487: kvm_halt_poll_ns: vcpu 0: halt_poll_ns 0 (shrink 10000) Having both grow and shrink enabled creates a balance in polling interval growth and shrink behavior. Tests show improved successful polling attempt ratio which contribute to VM performance. Power penalty is quite negligible as shrunk polling intervals create bursts of very short durations. Performance assessment results show 3-6% improvements in CPU+GPU, Memory and Storage Android VM workloads whereas 5-9% improvement in average FPS of gaming VM workloads. Power penalty is below 1% where host OS is either idle or running a native workload having 2 VMs enabled. CPU/GPU intensive gaming workloads as well do not show any increased power overhead with shrink enabled. Co-developed-by: Rajendran Jaishankar <jaishankar.rajendran@intel.com> Signed-off-by: Rajendran Jaishankar <jaishankar.rajendran@intel.com> Signed-off-by: Parshuram Sangle <parshuram.sangle@intel.com> Link: https://lore.kernel.org/r/20231102154628.2120-2-parshuram.sangle@intel.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
Borislav Petkov
|
96a02b9fa9 |
KVM: Unexport kvm_debugfs_dir
After
|
||
Linus Torvalds
|
61307b7be4 |
The usual shower of singleton fixes and minor series all over MM,
documented (hopefully adequately) in the respective changelogs. Notable
series include:
- Lucas Stach has provided some page-mapping
cleanup/consolidation/maintainability work in the series "mm/treewide:
Remove pXd_huge() API".
- In the series "Allow migrate on protnone reference with
MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
MPOL_PREFERRED_MANY mode, yielding almost doubled performance in one
test.
- In their series "Memory allocation profiling" Kent Overstreet and
Suren Baghdasaryan have contributed a means of determining (via
/proc/allocinfo) whereabouts in the kernel memory is being allocated:
number of calls and amount of memory.
- Matthew Wilcox has provided the series "Various significant MM
patches" which does a number of rather unrelated things, but in largely
similar code sites.
- In his series "mm: page_alloc: freelist migratetype hygiene" Johannes
Weiner has fixed the page allocator's handling of migratetype requests,
with resulting improvements in compaction efficiency.
- In the series "make the hugetlb migration strategy consistent" Baolin
Wang has fixed a hugetlb migration issue, which should improve hugetlb
allocation reliability.
- Liu Shixin has hit an I/O meltdown caused by readahead in a
memory-tight memcg. Addressed in the series "Fix I/O high when memory
almost met memcg limit".
- In the series "mm/filemap: optimize folio adding and splitting" Kairui
Song has optimized pagecache insertion, yielding ~10% performance
improvement in one test.
- Baoquan He has cleaned up and consolidated the early zone
initialization code in the series "mm/mm_init.c: refactor
free_area_init_core()".
- Baoquan has also redone some MM initializatio code in the series
"mm/init: minor clean up and improvement".
- MM helper cleanups from Christoph Hellwig in his series "remove
follow_pfn".
- More cleanups from Matthew Wilcox in the series "Various page->flags
cleanups".
- Vlastimil Babka has contributed maintainability improvements in the
series "memcg_kmem hooks refactoring".
- More folio conversions and cleanups in Matthew Wilcox's series
"Convert huge_zero_page to huge_zero_folio"
"khugepaged folio conversions"
"Remove page_idle and page_young wrappers"
"Use folio APIs in procfs"
"Clean up __folio_put()"
"Some cleanups for memory-failure"
"Remove page_mapping()"
"More folio compat code removal"
- David Hildenbrand chipped in with "fs/proc/task_mmu: convert hugetlb
functions to work on folis".
- Code consolidation and cleanup work related to GUP's handling of
hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".
- Rick Edgecombe has developed some fixes to stack guard gaps in the
series "Cover a guard gap corner case".
- Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the series
"mm/ksm: fix ksm exec support for prctl".
- Baolin Wang has implemented NUMA balancing for multi-size THPs. This
is a simple first-cut implementation for now. The series is "support
multi-size THP numa balancing".
- Cleanups to vma handling helper functions from Matthew Wilcox in the
series "Unify vma_address and vma_pgoff_address".
- Some selftests maintenance work from Dev Jain in the series
"selftests/mm: mremap_test: Optimizations and style fixes".
- Improvements to the swapping of multi-size THPs from Ryan Roberts in
the series "Swap-out mTHP without splitting".
- Kefeng Wang has significantly optimized the handling of arm64's
permission page faults in the series
"arch/mm/fault: accelerate pagefault when badaccess"
"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"
- GUP cleanups from David Hildenbrand in "mm/gup: consistently call it
GUP-fast".
- hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault path to
use struct vm_fault".
- selftests build fixes from John Hubbard in the series "Fix
selftests/mm build without requiring "make headers"".
- Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
series "Improved Memory Tier Creation for CPUless NUMA Nodes". Fixes
the initialization code so that migration between different memory types
works as intended.
- David Hildenbrand has improved follow_pte() and fixed an errant driver
in the series "mm: follow_pte() improvements and acrn follow_pte()
fixes".
- David also did some cleanup work on large folio mapcounts in his
series "mm: mapcount for large folios + page_mapcount() cleanups".
- Folio conversions in KSM in Alex Shi's series "transfer page to folio
in KSM".
- Barry Song has added some sysfs stats for monitoring multi-size THP's
in the series "mm: add per-order mTHP alloc and swpout counters".
- Some zswap cleanups from Yosry Ahmed in the series "zswap same-filled
and limit checking cleanups".
- Matthew Wilcox has been looking at buffer_head code and found the
documentation to be lacking. The series is "Improve buffer head
documentation".
- Multi-size THPs get more work, this time from Lance Yang. His series
"mm/madvise: enhance lazyfreeing with mTHP in madvise_free" optimizes
the freeing of these things.
- Kemeng Shi has added more userspace-visible writeback instrumentation
in the series "Improve visibility of writeback".
- Kemeng Shi then sent some maintenance work on top in the series "Fix
and cleanups to page-writeback".
- Matthew Wilcox reduces mmap_lock traffic in the anon vma code in the
series "Improve anon_vma scalability for anon VMAs". Intel's test bot
reported an improbable 3x improvement in one test.
- SeongJae Park adds some DAMON feature work in the series
"mm/damon: add a DAMOS filter type for page granularity access recheck"
"selftests/damon: add DAMOS quota goal test"
- Also some maintenance work in the series
"mm/damon/paddr: simplify page level access re-check for pageout"
"mm/damon: misc fixes and improvements"
- David Hildenbrand has disabled some known-to-fail selftests ni the
series "selftests: mm: cow: flag vmsplice() hugetlb tests as XFAIL".
- memcg metadata storage optimizations from Shakeel Butt in "memcg:
reduce memory consumption by memcg stats".
- DAX fixes and maintenance work from Vishal Verma in the series
"dax/bus.c: Fixups for dax-bus locking".
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Merge tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull mm updates from Andrew Morton:
"The usual shower of singleton fixes and minor series all over MM,
documented (hopefully adequately) in the respective changelogs.
Notable series include:
- Lucas Stach has provided some page-mapping cleanup/consolidation/
maintainability work in the series "mm/treewide: Remove pXd_huge()
API".
- In the series "Allow migrate on protnone reference with
MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
MPOL_PREFERRED_MANY mode, yielding almost doubled performance in
one test.
- In their series "Memory allocation profiling" Kent Overstreet and
Suren Baghdasaryan have contributed a means of determining (via
/proc/allocinfo) whereabouts in the kernel memory is being
allocated: number of calls and amount of memory.
- Matthew Wilcox has provided the series "Various significant MM
patches" which does a number of rather unrelated things, but in
largely similar code sites.
- In his series "mm: page_alloc: freelist migratetype hygiene"
Johannes Weiner has fixed the page allocator's handling of
migratetype requests, with resulting improvements in compaction
efficiency.
- In the series "make the hugetlb migration strategy consistent"
Baolin Wang has fixed a hugetlb migration issue, which should
improve hugetlb allocation reliability.
- Liu Shixin has hit an I/O meltdown caused by readahead in a
memory-tight memcg. Addressed in the series "Fix I/O high when
memory almost met memcg limit".
- In the series "mm/filemap: optimize folio adding and splitting"
Kairui Song has optimized pagecache insertion, yielding ~10%
performance improvement in one test.
- Baoquan He has cleaned up and consolidated the early zone
initialization code in the series "mm/mm_init.c: refactor
free_area_init_core()".
- Baoquan has also redone some MM initializatio code in the series
"mm/init: minor clean up and improvement".
- MM helper cleanups from Christoph Hellwig in his series "remove
follow_pfn".
- More cleanups from Matthew Wilcox in the series "Various
page->flags cleanups".
- Vlastimil Babka has contributed maintainability improvements in the
series "memcg_kmem hooks refactoring".
- More folio conversions and cleanups in Matthew Wilcox's series:
"Convert huge_zero_page to huge_zero_folio"
"khugepaged folio conversions"
"Remove page_idle and page_young wrappers"
"Use folio APIs in procfs"
"Clean up __folio_put()"
"Some cleanups for memory-failure"
"Remove page_mapping()"
"More folio compat code removal"
- David Hildenbrand chipped in with "fs/proc/task_mmu: convert
hugetlb functions to work on folis".
- Code consolidation and cleanup work related to GUP's handling of
hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".
- Rick Edgecombe has developed some fixes to stack guard gaps in the
series "Cover a guard gap corner case".
- Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the
series "mm/ksm: fix ksm exec support for prctl".
- Baolin Wang has implemented NUMA balancing for multi-size THPs.
This is a simple first-cut implementation for now. The series is
"support multi-size THP numa balancing".
- Cleanups to vma handling helper functions from Matthew Wilcox in
the series "Unify vma_address and vma_pgoff_address".
- Some selftests maintenance work from Dev Jain in the series
"selftests/mm: mremap_test: Optimizations and style fixes".
- Improvements to the swapping of multi-size THPs from Ryan Roberts
in the series "Swap-out mTHP without splitting".
- Kefeng Wang has significantly optimized the handling of arm64's
permission page faults in the series
"arch/mm/fault: accelerate pagefault when badaccess"
"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"
- GUP cleanups from David Hildenbrand in "mm/gup: consistently call
it GUP-fast".
- hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault
path to use struct vm_fault".
- selftests build fixes from John Hubbard in the series "Fix
selftests/mm build without requiring "make headers"".
- Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
series "Improved Memory Tier Creation for CPUless NUMA Nodes".
Fixes the initialization code so that migration between different
memory types works as intended.
- David Hildenbrand has improved follow_pte() and fixed an errant
driver in the series "mm: follow_pte() improvements and acrn
follow_pte() fixes".
- David also did some cleanup work on large folio mapcounts in his
series "mm: mapcount for large folios + page_mapcount() cleanups".
- Folio conversions in KSM in Alex Shi's series "transfer page to
folio in KSM".
- Barry Song has added some sysfs stats for monitoring multi-size
THP's in the series "mm: add per-order mTHP alloc and swpout
counters".
- Some zswap cleanups from Yosry Ahmed in the series "zswap
same-filled and limit checking cleanups".
- Matthew Wilcox has been looking at buffer_head code and found the
documentation to be lacking. The series is "Improve buffer head
documentation".
- Multi-size THPs get more work, this time from Lance Yang. His
series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free"
optimizes the freeing of these things.
- Kemeng Shi has added more userspace-visible writeback
instrumentation in the series "Improve visibility of writeback".
- Kemeng Shi then sent some maintenance work on top in the series
"Fix and cleanups to page-writeback".
- Matthew Wilcox reduces mmap_lock traffic in the anon vma code in
the series "Improve anon_vma scalability for anon VMAs". Intel's
test bot reported an improbable 3x improvement in one test.
- SeongJae Park adds some DAMON feature work in the series
"mm/damon: add a DAMOS filter type for page granularity access recheck"
"selftests/damon: add DAMOS quota goal test"
- Also some maintenance work in the series
"mm/damon/paddr: simplify page level access re-check for pageout"
"mm/damon: misc fixes and improvements"
- David Hildenbrand has disabled some known-to-fail selftests ni the
series "selftests: mm: cow: flag vmsplice() hugetlb tests as
XFAIL".
- memcg metadata storage optimizations from Shakeel Butt in "memcg:
reduce memory consumption by memcg stats".
- DAX fixes and maintenance work from Vishal Verma in the series
"dax/bus.c: Fixups for dax-bus locking""
* tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits)
memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order
selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault
selftests: cgroup: add tests to verify the zswap writeback path
mm: memcg: make alloc_mem_cgroup_per_node_info() return bool
mm/damon/core: fix return value from damos_wmark_metric_value
mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED
selftests: cgroup: remove redundant enabling of memory controller
Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree
Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT
Docs/mm/damon/design: use a list for supported filters
Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command
Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file
selftests/damon: classify tests for functionalities and regressions
selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None'
selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts
selftests/damon/_damon_sysfs: check errors from nr_schemes file reads
mm/damon/core: initialize ->esz_bp from damos_quota_init_priv()
selftests/damon: add a test for DAMOS quota goal
...
|
||
Michael Roth
|
4f2e7aa1cf |
KVM: SEV: Implement gmem hook for initializing private pages
This will handle the RMP table updates needed to put a page into a private state before mapping it into an SEV-SNP guest. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Message-ID: <20240501085210.2213060-14-michael.roth@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Paolo Bonzini
|
7323260373 |
Merge branch 'kvm-coco-hooks' into HEAD
Common patches for the target-independent functionality and hooks that are needed by SEV-SNP and TDX. |
||
|
Paolo Bonzini
|
7d41e24da2 |
KVM x86 misc changes for 6.10:
- Advertise the max mappable GPA in the "guest MAXPHYADDR" CPUID field, which
is unused by hardware, so that KVM can communicate its inability to map GPAs
that set bits 51:48 due to lack of 5-level paging. Guest firmware is
expected to use the information to safely remap BARs in the uppermost GPA
space, i.e to avoid placing a BAR at a legal, but unmappable, GPA.
- Use vfree() instead of kvfree() for allocations that always use vcalloc()
or __vcalloc().
- Don't completely ignore same-value writes to immutable feature MSRs, as
doing so results in KVM failing to reject accesses to MSR that aren't
supposed to exist given the vCPU model and/or KVM configuration.
- Don't mark APICv as being inhibited due to ABSENT if APICv is disabled
KVM-wide to avoid confusing debuggers (KVM will never bother clearing the
ABSENT inhibit, even if userspace enables in-kernel local APIC).
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Merge tag 'kvm-x86-misc-6.10' of https://github.com/kvm-x86/linux into HEAD
KVM x86 misc changes for 6.10:
- Advertise the max mappable GPA in the "guest MAXPHYADDR" CPUID field, which
is unused by hardware, so that KVM can communicate its inability to map GPAs
that set bits 51:48 due to lack of 5-level paging. Guest firmware is
expected to use the information to safely remap BARs in the uppermost GPA
space, i.e to avoid placing a BAR at a legal, but unmappable, GPA.
- Use vfree() instead of kvfree() for allocations that always use vcalloc()
or __vcalloc().
- Don't completely ignore same-value writes to immutable feature MSRs, as
doing so results in KVM failing to reject accesses to MSR that aren't
supposed to exist given the vCPU model and/or KVM configuration.
- Don't mark APICv as being inhibited due to ABSENT if APICv is disabled
KVM-wide to avoid confusing debuggers (KVM will never bother clearing the
ABSENT inhibit, even if userspace enables in-kernel local APIC).
|
||
|
Paolo Bonzini
|
f4bc1373d5 |
KVM cleanups for 6.10:
- Misc cleanups extracted from the "exit on missing userspace mapping" series,
which has been put on hold in anticipation of a "KVM Userfault" approach,
which should provide a superset of functionality.
- Remove kvm_make_all_cpus_request_except(), which got added to hack around an
AVIC bug, and then became dead code when a more robust fix came along.
- Fix a goof in the KVM_CREATE_GUEST_MEMFD documentation.
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Merge tag 'kvm-x86-generic-6.10' of https://github.com/kvm-x86/linux into HEAD
KVM cleanups for 6.10:
- Misc cleanups extracted from the "exit on missing userspace mapping" series,
which has been put on hold in anticipation of a "KVM Userfault" approach,
which should provide a superset of functionality.
- Remove kvm_make_all_cpus_request_except(), which got added to hack around an
AVIC bug, and then became dead code when a more robust fix came along.
- Fix a goof in the KVM_CREATE_GUEST_MEMFD documentation.
|
||
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Paolo Bonzini
|
e5f62e27b1 |
KVM/arm64 updates for Linux 6.10
- Move a lot of state that was previously stored on a per vcpu basis into a per-CPU area, because it is only pertinent to the host while the vcpu is loaded. This results in better state tracking, and a smaller vcpu structure. - Add full handling of the ERET/ERETAA/ERETAB instructions in nested virtualisation. The last two instructions also require emulating part of the pointer authentication extension. As a result, the trap handling of pointer authentication has been greattly simplified. - Turn the global (and not very scalable) LPI translation cache into a per-ITS, scalable cache, making non directly injected LPIs much cheaper to make visible to the vcpu. - A batch of pKVM patches, mostly fixes and cleanups, as the upstreaming process seems to be resuming. Fingers crossed! - Allocate PPIs and SGIs outside of the vcpu structure, allowing for smaller EL2 mapping and some flexibility in implementing more or less than 32 private IRQs. - Purge stale mpidr_data if a vcpu is created after the MPIDR map has been created. - Preserve vcpu-specific ID registers across a vcpu reset. - Various minor cleanups and improvements. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAmY/PT4ACgkQI9DQutE9 ekNwSA/7BTro0n5gP5/SfSFJeEedigpmHQJtHJk9og0LBzjXZTvYqKpI5J1HnpWE AFsDf3aDRPaSCvI+S14LkkK+TmGtVEXUg8YGytQo08IcO2x6xBT/YjpkVOHy23kq SGgNMPNUH2sycb7hTcz9Z/V0vBeYwFzYEAhmpvtROvmaRd8ZIyt+ofcclwUZZAQ2 SolOXR2d+ynCh8ZCOexqyZ67keikW1NXtW5aNWWFc6S6qhmcWdaWJGDcSyHauFac +YuHjPETJYh7TNpwYTmKclRh1fk/CgA/e+r71Hlgdkg+DGCyVnEZBQxqMi6GTzNC dzy3qhTtRT61SR54q55yMVIC3o6uRSkht+xNg1Nd+UghiqGKAtoYhvGjduodONW2 1Eas6O+vHipu98HgFnkJRPlnF1HR3VunPDwpzIWIZjK0fIXEfrWqCR3nHFaxShOR dniTEPfELguxOtbl3jCZ+KHCIXueysczXFlqQjSDkg/P1l0jKBgpkZzMPY2mpP1y TgjipfSL5gr1GPdbrmh4WznQtn5IYWduKIrdEmSBuru05OmBaCO4geXPUwL4coHd O8TBnXYBTN/z3lORZMSOj9uK8hgU1UWmnOIkdJ4YBBAL8DSS+O+KtCRkHQP0ghl+ whl0q1SWTu4LtOQzN5CUrhq9Tge11erEt888VyJbBJmv8x6qJjE= =CEfD -----END PGP SIGNATURE----- Merge tag 'kvmarm-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for Linux 6.10 - Move a lot of state that was previously stored on a per vcpu basis into a per-CPU area, because it is only pertinent to the host while the vcpu is loaded. This results in better state tracking, and a smaller vcpu structure. - Add full handling of the ERET/ERETAA/ERETAB instructions in nested virtualisation. The last two instructions also require emulating part of the pointer authentication extension. As a result, the trap handling of pointer authentication has been greattly simplified. - Turn the global (and not very scalable) LPI translation cache into a per-ITS, scalable cache, making non directly injected LPIs much cheaper to make visible to the vcpu. - A batch of pKVM patches, mostly fixes and cleanups, as the upstreaming process seems to be resuming. Fingers crossed! - Allocate PPIs and SGIs outside of the vcpu structure, allowing for smaller EL2 mapping and some flexibility in implementing more or less than 32 private IRQs. - Purge stale mpidr_data if a vcpu is created after the MPIDR map has been created. - Preserve vcpu-specific ID registers across a vcpu reset. - Various minor cleanups and improvements. |
||
|
Paolo Bonzini
|
4232da23d7 |
Merge tag 'loongarch-kvm-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD
LoongArch KVM changes for v6.10 1. Add ParaVirt IPI support. 2. Add software breakpoint support. 3. Add mmio trace events support. |
||
|
Michael Roth
|
a90764f0e4 |
KVM: guest_memfd: Add hook for invalidating memory
In some cases, like with SEV-SNP, guest memory needs to be updated in a platform-specific manner before it can be safely freed back to the host. Wire up arch-defined hooks to the .free_folio kvm_gmem_aops callback to allow for special handling of this sort when freeing memory in response to FALLOC_FL_PUNCH_HOLE operations and when releasing the inode, and go ahead and define an arch-specific hook for x86 since it will be needed for handling memory used for SEV-SNP guests. Signed-off-by: Michael Roth <michael.roth@amd.com> Message-Id: <20231230172351.574091-6-michael.roth@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Paolo Bonzini
|
1f6c06b177 |
KVM: guest_memfd: Add interface for populating gmem pages with user data
During guest run-time, kvm_arch_gmem_prepare() is issued as needed to prepare newly-allocated gmem pages prior to mapping them into the guest. In the case of SEV-SNP, this mainly involves setting the pages to private in the RMP table. However, for the GPA ranges comprising the initial guest payload, which are encrypted/measured prior to starting the guest, the gmem pages need to be accessed prior to setting them to private in the RMP table so they can be initialized with the userspace-provided data. Additionally, an SNP firmware call is needed afterward to encrypt them in-place and measure the contents into the guest's launch digest. While it is possible to bypass the kvm_arch_gmem_prepare() hooks so that this handling can be done in an open-coded/vendor-specific manner, this may expose more gmem-internal state/dependencies to external callers than necessary. Try to avoid this by implementing an interface that tries to handle as much of the common functionality inside gmem as possible, while also making it generic enough to potentially be usable/extensible for TDX as well. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Co-developed-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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|
Paolo Bonzini
|
17573fd971 |
KVM: guest_memfd: extract __kvm_gmem_get_pfn()
In preparation for adding a function that walks a set of pages provided by userspace and populates them in a guest_memfd, add a version of kvm_gmem_get_pfn() that has a "bool prepare" argument and passes it down to kvm_gmem_get_folio(). Populating guest memory has to call repeatedly __kvm_gmem_get_pfn() on the same file, so make the new function take struct file*. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Paolo Bonzini
|
3bb2531e20 |
KVM: guest_memfd: Add hook for initializing memory
guest_memfd pages are generally expected to be in some arch-defined initial state prior to using them for guest memory. For SEV-SNP this initial state is 'private', or 'guest-owned', and requires additional operations to move these pages into a 'private' state by updating the corresponding entries the RMP table. Allow for an arch-defined hook to handle updates of this sort, and go ahead and implement one for x86 so KVM implementations like AMD SVM can register a kvm_x86_ops callback to handle these updates for SEV-SNP guests. The preparation callback is always called when allocating/grabbing folios via gmem, and it is up to the architecture to keep track of whether or not the pages are already in the expected state (e.g. the RMP table in the case of SEV-SNP). In some cases, it is necessary to defer the preparation of the pages to handle things like in-place encryption of initial guest memory payloads before marking these pages as 'private'/'guest-owned'. Add an argument (always true for now) to kvm_gmem_get_folio() that allows for the preparation callback to be bypassed. To detect possible issues in the way userspace initializes memory, it is only possible to add an unprepared page if it is not already included in the filemap. Link: https://lore.kernel.org/lkml/ZLqVdvsF11Ddo7Dq@google.com/ Co-developed-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Message-Id: <20231230172351.574091-5-michael.roth@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Paolo Bonzini
|
fa30b0dc91 |
KVM: guest_memfd: limit overzealous WARN
Because kvm_gmem_get_pfn() is called from the page fault path without any of the slots_lock, filemap lock or mmu_lock taken, it is possible for it to race with kvm_gmem_unbind(). This is not a problem, as any PTE that is installed temporarily will be zapped before the guest has the occasion to run. However, it is not possible to have a complete unbind+bind racing with the page fault, because deleting the memslot will call synchronize_srcu_expedited() and wait for the page fault to be resolved. Thus, we can still warn if the file is there and is not the one we expect. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Paolo Bonzini
|
7062372377 |
KVM: guest_memfd: pass error up from filemap_grab_folio
Some SNP ioctls will require the page not to be in the pagecache, and as such they will want to return EEXIST to userspace. Start by passing the error up from filemap_grab_folio. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Michael Roth
|
1d23040caa |
KVM: guest_memfd: Use AS_INACCESSIBLE when creating guest_memfd inode
truncate_inode_pages_range() may attempt to zero pages before truncating them, and this will occur before arch-specific invalidations can be triggered via .invalidate_folio/.free_folio hooks via kvm_gmem_aops. For AMD SEV-SNP this would result in an RMP #PF being generated by the hardware, which is currently treated as fatal (and even if specifically allowed for, would not result in anything other than garbage being written to guest pages due to encryption). On Intel TDX this would also result in undesirable behavior. Set the AS_INACCESSIBLE flag to prevent the MM from attempting unexpected accesses of this sort during operations like truncation. This may also in some cases yield a decent performance improvement for guest_memfd userspace implementations that hole-punch ranges immediately after private->shared conversions via KVM_SET_MEMORY_ATTRIBUTES, since the current implementation of truncate_inode_pages_range() always ends up zero'ing an entire 4K range if it is backing by a 2M folio. Link: https://lore.kernel.org/lkml/ZR9LYhpxTaTk6PJX@google.com/ Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Message-ID: <20240329212444.395559-6-michael.roth@amd.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
David Hildenbrand
|
29ae7d96d1 |
mm: pass VMA instead of MM to follow_pte()
... and centralize the VM_IO/VM_PFNMAP sanity check in there. We'll now also perform these sanity checks for direct follow_pte() invocations. For generic_access_phys(), we might now check multiple times: nothing to worry about, really. Link: https://lkml.kernel.org/r/20240410155527.474777-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Sean Christopherson <seanjc@google.com> [KVM] Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Fei Li <fei1.li@intel.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Yonghua Huang <yonghua.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
Venkatesh Srinivas
|
82e9c84d87 |
KVM: Remove kvm_make_all_cpus_request_except()
Remove kvm_make_all_cpus_request_except() as it effectively has no users, and arguably should never have been added in the first place. Commit |
||
Oliver Upton
|
ea54dd3742 |
KVM: Treat the device list as an rculist
A subsequent change to KVM/arm64 will necessitate walking the device list outside of the kvm->lock. Prepare by converting to an rculist. This has zero effect on the VM destruction path, as it is expected every reader is backed by a reference on the kvm struct. On the other hand, ensure a given device is completely destroyed before dropping the kvm->lock in the release() path, as certain devices expect to be a singleton (e.g. the vfio-kvm device). Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Signed-off-by: Oliver Upton <oliver.upton@linux.dev> Reviewed-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/20240422200158.2606761-2-oliver.upton@linux.dev Signed-off-by: Marc Zyngier <maz@kernel.org> |
||
|
Sean Christopherson
|
c23e2b7103 |
KVM: Allow page-sized MMU caches to be initialized with custom 64-bit values
Add support to MMU caches for initializing a page with a custom 64-bit value, e.g. to pre-fill an entire page table with non-zero PTE values. The functionality will be used by x86 to support Intel's TDX, which needs to set bit 63 in all non-present PTEs in order to prevent !PRESENT page faults from getting reflected into the guest (Intel's EPT Violation #VE architecture made the less than brilliant decision of having the per-PTE behavior be opt-out instead of opt-in). Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Message-Id: <5919f685f109a1b0ebc6bd8fc4536ee94bcc172d.1705965635.git.isaku.yamahata@intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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|
Sean Christopherson
|
eefb85b3f0 |
KVM: Drop unused @may_block param from gfn_to_pfn_cache_invalidate_start()
Remove gfn_to_pfn_cache_invalidate_start()'s unused @may_block parameter,
which was leftover from KVM's abandoned (for now) attempt to support guest
usage of gfn_to_pfn caches.
Fixes:
|
||
|
Paolo Bonzini
|
5257de954c |
KVM: remove unused argument of kvm_handle_hva_range()
The only user was kvm_mmu_notifier_change_pte(), which is now gone. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Message-ID: <20240405115815.3226315-3-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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|
Paolo Bonzini
|
f3b65bbaed |
KVM: delete .change_pte MMU notifier callback
The .change_pte() MMU notifier callback was intended as an
optimization. The original point of it was that KSM could tell KVM to flip
its secondary PTE to a new location without having to first zap it. At
the time there was also an .invalidate_page() callback; both of them were
*not* bracketed by calls to mmu_notifier_invalidate_range_{start,end}(),
and .invalidate_page() also doubled as a fallback implementation of
.change_pte().
Later on, however, both callbacks were changed to occur within an
invalidate_range_start/end() block.
In the case of .change_pte(), commit
|
||
Anish Moorthy
|
f588557ac4 |
KVM: Simplify error handling in __gfn_to_pfn_memslot()
KVM_HVA_ERR_RO_BAD satisfies kvm_is_error_hva(), so there's no need to duplicate the "if (writable)" block. Fix this by bringing all kvm_is_error_hva() cases under one conditional. Signed-off-by: Anish Moorthy <amoorthy@google.com> Link: https://lore.kernel.org/r/20240215235405.368539-5-amoorthy@google.com [sean: use ternary operator] Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
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Anish Moorthy
|
a3bd2f7ead |
KVM: Add function comments for __kvm_read/write_guest_page()
The (gfn, data, offset, len) order of parameters is a little strange since "offset" applies to "gfn" rather than to "data". Add function comments to make things perfectly clear. Signed-off-by: Anish Moorthy <amoorthy@google.com> Link: https://lore.kernel.org/r/20240215235405.368539-3-amoorthy@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
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|
Anish Moorthy
|
ed2f049fc1 |
KVM: Clarify meaning of hva_to_pfn()'s 'atomic' parameter
The current description can be read as "atomic -> allowed to sleep," when in fact the intended statement is "atomic -> NOT allowed to sleep." Make that clearer in the docstring. Signed-off-by: Anish Moorthy <amoorthy@google.com> Link: https://lore.kernel.org/r/20240215235405.368539-2-amoorthy@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
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Li RongQing
|
a952d608f0 |
KVM: Use vfree for memory allocated by vcalloc()/__vcalloc()
commit 37b2a6510a48("KVM: use __vcalloc for very large allocations")
replaced kvzalloc()/kvcalloc() with vcalloc(), but didn't replace kvfree()
with vfree().
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Link: https://lore.kernel.org/r/20240131012357.53563-1-lirongqing@baidu.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
||
|
Sean Christopherson
|
fc62a4e8de |
KVM: Explicitly disallow activatating a gfn_to_pfn_cache with INVALID_GPA
Explicit disallow activating a gfn_to_pfn_cache with an error gpa, i.e. INVALID_GPA, to ensure that KVM doesn't mistake a GPA-based cache for an HVA-based cache (KVM uses INVALID_GPA as a magic value to differentiate between GPA-based and HVA-based caches). WARN if KVM attempts to activate a cache with INVALID_GPA, purely so that new caches need to at least consider what to do with a "bad" GPA, as all existing usage of kvm_gpc_activate() guarantees gpa != INVALID_GPA. I.e. removing the WARN in the future is completely reasonable if doing so would yield cleaner/better code overall. Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org> Link: https://lore.kernel.org/r/20240320001542.3203871-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
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Sean Christopherson
|
5c9ca4ed89 |
KVM: Check validity of offset+length of gfn_to_pfn_cache prior to activation
When activating a gfn_to_pfn_cache, verify that the offset+length is sane
and usable before marking the cache active. Letting __kvm_gpc_refresh()
detect the problem results in a cache being marked active without setting
the GPA (or any other fields), which in turn results in KVM trying to
refresh a cache with INVALID_GPA.
Attempting to refresh a cache with INVALID_GPA isn't functionally
problematic, but it runs afoul of the sanity check that exactly one of
GPA or userspace HVA is valid, i.e. that a cache is either GPA-based or
HVA-based.
Reported-by: syzbot+106a4f72b0474e1d1b33@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/0000000000005fa5cc0613f1cebd@google.com
Fixes:
|
||
|
Sean Christopherson
|
18f06e9769 |
KVM: Add helpers to consolidate gfn_to_pfn_cache's page split check
Add a helper to check that the incoming length for a gfn_to_pfn_cache is valid with respect to the cache's GPA and/or HVA. To avoid activating a cache with a bogus GPA, a future fix will fork the page split check in the inner refresh path into activate() and the public rerfresh() APIs, at which point KVM will check the length in three separate places. Deliberately keep the "page offset" logic open coded, as the only other path that consumes the offset, __kvm_gpc_refresh(), already needs to differentiate between GPA-based and HVA-based caches, and it's not obvious that using a helper is a net positive in overall code readability. Note, for GPA-based caches, this has a subtle side effect of using the GPA instead of the resolved HVA in the check() path, but that should be a nop as the HVA offset is derived from the GPA, i.e. the two offsets are identical, barring a KVM bug. Reviewed-by: Paul Durrant <paul@xen.org> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20240320001542.3203871-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Paolo Bonzini
|
e9a2bba476 |
KVM Xen and pfncache changes for 6.9:
- Rip out the half-baked support for using gfn_to_pfn caches to manage pages
that are "mapped" into guests via physical addresses.
- Add support for using gfn_to_pfn caches with only a host virtual address,
i.e. to bypass the "gfn" stage of the cache. The primary use case is
overlay pages, where the guest may change the gfn used to reference the
overlay page, but the backing hva+pfn remains the same.
- Add an ioctl() to allow mapping Xen's shared_info page using an hva instead
of a gpa, so that userspace doesn't need to reconfigure and invalidate the
cache/mapping if the guest changes the gpa (but userspace keeps the resolved
hva the same).
- When possible, use a single host TSC value when computing the deadline for
Xen timers in order to improve the accuracy of the timer emulation.
- Inject pending upcall events when the vCPU software-enables its APIC to fix
a bug where an upcall can be lost (and to follow Xen's behavior).
- Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen
events fails, e.g. if the guest has aliased xAPIC IDs.
- Extend gfn_to_pfn_cache's mutex to cover (de)activation (in addition to
refresh), and drop a now-redundant acquisition of xen_lock (that was
protecting the shared_info cache) to fix a deadlock due to recursively
acquiring xen_lock.
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Merge tag 'kvm-x86-xen-6.9' of https://github.com/kvm-x86/linux into HEAD
KVM Xen and pfncache changes for 6.9:
- Rip out the half-baked support for using gfn_to_pfn caches to manage pages
that are "mapped" into guests via physical addresses.
- Add support for using gfn_to_pfn caches with only a host virtual address,
i.e. to bypass the "gfn" stage of the cache. The primary use case is
overlay pages, where the guest may change the gfn used to reference the
overlay page, but the backing hva+pfn remains the same.
- Add an ioctl() to allow mapping Xen's shared_info page using an hva instead
of a gpa, so that userspace doesn't need to reconfigure and invalidate the
cache/mapping if the guest changes the gpa (but userspace keeps the resolved
hva the same).
- When possible, use a single host TSC value when computing the deadline for
Xen timers in order to improve the accuracy of the timer emulation.
- Inject pending upcall events when the vCPU software-enables its APIC to fix
a bug where an upcall can be lost (and to follow Xen's behavior).
- Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen
events fails, e.g. if the guest has aliased xAPIC IDs.
- Extend gfn_to_pfn_cache's mutex to cover (de)activation (in addition to
refresh), and drop a now-redundant acquisition of xen_lock (that was
protecting the shared_info cache) to fix a deadlock due to recursively
acquiring xen_lock.
|
||
|
Paolo Bonzini
|
c9cd0beae9 |
KVM x86 misc changes for 6.9:
- Explicitly initialize a variety of on-stack variables in the emulator that
triggered KMSAN false positives (though in fairness in KMSAN, it's comically
difficult to see that the uninitialized memory is never truly consumed).
- Fix the deubgregs ABI for 32-bit KVM, and clean up code related to reading
DR6 and DR7.
- Rework the "force immediate exit" code so that vendor code ultimately
decides how and when to force the exit. This allows VMX to further optimize
handling preemption timer exits, and allows SVM to avoid sending a duplicate
IPI (SVM also has a need to force an exit).
- Fix a long-standing bug where kvm_has_noapic_vcpu could be left elevated if
vCPU creation ultimately failed, and add WARN to guard against similar bugs.
- Provide a dedicated arch hook for checking if a different vCPU was in-kernel
(for directed yield), and simplify the logic for checking if the currently
loaded vCPU is in-kernel.
- Misc cleanups and fixes.
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Merge tag 'kvm-x86-misc-6.9' of https://github.com/kvm-x86/linux into HEAD
KVM x86 misc changes for 6.9:
- Explicitly initialize a variety of on-stack variables in the emulator that
triggered KMSAN false positives (though in fairness in KMSAN, it's comically
difficult to see that the uninitialized memory is never truly consumed).
- Fix the deubgregs ABI for 32-bit KVM, and clean up code related to reading
DR6 and DR7.
- Rework the "force immediate exit" code so that vendor code ultimately
decides how and when to force the exit. This allows VMX to further optimize
handling preemption timer exits, and allows SVM to avoid sending a duplicate
IPI (SVM also has a need to force an exit).
- Fix a long-standing bug where kvm_has_noapic_vcpu could be left elevated if
vCPU creation ultimately failed, and add WARN to guard against similar bugs.
- Provide a dedicated arch hook for checking if a different vCPU was in-kernel
(for directed yield), and simplify the logic for checking if the currently
loaded vCPU is in-kernel.
- Misc cleanups and fixes.
|
||
|
Paolo Bonzini
|
507e72f899 |
KVM common MMU changes for 6.9:
- Harden KVM against underflowing the active mmu_notifier invalidation
count, so that "bad" invalidations (usually due to bugs elsehwere in the
kernel) are detected earlier and are less likely to hang the kernel.
- Fix a benign bug in __kvm_mmu_topup_memory_cache() where the object size
and number of objects parameters to kvmalloc_array() were swapped.
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Merge tag 'kvm-x86-generic-6.9' of https://github.com/kvm-x86/linux into HEAD
KVM common MMU changes for 6.9:
- Harden KVM against underflowing the active mmu_notifier invalidation
count, so that "bad" invalidations (usually due to bugs elsehwere in the
kernel) are detected earlier and are less likely to hang the kernel.
- Fix a benign bug in __kvm_mmu_topup_memory_cache() where the object size
and number of objects parameters to kvmalloc_array() were swapped.
|
||
|
Paolo Bonzini
|
a81d95ae8c |
KVM async page fault changes for 6.9:
- Always flush the async page fault workqueue when a work item is being
removed, especially during vCPU destruction, to ensure that there are no
workers running in KVM code when all references to KVM-the-module are gone,
i.e. to prevent a use-after-free if kvm.ko is unloaded.
- Grab a reference to the VM's mm_struct in the async #PF worker itself instead
of gifting the worker a reference, e.g. so that there's no need to remember
to *conditionally* clean up after the worker.
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Merge tag 'kvm-x86-asyncpf-6.9' of https://github.com/kvm-x86/linux into HEAD
KVM async page fault changes for 6.9:
- Always flush the async page fault workqueue when a work item is being
removed, especially during vCPU destruction, to ensure that there are no
workers running in KVM code when all references to KVM-the-module are gone,
i.e. to prevent a use-after-free if kvm.ko is unloaded.
- Grab a reference to the VM's mm_struct in the async #PF worker itself instead
of gifting the worker a reference, e.g. so that there's no need to remember
to *conditionally* clean up after the worker.
|
||
|
Paolo Bonzini
|
961e2bfcf3 |
KVM/arm64 updates for 6.9
- Infrastructure for building KVM's trap configuration based on the
architectural features (or lack thereof) advertised in the VM's ID
registers
- Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to
x86's WC) at stage-2, improving the performance of interacting with
assigned devices that can tolerate it
- Conversion of KVM's representation of LPIs to an xarray, utilized to
address serialization some of the serialization on the LPI injection
path
- Support for _architectural_ VHE-only systems, advertised through the
absence of FEAT_E2H0 in the CPU's ID register
- Miscellaneous cleanups, fixes, and spelling corrections to KVM and
selftests
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Merge tag 'kvmarm-6.9' of https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 updates for 6.9
- Infrastructure for building KVM's trap configuration based on the
architectural features (or lack thereof) advertised in the VM's ID
registers
- Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to
x86's WC) at stage-2, improving the performance of interacting with
assigned devices that can tolerate it
- Conversion of KVM's representation of LPIs to an xarray, utilized to
address serialization some of the serialization on the LPI injection
path
- Support for _architectural_ VHE-only systems, advertised through the
absence of FEAT_E2H0 in the CPU's ID register
- Miscellaneous cleanups, fixes, and spelling corrections to KVM and
selftests
|
||
|
Paolo Bonzini
|
7d8942d8e7 |
KVM GUEST_MEMFD fixes for 6.8:
- Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY to
avoid creating ABI that KVM can't sanely support.
- Update documentation for KVM_SW_PROTECTED_VM to make it abundantly
clear that such VMs are purely a development and testing vehicle, and
come with zero guarantees.
- Limit KVM_SW_PROTECTED_VM guests to the TDP MMU, as the long term plan
is to support confidential VMs with deterministic private memory (SNP
and TDX) only in the TDP MMU.
- Fix a bug in a GUEST_MEMFD negative test that resulted in false passes
when verifying that KVM_MEM_GUEST_MEMFD memslots can't be dirty logged.
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Merge tag 'kvm-x86-guest_memfd_fixes-6.8' of https://github.com/kvm-x86/linux into HEAD
KVM GUEST_MEMFD fixes for 6.8:
- Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY to
avoid creating ABI that KVM can't sanely support.
- Update documentation for KVM_SW_PROTECTED_VM to make it abundantly
clear that such VMs are purely a development and testing vehicle, and
come with zero guarantees.
- Limit KVM_SW_PROTECTED_VM guests to the TDP MMU, as the long term plan
is to support confidential VMs with deterministic private memory (SNP
and TDX) only in the TDP MMU.
- Fix a bug in a GUEST_MEMFD negative test that resulted in false passes
when verifying that KVM_MEM_GUEST_MEMFD memslots can't be dirty logged.
|
||
David Woodhouse
|
6addfcf271 |
KVM: pfncache: simplify locking and make more self-contained
The locking on the gfn_to_pfn_cache is... interesting. And awful.
There is a rwlock in ->lock which readers take to ensure protection
against concurrent changes. But __kvm_gpc_refresh() makes assumptions
that certain fields will not change even while it drops the write lock
and performs MM operations to revalidate the target PFN and kernel
mapping.
Commit
|
||
|
Oliver Upton
|
284851ee5c |
KVM: Get rid of return value from kvm_arch_create_vm_debugfs()
The general expectation with debugfs is that any initialization failure is nonfatal. Nevertheless, kvm_arch_create_vm_debugfs() allows implementations to return an error and kvm_create_vm_debugfs() allows that to fail VM creation. Change to a void return to discourage architectures from making debugfs failures fatal for the VM. Seems like everyone already had the right idea, as all implementations already return 0 unconditionally. Acked-by: Marc Zyngier <maz@kernel.org> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Link: https://lore.kernel.org/r/20240216155941.2029458-1-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev> |
||
|
Sean Christopherson
|
e563592224 |
KVM: Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY
Disallow creating read-only memslots that support GUEST_MEMFD, as
GUEST_MEMFD is fundamentally incompatible with KVM's semantics for
read-only memslots. Read-only memslots allow the userspace VMM to emulate
option ROMs by filling the backing memory with readable, executable code
and data, while triggering emulated MMIO on writes. GUEST_MEMFD doesn't
currently support writes from userspace and KVM doesn't support emulated
MMIO on private accesses, i.e. the guest can only ever read zeros, and
writes will always be treated as errors.
Cc: Fuad Tabba <tabba@google.com>
Cc: Michael Roth <michael.roth@amd.com>
Cc: Isaku Yamahata <isaku.yamahata@gmail.com>
Cc: Yu Zhang <yu.c.zhang@linux.intel.com>
Cc: Chao Peng <chao.p.peng@linux.intel.com>
Fixes:
|
||
Arnd Bergmann
|
ea3689d9df |
KVM: fix kvm_mmu_memory_cache allocation warning
gcc-14 notices that the arguments to kvmalloc_array() are mixed up:
arch/x86/kvm/../../../virt/kvm/kvm_main.c: In function '__kvm_mmu_topup_memory_cache':
arch/x86/kvm/../../../virt/kvm/kvm_main.c:424:53: error: 'kvmalloc_array' sizes specified with 'sizeof' in the earlier argument and not in the later argument [-Werror=calloc-transposed-args]
424 | mc->objects = kvmalloc_array(sizeof(void *), capacity, gfp);
| ^~~~
arch/x86/kvm/../../../virt/kvm/kvm_main.c:424:53: note: earlier argument should specify number of elements, later size of each element
The code still works correctly, but the incorrect order prevents the compiler
from properly tracking the object sizes.
Fixes:
|
||
|
Sean Christopherson
|
dafc17dd52 |
KVM: Add a comment explaining the directed yield pending interrupt logic
Add a comment to explain why KVM treats vCPUs with pending interrupts as in-kernel when a vCPU wants to yield to a vCPU that was preempted while running in kernel mode. Link: https://lore.kernel.org/r/20240110003938.490206-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Sean Christopherson
|
77bcd9e623 |
KVM: Add dedicated arch hook for querying if vCPU was preempted in-kernel
Plumb in a dedicated hook for querying whether or not a vCPU was preempted in-kernel. Unlike literally every other architecture, x86's VMX can check if a vCPU is in kernel context if and only if the vCPU is loaded on the current pCPU. x86's kvm_arch_vcpu_in_kernel() works around the limitation by querying kvm_get_running_vcpu() and redirecting to vcpu->arch.preempted_in_kernel as needed. But that's unnecessary, confusing, and fragile, e.g. x86 has had at least one bug where KVM incorrectly used a stale preempted_in_kernel. No functional change intended. Reviewed-by: Yuan Yao <yuan.yao@intel.com> Link: https://lore.kernel.org/r/20240110003938.490206-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
Paul Durrant
|
9fa336e343 |
KVM: pfncache: check the need for invalidation under read lock first
When processing mmu_notifier invalidations for gpc caches, pre-check for overlap with the invalidation event while holding gpc->lock for read, and only take gpc->lock for write if the cache needs to be invalidated. Doing a pre-check without taking gpc->lock for write avoids unnecessarily contending the lock for unrelated invalidations, which is very beneficial for caches that are heavily used (but rarely subjected to mmu_notifier invalidations). Signed-off-by: Paul Durrant <pdurrant@amazon.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20240215152916.1158-20-paul@xen.org Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Paul Durrant
|
721f5b0dda |
KVM: pfncache: allow a cache to be activated with a fixed (userspace) HVA
Some pfncache pages may actually be overlays on guest memory that have a fixed HVA within the VMM. It's pointless to invalidate such cached mappings if the overlay is moved so allow a cache to be activated directly with the HVA to cater for such cases. A subsequent patch will make use of this facility. Signed-off-by: Paul Durrant <pdurrant@amazon.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20240215152916.1158-10-paul@xen.org Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Paul Durrant
|
406c10962a |
KVM: pfncache: include page offset in uhva and use it consistently
Currently the pfncache page offset is sometimes determined using the gpa and sometimes the khva, whilst the uhva is always page-aligned. After a subsequent patch is applied the gpa will not always be valid so adjust the code to include the page offset in the uhva and use it consistently as the source of truth. Also, where a page-aligned address is required, use PAGE_ALIGN_DOWN() for clarity. No functional change intended. Signed-off-by: Paul Durrant <pdurrant@amazon.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20240215152916.1158-8-paul@xen.org Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Paul Durrant
|
53e63e953e |
KVM: pfncache: stop open-coding offset_in_page()
Some code in pfncache uses offset_in_page() but in other places it is open- coded. Use offset_in_page() consistently everywhere. Signed-off-by: Paul Durrant <pdurrant@amazon.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20240215152916.1158-7-paul@xen.org Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Paul Durrant
|
a4bff3df51 |
KVM: pfncache: remove KVM_GUEST_USES_PFN usage
As noted in [1] the KVM_GUEST_USES_PFN usage flag is never set by any callers of kvm_gpc_init(), and for good reason: the implementation is incomplete/broken. And it's not clear that there will ever be a user of KVM_GUEST_USES_PFN, as coordinating vCPUs with mmu_notifier events is non-trivial. Remove KVM_GUEST_USES_PFN and all related code, e.g. dropping KVM_GUEST_USES_PFN also makes the 'vcpu' argument redundant, to avoid having to reason about broken code as __kvm_gpc_refresh() evolves. Moreover, all existing callers specify KVM_HOST_USES_PFN so the usage check in hva_to_pfn_retry() and hence the 'usage' argument to kvm_gpc_init() are also redundant. [1] https://lore.kernel.org/all/ZQiR8IpqOZrOpzHC@google.com Signed-off-by: Paul Durrant <pdurrant@amazon.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20240215152916.1158-6-paul@xen.org [sean: explicitly call out that guest usage is incomplete] Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Paul Durrant
|
41496fffc0 |
KVM: pfncache: remove unnecessary exports
There is no need for the existing kvm_gpc_XXX() functions to be exported. Clean up now before additional functions are added in subsequent patches. Signed-off-by: Paul Durrant <pdurrant@amazon.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20240215152916.1158-3-paul@xen.org Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Paul Durrant
|
f39b80e3ff |
KVM: pfncache: Add a map helper function
There is a pfncache unmap helper but mapping is open-coded. Arguably this is fine because mapping is done in only one place, hva_to_pfn_retry(), but adding the helper does make that function more readable. No functional change intended. Signed-off-by: Paul Durrant <pdurrant@amazon.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20240215152916.1158-2-paul@xen.org Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Paolo Bonzini
|
687d8f4c3d |
Merge branch 'kvm-kconfig'
Cleanups to Kconfig definitions for KVM * replace HAVE_KVM with an architecture-dependent symbol, when CONFIG_KVM may or may not be available depending on CPU capabilities (MIPS) * replace HAVE_KVM with IS_ENABLED(CONFIG_KVM) for host-side code that is not part of the KVM module, so that it is completely compiled out * factor common "select" statements in common code instead of requiring each architecture to specify it |
||
|
Paolo Bonzini
|
f48212ee8e |
treewide: remove CONFIG_HAVE_KVM
It has no users anymore. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Paolo Bonzini
|
61df71ee99 |
kvm: move "select IRQ_BYPASS_MANAGER" to common code
CONFIG_IRQ_BYPASS_MANAGER is a dependency of the common code included by CONFIG_HAVE_KVM_IRQ_BYPASS. There is no advantage in adding the corresponding "select" directive to each architecture. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Paolo Bonzini
|
8886640dad |
kvm: replace __KVM_HAVE_READONLY_MEM with Kconfig symbol
KVM uses __KVM_HAVE_* symbols in the architecture-dependent uapi/asm/kvm.h to mask unused definitions in include/uapi/linux/kvm.h. __KVM_HAVE_READONLY_MEM however was nothing but a misguided attempt to define KVM_CAP_READONLY_MEM only on architectures where KVM_CHECK_EXTENSION(KVM_CAP_READONLY_MEM) could possibly return nonzero. This however does not make sense, and it prevented userspace from supporting this architecture-independent feature without recompilation. Therefore, these days __KVM_HAVE_READONLY_MEM does not mask anything and is only used in virt/kvm/kvm_main.c. Userspace does not need to test it and there should be no need for it to exist. Remove it and replace it with a Kconfig symbol within Linux source code. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Sean Christopherson
|
c2744ed223 |
KVM: Nullify async #PF worker's "apf" pointer as soon as it might be freed
Nullify the async #PF worker's local "apf" pointer immediately after the point where the structure can be freed by the vCPU. The existing comment is helpful, but easy to overlook as there is no associated code. Update the comment to clarify that it can be freed by as soon as the lock is dropped, as "after this point" isn't strictly accurate, nor does it help understand what prevents the structure from being freed earlier. Reviewed-by: Xu Yilun <yilun.xu@intel.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Link: https://lore.kernel.org/r/20240110011533.503302-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Sean Christopherson
|
8284765f03 |
KVM: Get reference to VM's address space in the async #PF worker
Get a reference to the target VM's address space in async_pf_execute() instead of gifting a reference from kvm_setup_async_pf(). Keeping the address space alive just to service an async #PF is counter-productive, i.e. if the process is exiting and all vCPUs are dead, then NOT doing get_user_pages_remote() and freeing the address space asap is desirable. Handling the mm reference entirely within async_pf_execute() also simplifies the async #PF flows as a whole, e.g. it's not immediately obvious when the worker task vs. the vCPU task is responsible for putting the gifted mm reference. Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Xu Yilun <yilun.xu@intel.com> Link: https://lore.kernel.org/r/20240110011533.503302-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Sean Christopherson
|
422eeb543a |
KVM: Put mm immediately after async #PF worker completes remote gup()
Put the async #PF worker's reference to the VM's address space as soon as the worker is done with the mm. This will allow deferring getting a reference to the worker itself without having to track whether or not getting a reference succeeded. Note, if the vCPU is still alive, there is no danger of the worker getting stuck with tearing down the host page tables, as userspace also holds a reference (obviously), i.e. there is no risk of delaying the page-present notification due to triggering the slow path in mmput(). Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Xu Yilun <yilun.xu@intel.com> Link: https://lore.kernel.org/r/20240110011533.503302-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Sean Christopherson
|
3d75b8aa5c |
KVM: Always flush async #PF workqueue when vCPU is being destroyed
Always flush the per-vCPU async #PF workqueue when a vCPU is clearing its completion queue, e.g. when a VM and all its vCPUs is being destroyed. KVM must ensure that none of its workqueue callbacks is running when the last reference to the KVM _module_ is put. Gifting a reference to the associated VM prevents the workqueue callback from dereferencing freed vCPU/VM memory, but does not prevent the KVM module from being unloaded before the callback completes. Drop the misguided VM refcount gifting, as calling kvm_put_kvm() from async_pf_execute() if kvm_put_kvm() flushes the async #PF workqueue will result in deadlock. async_pf_execute() can't return until kvm_put_kvm() finishes, and kvm_put_kvm() can't return until async_pf_execute() finishes: WARNING: CPU: 8 PID: 251 at virt/kvm/kvm_main.c:1435 kvm_put_kvm+0x2d/0x320 [kvm] Modules linked in: vhost_net vhost vhost_iotlb tap kvm_intel kvm irqbypass CPU: 8 PID: 251 Comm: kworker/8:1 Tainted: G W 6.6.0-rc1-e7af8d17224a-x86/gmem-vm #119 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Workqueue: events async_pf_execute [kvm] RIP: 0010:kvm_put_kvm+0x2d/0x320 [kvm] Call Trace: <TASK> async_pf_execute+0x198/0x260 [kvm] process_one_work+0x145/0x2d0 worker_thread+0x27e/0x3a0 kthread+0xba/0xe0 ret_from_fork+0x2d/0x50 ret_from_fork_asm+0x11/0x20 </TASK> ---[ end trace 0000000000000000 ]--- INFO: task kworker/8:1:251 blocked for more than 120 seconds. Tainted: G W 6.6.0-rc1-e7af8d17224a-x86/gmem-vm #119 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/8:1 state:D stack:0 pid:251 ppid:2 flags:0x00004000 Workqueue: events async_pf_execute [kvm] Call Trace: <TASK> __schedule+0x33f/0xa40 schedule+0x53/0xc0 schedule_timeout+0x12a/0x140 __wait_for_common+0x8d/0x1d0 __flush_work.isra.0+0x19f/0x2c0 kvm_clear_async_pf_completion_queue+0x129/0x190 [kvm] kvm_arch_destroy_vm+0x78/0x1b0 [kvm] kvm_put_kvm+0x1c1/0x320 [kvm] async_pf_execute+0x198/0x260 [kvm] process_one_work+0x145/0x2d0 worker_thread+0x27e/0x3a0 kthread+0xba/0xe0 ret_from_fork+0x2d/0x50 ret_from_fork_asm+0x11/0x20 </TASK> If kvm_clear_async_pf_completion_queue() actually flushes the workqueue, then there's no need to gift async_pf_execute() a reference because all invocations of async_pf_execute() will be forced to complete before the vCPU and its VM are destroyed/freed. And that in turn fixes the module unloading bug as __fput() won't do module_put() on the last vCPU reference until the vCPU has been freed, e.g. if closing the vCPU file also puts the last reference to the KVM module. Note that kvm_check_async_pf_completion() may also take the work item off the completion queue and so also needs to flush the work queue, as the work will not be seen by kvm_clear_async_pf_completion_queue(). Waiting on the workqueue could theoretically delay a vCPU due to waiting for the work to complete, but that's a very, very small chance, and likely a very small delay. kvm_arch_async_page_present_queued() unconditionally makes a new request, i.e. will effectively delay entering the guest, so the remaining work is really just: trace_kvm_async_pf_completed(addr, cr2_or_gpa); __kvm_vcpu_wake_up(vcpu); mmput(mm); and mmput() can't drop the last reference to the page tables if the vCPU is still alive, i.e. the vCPU won't get stuck tearing down page tables. Add a helper to do the flushing, specifically to deal with "wakeup all" work items, as they aren't actually work items, i.e. are never placed in a workqueue. Trying to flush a bogus workqueue entry rightly makes __flush_work() complain (kudos to whoever added that sanity check). Note, commit |
||
|
Sean Christopherson
|
d489ec9565 |
KVM: Harden against unpaired kvm_mmu_notifier_invalidate_range_end() calls
When handling the end of an mmu_notifier invalidation, WARN if mn_active_invalidate_count is already 0 do not decrement it further, i.e. avoid causing mn_active_invalidate_count to underflow/wrap. In the worst case scenario, effectively corrupting mn_active_invalidate_count could cause kvm_swap_active_memslots() to hang indefinitely. end() calls are *supposed* to be paired with start(), i.e. underflow can only happen if there is a bug elsewhere in the kernel, but due to lack of lockdep assertions in the mmu_notifier helpers, it's all too easy for a bug to go unnoticed for some time, e.g. see the recently introduced PAGEMAP_SCAN ioctl(). Ideally, mmu_notifiers would incorporate lockdep assertions, but users of mmu_notifiers aren't required to hold any one specific lock, i.e. adding the necessary annotations to make lockdep aware of all locks that are mutally exclusive with mm_take_all_locks() isn't trivial. Link: https://lore.kernel.org/all/000000000000f6d051060c6785bc@google.com Link: https://lore.kernel.org/r/20240110004239.491290-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Linus Torvalds
|
09d1c6a80f |
Generic:
- Use memdup_array_user() to harden against overflow.
- Unconditionally advertise KVM_CAP_DEVICE_CTRL for all architectures.
- Clean up Kconfigs that all KVM architectures were selecting
- New functionality around "guest_memfd", a new userspace API that
creates an anonymous file and returns a file descriptor that refers
to it. guest_memfd files are bound to their owning virtual machine,
cannot be mapped, read, or written by userspace, and cannot be resized.
guest_memfd files do however support PUNCH_HOLE, which can be used to
switch a memory area between guest_memfd and regular anonymous memory.
- New ioctl KVM_SET_MEMORY_ATTRIBUTES allowing userspace to specify
per-page attributes for a given page of guest memory; right now the
only attribute is whether the guest expects to access memory via
guest_memfd or not, which in Confidential SVMs backed by SEV-SNP,
TDX or ARM64 pKVM is checked by firmware or hypervisor that guarantees
confidentiality (AMD PSP, Intel TDX module, or EL2 in the case of pKVM).
x86:
- Support for "software-protected VMs" that can use the new guest_memfd
and page attributes infrastructure. This is mostly useful for testing,
since there is no pKVM-like infrastructure to provide a meaningfully
reduced TCB.
- Fix a relatively benign off-by-one error when splitting huge pages during
CLEAR_DIRTY_LOG.
- Fix a bug where KVM could incorrectly test-and-clear dirty bits in non-leaf
TDP MMU SPTEs if a racing thread replaces a huge SPTE with a non-huge SPTE.
- Use more generic lockdep assertions in paths that don't actually care
about whether the caller is a reader or a writer.
- let Xen guests opt out of having PV clock reported as "based on a stable TSC",
because some of them don't expect the "TSC stable" bit (added to the pvclock
ABI by KVM, but never set by Xen) to be set.
- Revert a bogus, made-up nested SVM consistency check for TLB_CONTROL.
- Advertise flush-by-ASID support for nSVM unconditionally, as KVM always
flushes on nested transitions, i.e. always satisfies flush requests. This
allows running bleeding edge versions of VMware Workstation on top of KVM.
- Sanity check that the CPU supports flush-by-ASID when enabling SEV support.
- On AMD machines with vNMI, always rely on hardware instead of intercepting
IRET in some cases to detect unmasking of NMIs
- Support for virtualizing Linear Address Masking (LAM)
- Fix a variety of vPMU bugs where KVM fail to stop/reset counters and other state
prior to refreshing the vPMU model.
- Fix a double-overflow PMU bug by tracking emulated counter events using a
dedicated field instead of snapshotting the "previous" counter. If the
hardware PMC count triggers overflow that is recognized in the same VM-Exit
that KVM manually bumps an event count, KVM would pend PMIs for both the
hardware-triggered overflow and for KVM-triggered overflow.
- Turn off KVM_WERROR by default for all configs so that it's not
inadvertantly enabled by non-KVM developers, which can be problematic for
subsystems that require no regressions for W=1 builds.
- Advertise all of the host-supported CPUID bits that enumerate IA32_SPEC_CTRL
"features".
- Don't force a masterclock update when a vCPU synchronizes to the current TSC
generation, as updating the masterclock can cause kvmclock's time to "jump"
unexpectedly, e.g. when userspace hotplugs a pre-created vCPU.
- Use RIP-relative address to read kvm_rebooting in the VM-Enter fault paths,
partly as a super minor optimization, but mostly to make KVM play nice with
position independent executable builds.
- Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on
CONFIG_HYPERV as a minor optimization, and to self-document the code.
- Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV "emulation"
at build time.
ARM64:
- LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB
base granule sizes. Branch shared with the arm64 tree.
- Large Fine-Grained Trap rework, bringing some sanity to the
feature, although there is more to come. This comes with
a prefix branch shared with the arm64 tree.
- Some additional Nested Virtualization groundwork, mostly
introducing the NV2 VNCR support and retargetting the NV
support to that version of the architecture.
- A small set of vgic fixes and associated cleanups.
Loongarch:
- Optimization for memslot hugepage checking
- Cleanup and fix some HW/SW timer issues
- Add LSX/LASX (128bit/256bit SIMD) support
RISC-V:
- KVM_GET_REG_LIST improvement for vector registers
- Generate ISA extension reg_list using macros in get-reg-list selftest
- Support for reporting steal time along with selftest
s390:
- Bugfixes
Selftests:
- Fix an annoying goof where the NX hugepage test prints out garbage
instead of the magic token needed to run the test.
- Fix build errors when a header is delete/moved due to a missing flag
in the Makefile.
- Detect if KVM bugged/killed a selftest's VM and print out a helpful
message instead of complaining that a random ioctl() failed.
- Annotate the guest printf/assert helpers with __printf(), and fix the
various bugs that were lurking due to lack of said annotation.
There are two non-KVM patches buried in the middle of guest_memfd support:
fs: Rename anon_inode_getfile_secure() and anon_inode_getfd_secure()
mm: Add AS_UNMOVABLE to mark mapping as completely unmovable
The first is small and mostly suggested-by Christian Brauner; the second
a bit less so but it was written by an mm person (Vlastimil Babka).
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
"Generic:
- Use memdup_array_user() to harden against overflow.
- Unconditionally advertise KVM_CAP_DEVICE_CTRL for all
architectures.
- Clean up Kconfigs that all KVM architectures were selecting
- New functionality around "guest_memfd", a new userspace API that
creates an anonymous file and returns a file descriptor that refers
to it. guest_memfd files are bound to their owning virtual machine,
cannot be mapped, read, or written by userspace, and cannot be
resized. guest_memfd files do however support PUNCH_HOLE, which can
be used to switch a memory area between guest_memfd and regular
anonymous memory.
- New ioctl KVM_SET_MEMORY_ATTRIBUTES allowing userspace to specify
per-page attributes for a given page of guest memory; right now the
only attribute is whether the guest expects to access memory via
guest_memfd or not, which in Confidential SVMs backed by SEV-SNP,
TDX or ARM64 pKVM is checked by firmware or hypervisor that
guarantees confidentiality (AMD PSP, Intel TDX module, or EL2 in
the case of pKVM).
x86:
- Support for "software-protected VMs" that can use the new
guest_memfd and page attributes infrastructure. This is mostly
useful for testing, since there is no pKVM-like infrastructure to
provide a meaningfully reduced TCB.
- Fix a relatively benign off-by-one error when splitting huge pages
during CLEAR_DIRTY_LOG.
- Fix a bug where KVM could incorrectly test-and-clear dirty bits in
non-leaf TDP MMU SPTEs if a racing thread replaces a huge SPTE with
a non-huge SPTE.
- Use more generic lockdep assertions in paths that don't actually
care about whether the caller is a reader or a writer.
- let Xen guests opt out of having PV clock reported as "based on a
stable TSC", because some of them don't expect the "TSC stable" bit
(added to the pvclock ABI by KVM, but never set by Xen) to be set.
- Revert a bogus, made-up nested SVM consistency check for
TLB_CONTROL.
- Advertise flush-by-ASID support for nSVM unconditionally, as KVM
always flushes on nested transitions, i.e. always satisfies flush
requests. This allows running bleeding edge versions of VMware
Workstation on top of KVM.
- Sanity check that the CPU supports flush-by-ASID when enabling SEV
support.
- On AMD machines with vNMI, always rely on hardware instead of
intercepting IRET in some cases to detect unmasking of NMIs
- Support for virtualizing Linear Address Masking (LAM)
- Fix a variety of vPMU bugs where KVM fail to stop/reset counters
and other state prior to refreshing the vPMU model.
- Fix a double-overflow PMU bug by tracking emulated counter events
using a dedicated field instead of snapshotting the "previous"
counter. If the hardware PMC count triggers overflow that is
recognized in the same VM-Exit that KVM manually bumps an event
count, KVM would pend PMIs for both the hardware-triggered overflow
and for KVM-triggered overflow.
- Turn off KVM_WERROR by default for all configs so that it's not
inadvertantly enabled by non-KVM developers, which can be
problematic for subsystems that require no regressions for W=1
builds.
- Advertise all of the host-supported CPUID bits that enumerate
IA32_SPEC_CTRL "features".
- Don't force a masterclock update when a vCPU synchronizes to the
current TSC generation, as updating the masterclock can cause
kvmclock's time to "jump" unexpectedly, e.g. when userspace
hotplugs a pre-created vCPU.
- Use RIP-relative address to read kvm_rebooting in the VM-Enter
fault paths, partly as a super minor optimization, but mostly to
make KVM play nice with position independent executable builds.
- Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on
CONFIG_HYPERV as a minor optimization, and to self-document the
code.
- Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV
"emulation" at build time.
ARM64:
- LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB base
granule sizes. Branch shared with the arm64 tree.
- Large Fine-Grained Trap rework, bringing some sanity to the
feature, although there is more to come. This comes with a prefix
branch shared with the arm64 tree.
- Some additional Nested Virtualization groundwork, mostly
introducing the NV2 VNCR support and retargetting the NV support to
that version of the architecture.
- A small set of vgic fixes and associated cleanups.
Loongarch:
- Optimization for memslot hugepage checking
- Cleanup and fix some HW/SW timer issues
- Add LSX/LASX (128bit/256bit SIMD) support
RISC-V:
- KVM_GET_REG_LIST improvement for vector registers
- Generate ISA extension reg_list using macros in get-reg-list
selftest
- Support for reporting steal time along with selftest
s390:
- Bugfixes
Selftests:
- Fix an annoying goof where the NX hugepage test prints out garbage
instead of the magic token needed to run the test.
- Fix build errors when a header is delete/moved due to a missing
flag in the Makefile.
- Detect if KVM bugged/killed a selftest's VM and print out a helpful
message instead of complaining that a random ioctl() failed.
- Annotate the guest printf/assert helpers with __printf(), and fix
the various bugs that were lurking due to lack of said annotation"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (185 commits)
x86/kvm: Do not try to disable kvmclock if it was not enabled
KVM: x86: add missing "depends on KVM"
KVM: fix direction of dependency on MMU notifiers
KVM: introduce CONFIG_KVM_COMMON
KVM: arm64: Add missing memory barriers when switching to pKVM's hyp pgd
KVM: arm64: vgic-its: Avoid potential UAF in LPI translation cache
RISC-V: KVM: selftests: Add get-reg-list test for STA registers
RISC-V: KVM: selftests: Add steal_time test support
RISC-V: KVM: selftests: Add guest_sbi_probe_extension
RISC-V: KVM: selftests: Move sbi_ecall to processor.c
RISC-V: KVM: Implement SBI STA extension
RISC-V: KVM: Add support for SBI STA registers
RISC-V: KVM: Add support for SBI extension registers
RISC-V: KVM: Add SBI STA info to vcpu_arch
RISC-V: KVM: Add steal-update vcpu request
RISC-V: KVM: Add SBI STA extension skeleton
RISC-V: paravirt: Implement steal-time support
RISC-V: Add SBI STA extension definitions
RISC-V: paravirt: Add skeleton for pv-time support
RISC-V: KVM: Fix indentation in kvm_riscv_vcpu_set_reg_csr()
...
|
||
|
Linus Torvalds
|
c604110e66 |
vfs-6.8.misc
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Merge tag 'vfs-6.8.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
"This contains the usual miscellaneous features, cleanups, and fixes
for vfs and individual fses.
Features:
- Add Jan Kara as VFS reviewer
- Show correct device and inode numbers in proc/<pid>/maps for vma
files on stacked filesystems. This is now easily doable thanks to
the backing file work from the last cycles. This comes with
selftests
Cleanups:
- Remove a redundant might_sleep() from wait_on_inode()
- Initialize pointer with NULL, not 0
- Clarify comment on access_override_creds()
- Rework and simplify eventfd_signal() and eventfd_signal_mask()
helpers
- Process aio completions in batches to avoid needless wakeups
- Completely decouple struct mnt_idmap from namespaces. We now only
keep the actual idmapping around and don't stash references to
namespaces
- Reformat maintainer entries to indicate that a given subsystem
belongs to fs/
- Simplify fput() for files that were never opened
- Get rid of various pointless file helpers
- Rename various file helpers
- Rename struct file members after SLAB_TYPESAFE_BY_RCU switch from
last cycle
- Make relatime_need_update() return bool
- Use GFP_KERNEL instead of GFP_USER when allocating superblocks
- Replace deprecated ida_simple_*() calls with their current ida_*()
counterparts
Fixes:
- Fix comments on user namespace id mapping helpers. They aren't
kernel doc comments so they shouldn't be using /**
- s/Retuns/Returns/g in various places
- Add missing parameter documentation on can_move_mount_beneath()
- Rename i_mapping->private_data to i_mapping->i_private_data
- Fix a false-positive lockdep warning in pipe_write() for watch
queues
- Improve __fget_files_rcu() code generation to improve performance
- Only notify writer that pipe resizing has finished after setting
pipe->max_usage otherwise writers are never notified that the pipe
has been resized and hang
- Fix some kernel docs in hfsplus
- s/passs/pass/g in various places
- Fix kernel docs in ntfs
- Fix kcalloc() arguments order reported by gcc 14
- Fix uninitialized value in reiserfs"
* tag 'vfs-6.8.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (36 commits)
reiserfs: fix uninit-value in comp_keys
watch_queue: fix kcalloc() arguments order
ntfs: dir.c: fix kernel-doc function parameter warnings
fs: fix doc comment typo fs tree wide
selftests/overlayfs: verify device and inode numbers in /proc/pid/maps
fs/proc: show correct device and inode numbers in /proc/pid/maps
eventfd: Remove usage of the deprecated ida_simple_xx() API
fs: super: use GFP_KERNEL instead of GFP_USER for super block allocation
fs/hfsplus: wrapper.c: fix kernel-doc warnings
fs: add Jan Kara as reviewer
fs/inode: Make relatime_need_update return bool
pipe: wakeup wr_wait after setting max_usage
file: remove __receive_fd()
file: stop exposing receive_fd_user()
fs: replace f_rcuhead with f_task_work
file: remove pointless wrapper
file: s/close_fd_get_file()/file_close_fd()/g
Improve __fget_files_rcu() code generation (and thus __fget_light())
file: massage cleanup of files that failed to open
fs/pipe: Fix lockdep false-positive in watchqueue pipe_write()
...
|
||
|
Paolo Bonzini
|
fb872da8e7 |
Common KVM changes for 6.8:
- Use memdup_array_user() to harden against overflow. - Unconditionally advertise KVM_CAP_DEVICE_CTRL for all architectures. -----BEGIN PGP SIGNATURE----- iQJGBAABCgAwFiEEMHr+pfEFOIzK+KY1YJEiAU0MEvkFAmWW8F4SHHNlYW5qY0Bn b29nbGUuY29tAAoJEGCRIgFNDBL5urcP/Rex6Too26aHJXelUVHlFOGw3hfOnvbq Wr/P3kPqB/1Mncx3aiYTpEvUxFjVTvIkMB5dWba39Eq/G1BbOT2CAHCunlvKJrXy L83YgOl17QtZZJS1KmLTRCj1umfl4Z0c+GEIH+P1FOuOmllNXlLJ1+GWmolP6LLf u4DF2/tyVZf8JXXeJWYITHsU0YQQ0MhHgYL8/aMYJK8epNFpR3wKIqT3428ASxV3 Ru4WH7jpYkFF7PaKbvjKdepr+1wyVt4PXJDDpciCScz45/8eebgfylLJbMglpsR1 JSUTzd6KdCbekgzp51NnRdoIxP+MXgKA3dIuzXKyIDzm2Xq6tna87ve/aWDGw8JC nUMkP/vAuaKT+/QTOwskGAvK2GYDQD1UwVcFNLi12Iis50H0qPwcxsUionQuZgUC ykCmY4N31rSX4DhPg1WLiqsvC/EeDhfXprYrfSd4HQq08NgD45orRJw0Kov+shcS xijIlE1e3aVJMRrbfoSWyc4m79AcooxjYwojQC1Ayqsq0ZTTzzIpd6rqjmY+LbLL aP/wNz8hCfMhFekUV7dDk9rMdZY+bBnTiolyKAN66E6EnPYfl2EdrDEGnZOCPXF4 L/O/kMCXHE90cszzrmiR40yNHLkPelij8sK+ligE4JpqteQ7ia/knh8YAiPBxDw6 XcIfftXMm5XG =wpT4 -----END PGP SIGNATURE----- Merge tag 'kvm-x86-generic-6.8' of https://github.com/kvm-x86/linux into HEAD Common KVM changes for 6.8: - Use memdup_array_user() to harden against overflow. - Unconditionally advertise KVM_CAP_DEVICE_CTRL for all architectures. |
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Paolo Bonzini
|
3a373e027d |
KVM: fix direction of dependency on MMU notifiers
KVM_GENERIC_MEMORY_ATTRIBUTES requires the generic MMU notifier code, because it uses kvm_mmu_invalidate_begin/end. However, it would not work with a bespoke implementation of MMU notifiers that does not use KVM_GENERIC_MMU_NOTIFIER, because most likely it would not synchronize correctly on invalidation. So the right thing to do is to note the problematic configuration if the architecture does not select itself KVM_GENERIC_MMU_NOTIFIER; not to enable it blindly. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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Paolo Bonzini
|
caadf876bb |
KVM: introduce CONFIG_KVM_COMMON
CONFIG_HAVE_KVM is currently used by some architectures to either
enabled the KVM config proper, or to enable host-side code that is
not part of the KVM module. However, CONFIG_KVM's "select" statement
in virt/kvm/Kconfig corresponds to a third meaning, namely to
enable common Kconfigs required by all architectures that support
KVM.
These three meanings can be replaced respectively by an
architecture-specific Kconfig, by IS_ENABLED(CONFIG_KVM), or by
a new Kconfig symbol that is in turn selected by the
architecture-specific "config KVM".
Start by introducing such a new Kconfig symbol, CONFIG_KVM_COMMON.
Unlike CONFIG_HAVE_KVM, it is selected by CONFIG_KVM, not by
architecture code, and it brings in all dependencies of common
KVM code. In particular, INTERVAL_TREE was missing in loongarch
and riscv, so that is another thing that is fixed.
Fixes:
|
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Paolo Bonzini
|
9cc52627c7 |
KVM/riscv changes for 6.8 part #1
- KVM_GET_REG_LIST improvement for vector registers - Generate ISA extension reg_list using macros in get-reg-list selftest - Steal time account support along with selftest -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEZdn75s5e6LHDQ+f/rUjsVaLHLAcFAmWQ+cgACgkQrUjsVaLH LAckBA//R4X9L5ugfPdDunp3ntjZXmNtBS5pM2jD+UvaoFn2kOA1o5kOD5mXluuh 0imNjVuzlrX7XoAATQ4BoeoXg0whDbnv/8TE13KqSl1PfNziH2p5YD2DuHXPST3B V2VHrGACZ4wN074Whztl0oYI72obGnmpcsiglifkeCvRPerghHuDu40eUaWvCmgD DPwT+bjBgxkDZ4IheyytUrPql6reALh1Qo1vfj0FsJAgj+MAqQeD8n6rixSPnOdE 9XXa4jdu7ycDp675VX/DVEWsNBQGPrsRK/uCiMksO36td+wLCKpAkvX95mE0w/L8 qFJ+dN1c+1ZkjooHdVLfq2MjxaIRwmIowk7SeJbpvGIf/zG3r7eany7eXJT0+NjO 22j5FY2z1NqcSG6Fazx76Qp2vVBVbxHShP9h7d6VTZYS7XENjmV6IWHpTSuSF8+n puj8Nf5C7WuqbySirSgQndDuKawn9myqfXXEoAuSiZ+kVyYEl8QnXm2gAIcxRDHX x+NDPMv0DpMBRO9qa/tXeqgNue/XOTJwgbmXzAlCNff3U7hPIHJ/5aZiJ/Re5TeE DxiU9AmIsNN2Bh0csS/wQbdScIqkOdOiDYEwT1DXOJWpmhiyCW7vR8ltaIuMJ4vP DtlfuUlSe4aml957nAiqqyjQAY/7gqmpoaGwu+lmrOX1K7fdtF0= =FeiG -----END PGP SIGNATURE----- Merge tag 'kvm-riscv-6.8-1' of https://github.com/kvm-riscv/linux into HEAD KVM/riscv changes for 6.8 part #1 - KVM_GET_REG_LIST improvement for vector registers - Generate ISA extension reg_list using macros in get-reg-list selftest - Steal time account support along with selftest |
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Paolo Bonzini
|
136292522e |
LoongArch KVM changes for v6.8
1. Optimization for memslot hugepage checking. 2. Cleanup and fix some HW/SW timer issues. 3. Add LSX/LASX (128bit/256bit SIMD) support. -----BEGIN PGP SIGNATURE----- iQJKBAABCAA0FiEEzOlt8mkP+tbeiYy5AoYrw/LiJnoFAmWGu+0WHGNoZW5odWFj YWlAa2VybmVsLm9yZwAKCRAChivD8uImesO7D/wOdYP96R+mRzpLBeuTtFxU8e4A 3n2luxOeP8v1WYtQ9H8M01Wgly+9u6cJ2pgAlv79BQHfmCfC0aWQLmpnCZmk/mYW wtQ75ASA3Qg6zOBWEksCkA0LUdPDHfQuaaUXT7RYZ7QtHKSNkkhsw2nMCq6fgrXU RnZjGctjuxgYSqQtwzfYO2AjSBAfAq1MjSzCTULJ0KkE8o5Bg0KOoGj8ijC1U+ua QWBnqTNzeKmYmqAFfhXoiiFYcuBUq7DEk5RtwDU7SeqqJEV3a8AbbsrWfz+wMemG gri95uRxvnhpPZ+6/PrVjIezqexPJmQ9+tjY6mxh/bPRnS5ICFygjV3lt050JUK8 xIaJEFvl7g88RIz5mnTeM9tU4ibIsCLgA9zj33ps2H7QP5NazUm1dzk1YGAgqPdw m5hjwtTFQEujQM6cz1DLfhoi15VDNcYUonJIvGFZMhl7InitDpB3u9sI+AVGIVUG yKzBkqGB1L1vbJGnuWmspEqSUo7Z9iYzuVGbOnjc9LKQ/8OpLxj0brymYheA+CKG CIdULximQFVEHc2lbE+H+bW4hnrFP4sN9hlTng7KN7ommCIg+FltisM8Nt5NLWID 9ywLj4Qa0Qrc5vB3FJ8+ksuDe2nD83uVLj247R7B0wxQcYw4ocyW/YU+gayF4EjY 6azutwllW5ZB+I3hyw== =phol -----END PGP SIGNATURE----- Merge tag 'loongarch-kvm-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD LoongArch KVM changes for v6.8 1. Optimization for memslot hugepage checking. 2. Cleanup and fix some HW/SW timer issues. 3. Add LSX/LASX (128bit/256bit SIMD) support. |
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Paolo Bonzini
|
5c2b2176ea |
KVM/arm64 fixes for 6.7, part #2
- Ensure a vCPU's redistributor is unregistered from the MMIO bus
if vCPU creation fails
- Fix building KVM selftests for arm64 from the top-level Makefile
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Merge tag 'kvmarm-fixes-6.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master
KVM/arm64 fixes for 6.7, part #2
- Ensure a vCPU's redistributor is unregistered from the MMIO bus
if vCPU creation fails
- Fix building KVM selftests for arm64 from the top-level Makefile
|
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Marc Zyngier
|
b1a39a718d |
KVM: Convert comment into an assertion in kvm_io_bus_register_dev()
Instead of having a comment indicating the need to hold slots_lock when calling kvm_io_bus_register_dev(), make it explicit with a lockdep assertion. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20231207151201.3028710-6-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev> |
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Paolo Bonzini
|
8ed26ab8d5 |
KVM: clean up directives to compile out irqfds
Keep all #ifdef CONFIG_HAVE_KVM_IRQCHIP parts of eventfd.c together, and compile out the irqfds field of struct kvm if the symbol is not defined. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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Paolo Bonzini
|
a5d3df8ae1 |
KVM: remove deprecated UAPIs
The deprecated interfaces were removed 15 years ago. KVM's device assignment was deprecated in 4.2 and removed 6.5 years ago; the only interest might be in compiling ancient versions of QEMU, but QEMU has been using its own imported copy of the kernel headers since June 2011. So again we go into archaeology territory; just remove the cruft. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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Paolo Bonzini
|
c5b31cc237 |
KVM: remove CONFIG_HAVE_KVM_IRQFD
All platforms with a kernel irqchip have support for irqfd. Unify the two configuration items so that userspace can expect to use irqfd to inject interrupts into the irqchip. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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Paolo Bonzini
|
8132d887a7 |
KVM: remove CONFIG_HAVE_KVM_EVENTFD
virt/kvm/eventfd.c is compiled unconditionally, meaning that the ioeventfds member of struct kvm is accessed unconditionally. CONFIG_HAVE_KVM_EVENTFD therefore must be defined for KVM common code to compile successfully, remove it. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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Paolo Bonzini
|
80583d0cfd |
KVM: guest-memfd: fix unused-function warning
With migration disabled, one function becomes unused:
virt/kvm/guest_memfd.c:262:12: error: 'kvm_gmem_migrate_folio' defined but not used [-Werror=unused-function]
262 | static int kvm_gmem_migrate_folio(struct address_space *mapping,
| ^~~~~~~~~~~~~~~~~~~~~~
Remove the #ifdef around the reference so that fallback_migrate_folio()
is never used. The gmem implementation of the hook is trivial; since
the gmem mapping is unmovable, the pages should not be migrated anyway.
Fixes:
|
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|
Sean Christopherson
|
ea61294bef |
Revert "KVM: Prevent module exit until all VMs are freed"
Revert KVM's misguided attempt to "fix" a use-after-module-unload bug that was actually due to failure to flush a workqueue, not a lack of module refcounting. Pinning the KVM module until kvm_vm_destroy() doesn't prevent use-after-free due to the module being unloaded, as userspace can invoke delete_module() the instant the last reference to KVM is put, i.e. can cause all KVM code to be unmapped while KVM is actively executing said code. Generally speaking, the many instances of module_put(THIS_MODULE) notwithstanding, outside of a few special paths, a module can never safely put the last reference to itself without creating deadlock, i.e. something external to the module *must* put the last reference. In other words, having VMs grab a reference to the KVM module is futile, pointless, and as evidenced by the now-reverted commit |
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|
Sean Christopherson
|
087e15206d |
KVM: Set file_operations.owner appropriately for all such structures
Set .owner for all KVM-owned filed types so that the KVM module is pinned until any files with callbacks back into KVM are completely freed. Using "struct kvm" as a proxy for the module, i.e. keeping KVM-the-module alive while there are active VMs, doesn't provide full protection. Userspace can invoke delete_module() the instant the last reference to KVM is put. If KVM itself puts the last reference, e.g. via kvm_destroy_vm(), then it's possible for KVM to be preempted and deleted/unloaded before KVM fully exits, e.g. when the task running kvm_destroy_vm() is scheduled back in, it will jump to a code page that is no longer mapped. Note, file types that can call into sub-module code, e.g. kvm-intel.ko or kvm-amd.ko on x86, must use the module pointer passed to kvm_init(), not THIS_MODULE (which points at kvm.ko). KVM assumes that if /dev/kvm is reachable, e.g. VMs are active, then the vendor module is loaded. To reduce the probability of forgetting to set .owner entirely, use THIS_MODULE for stats files where KVM does not call back into vendor code. This reverts commit |
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Philipp Stanner
|
1f829359c8 |
KVM: Harden copying of userspace-array against overflow
kvm_main.c utilizes vmemdup_user() and array_size() to copy a userspace array. Currently, this does not check for an overflow. Use the new wrapper vmemdup_array_user() to copy the array more safely. Note, KVM explicitly checks the number of entries before duplicating the array, i.e. adding the overflow check should be a glorified nop. Suggested-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Philipp Stanner <pstanner@redhat.com> Link: https://lore.kernel.org/r/20231102181526.43279-4-pstanner@redhat.com [sean: call out that KVM pre-checks the number of entries] Signed-off-by: Sean Christopherson <seanjc@google.com> |
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Wei Wang
|
63912245c1 |
KVM: move KVM_CAP_DEVICE_CTRL to the generic check
KVM_CAP_DEVICE_CTRL allows userspace to check if the kvm_device framework (e.g. KVM_CREATE_DEVICE) is supported by KVM. Move KVM_CAP_DEVICE_CTRL to the generic check for the two reasons: 1) it already supports arch agnostic usages (i.e. KVM_DEV_TYPE_VFIO). For example, userspace VFIO implementation may needs to create KVM_DEV_TYPE_VFIO on x86, riscv, or arm etc. It is simpler to have it checked at the generic code than at each arch's code. 2) KVM_CREATE_DEVICE has been added to the generic code. Link: https://lore.kernel.org/all/20221215115207.14784-1-wei.w.wang@intel.com Signed-off-by: Wei Wang <wei.w.wang@intel.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Acked-by: Anup Patel <anup@brainfault.org> (riscv) Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Link: https://lore.kernel.org/r/20230315101606.10636-1-wei.w.wang@intel.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
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Christian Brauner
|
3652117f85 |
eventfd: simplify eventfd_signal()
Ever since the eventfd type was introduced back in 2007 in commit
|
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Paolo Bonzini
|
6c370dc653 |
Merge branch 'kvm-guestmemfd' into HEAD
Introduce several new KVM uAPIs to ultimately create a guest-first memory
subsystem within KVM, a.k.a. guest_memfd. Guest-first memory allows KVM
to provide features, enhancements, and optimizations that are kludgly
or outright impossible to implement in a generic memory subsystem.
The core KVM ioctl() for guest_memfd is KVM_CREATE_GUEST_MEMFD, which
similar to the generic memfd_create(), creates an anonymous file and
returns a file descriptor that refers to it. Again like "regular"
memfd files, guest_memfd files live in RAM, have volatile storage,
and are automatically released when the last reference is dropped.
The key differences between memfd files (and every other memory subystem)
is that guest_memfd files are bound to their owning virtual machine,
cannot be mapped, read, or written by userspace, and cannot be resized.
guest_memfd files do however support PUNCH_HOLE, which can be used to
convert a guest memory area between the shared and guest-private states.
A second KVM ioctl(), KVM_SET_MEMORY_ATTRIBUTES, allows userspace to
specify attributes for a given page of guest memory. In the long term,
it will likely be extended to allow userspace to specify per-gfn RWX
protections, including allowing memory to be writable in the guest
without it also being writable in host userspace.
The immediate and driving use case for guest_memfd are Confidential
(CoCo) VMs, specifically AMD's SEV-SNP, Intel's TDX, and KVM's own pKVM.
For such use cases, being able to map memory into KVM guests without
requiring said memory to be mapped into the host is a hard requirement.
While SEV+ and TDX prevent untrusted software from reading guest private
data by encrypting guest memory, pKVM provides confidentiality and
integrity *without* relying on memory encryption. In addition, with
SEV-SNP and especially TDX, accessing guest private memory can be fatal
to the host, i.e. KVM must be prevent host userspace from accessing
guest memory irrespective of hardware behavior.
Long term, guest_memfd may be useful for use cases beyond CoCo VMs,
for example hardening userspace against unintentional accesses to guest
memory. As mentioned earlier, KVM's ABI uses userspace VMA protections to
define the allow guest protection (with an exception granted to mapping
guest memory executable), and similarly KVM currently requires the guest
mapping size to be a strict subset of the host userspace mapping size.
Decoupling the mappings sizes would allow userspace to precisely map
only what is needed and with the required permissions, without impacting
guest performance.
A guest-first memory subsystem also provides clearer line of sight to
things like a dedicated memory pool (for slice-of-hardware VMs) and
elimination of "struct page" (for offload setups where userspace _never_
needs to DMA from or into guest memory).
guest_memfd is the result of 3+ years of development and exploration;
taking on memory management responsibilities in KVM was not the first,
second, or even third choice for supporting CoCo VMs. But after many
failed attempts to avoid KVM-specific backing memory, and looking at
where things ended up, it is quite clear that of all approaches tried,
guest_memfd is the simplest, most robust, and most extensible, and the
right thing to do for KVM and the kernel at-large.
The "development cycle" for this version is going to be very short;
ideally, next week I will merge it as is in kvm/next, taking this through
the KVM tree for 6.8 immediately after the end of the merge window.
The series is still based on 6.6 (plus KVM changes for 6.7) so it
will require a small fixup for changes to get_file_rcu() introduced in
6.7 by commit
|
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Sean Christopherson
|
89ea60c2c7 |
KVM: x86: Add support for "protected VMs" that can utilize private memory
Add a new x86 VM type, KVM_X86_SW_PROTECTED_VM, to serve as a development and testing vehicle for Confidential (CoCo) VMs, and potentially to even become a "real" product in the distant future, e.g. a la pKVM. The private memory support in KVM x86 is aimed at AMD's SEV-SNP and Intel's TDX, but those technologies are extremely complex (understatement), difficult to debug, don't support running as nested guests, and require hardware that's isn't universally accessible. I.e. relying SEV-SNP or TDX for maintaining guest private memory isn't a realistic option. At the very least, KVM_X86_SW_PROTECTED_VM will enable a variety of selftests for guest_memfd and private memory support without requiring unique hardware. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20231027182217.3615211-24-seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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Sean Christopherson
|
eed52e434b |
KVM: Allow arch code to track number of memslot address spaces per VM
Let x86 track the number of address spaces on a per-VM basis so that KVM can disallow SMM memslots for confidential VMs. Confidentials VMs are fundamentally incompatible with emulating SMM, which as the name suggests requires being able to read and write guest memory and register state. Disallowing SMM will simplify support for guest private memory, as KVM will not need to worry about tracking memory attributes for multiple address spaces (SMM is the only "non-default" address space across all architectures). Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-23-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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Sean Christopherson
|
a7800aa80e |
KVM: Add KVM_CREATE_GUEST_MEMFD ioctl() for guest-specific backing memory
Introduce an ioctl(), KVM_CREATE_GUEST_MEMFD, to allow creating file-based memory that is tied to a specific KVM virtual machine and whose primary purpose is to serve guest memory. A guest-first memory subsystem allows for optimizations and enhancements that are kludgy or outright infeasible to implement/support in a generic memory subsystem. With guest_memfd, guest protections and mapping sizes are fully decoupled from host userspace mappings. E.g. KVM currently doesn't support mapping memory as writable in the guest without it also being writable in host userspace, as KVM's ABI uses VMA protections to define the allow guest protection. Userspace can fudge this by establishing two mappings, a writable mapping for the guest and readable one for itself, but that’s suboptimal on multiple fronts. Similarly, KVM currently requires the guest mapping size to be a strict subset of the host userspace mapping size, e.g. KVM doesn’t support creating a 1GiB guest mapping unless userspace also has a 1GiB guest mapping. Decoupling the mappings sizes would allow userspace to precisely map only what is needed without impacting guest performance, e.g. to harden against unintentional accesses to guest memory. Decoupling guest and userspace mappings may also allow for a cleaner alternative to high-granularity mappings for HugeTLB, which has reached a bit of an impasse and is unlikely to ever be merged. A guest-first memory subsystem also provides clearer line of sight to things like a dedicated memory pool (for slice-of-hardware VMs) and elimination of "struct page" (for offload setups where userspace _never_ needs to mmap() guest memory). More immediately, being able to map memory into KVM guests without mapping said memory into the host is critical for Confidential VMs (CoCo VMs), the initial use case for guest_memfd. While AMD's SEV and Intel's TDX prevent untrusted software from reading guest private data by encrypting guest memory with a key that isn't usable by the untrusted host, projects such as Protected KVM (pKVM) provide confidentiality and integrity *without* relying on memory encryption. And with SEV-SNP and TDX, accessing guest private memory can be fatal to the host, i.e. KVM must be prevent host userspace from accessing guest memory irrespective of hardware behavior. Attempt #1 to support CoCo VMs was to add a VMA flag to mark memory as being mappable only by KVM (or a similarly enlightened kernel subsystem). That approach was abandoned largely due to it needing to play games with PROT_NONE to prevent userspace from accessing guest memory. Attempt #2 to was to usurp PG_hwpoison to prevent the host from mapping guest private memory into userspace, but that approach failed to meet several requirements for software-based CoCo VMs, e.g. pKVM, as the kernel wouldn't easily be able to enforce a 1:1 page:guest association, let alone a 1:1 pfn:gfn mapping. And using PG_hwpoison does not work for memory that isn't backed by 'struct page', e.g. if devices gain support for exposing encrypted memory regions to guests. Attempt #3 was to extend the memfd() syscall and wrap shmem to provide dedicated file-based guest memory. That approach made it as far as v10 before feedback from Hugh Dickins and Christian Brauner (and others) led to it demise. Hugh's objection was that piggybacking shmem made no sense for KVM's use case as KVM didn't actually *want* the features provided by shmem. I.e. KVM was using memfd() and shmem to avoid having to manage memory directly, not because memfd() and shmem were the optimal solution, e.g. things like read/write/mmap in shmem were dead weight. Christian pointed out flaws with implementing a partial overlay (wrapping only _some_ of shmem), e.g. poking at inode_operations or super_operations would show shmem stuff, but address_space_operations and file_operations would show KVM's overlay. Paraphrashing heavily, Christian suggested KVM stop being lazy and create a proper API. Link: https://lore.kernel.org/all/20201020061859.18385-1-kirill.shutemov@linux.intel.com Link: https://lore.kernel.org/all/20210416154106.23721-1-kirill.shutemov@linux.intel.com Link: https://lore.kernel.org/all/20210824005248.200037-1-seanjc@google.com Link: https://lore.kernel.org/all/20211111141352.26311-1-chao.p.peng@linux.intel.com Link: https://lore.kernel.org/all/20221202061347.1070246-1-chao.p.peng@linux.intel.com Link: https://lore.kernel.org/all/ff5c5b97-acdf-9745-ebe5-c6609dd6322e@google.com Link: https://lore.kernel.org/all/20230418-anfallen-irdisch-6993a61be10b@brauner Link: https://lore.kernel.org/all/ZEM5Zq8oo+xnApW9@google.com Link: https://lore.kernel.org/linux-mm/20230306191944.GA15773@monkey Link: https://lore.kernel.org/linux-mm/ZII1p8ZHlHaQ3dDl@casper.infradead.org Cc: Fuad Tabba <tabba@google.com> Cc: Vishal Annapurve <vannapurve@google.com> Cc: Ackerley Tng <ackerleytng@google.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Maciej Szmigiero <mail@maciej.szmigiero.name> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Hildenbrand <david@redhat.com> Cc: Quentin Perret <qperret@google.com> Cc: Michael Roth <michael.roth@amd.com> Cc: Wang <wei.w.wang@intel.com> Cc: Liam Merwick <liam.merwick@oracle.com> Cc: Isaku Yamahata <isaku.yamahata@gmail.com> Co-developed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Co-developed-by: Yu Zhang <yu.c.zhang@linux.intel.com> Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com> Co-developed-by: Chao Peng <chao.p.peng@linux.intel.com> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> Co-developed-by: Ackerley Tng <ackerleytng@google.com> Signed-off-by: Ackerley Tng <ackerleytng@google.com> Co-developed-by: Isaku Yamahata <isaku.yamahata@intel.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Co-developed-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20231027182217.3615211-17-seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
Chao Peng
|
5a475554db |
KVM: Introduce per-page memory attributes
In confidential computing usages, whether a page is private or shared is
necessary information for KVM to perform operations like page fault
handling, page zapping etc. There are other potential use cases for
per-page memory attributes, e.g. to make memory read-only (or no-exec,
or exec-only, etc.) without having to modify memslots.
Introduce the KVM_SET_MEMORY_ATTRIBUTES ioctl, advertised by
KVM_CAP_MEMORY_ATTRIBUTES, to allow userspace to set the per-page memory
attributes to a guest memory range.
Use an xarray to store the per-page attributes internally, with a naive,
not fully optimized implementation, i.e. prioritize correctness over
performance for the initial implementation.
Use bit 3 for the PRIVATE attribute so that KVM can use bits 0-2 for RWX
attributes/protections in the future, e.g. to give userspace fine-grained
control over read, write, and execute protections for guest memory.
Provide arch hooks for handling attribute changes before and after common
code sets the new attributes, e.g. x86 will use the "pre" hook to zap all
relevant mappings, and the "post" hook to track whether or not hugepages
can be used to map the range.
To simplify the implementation wrap the entire sequence with
kvm_mmu_invalidate_{begin,end}() even though the operation isn't strictly
guaranteed to be an invalidation. For the initial use case, x86 *will*
always invalidate memory, and preventing arch code from creating new
mappings while the attributes are in flux makes it much easier to reason
about the correctness of consuming attributes.
It's possible that future usages may not require an invalidation, e.g.
if KVM ends up supporting RWX protections and userspace grants _more_
protections, but again opt for simplicity and punt optimizations to
if/when they are needed.
Suggested-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/all/Y2WB48kD0J4VGynX@google.com
Cc: Fuad Tabba <tabba@google.com>
Cc: Xu Yilun <yilun.xu@intel.com>
Cc: Mickaël Salaün <mic@digikod.net>
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20231027182217.3615211-14-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
||
|
Sean Christopherson
|
193bbfaacc |
KVM: Drop .on_unlock() mmu_notifier hook
Drop the .on_unlock() mmu_notifer hook now that it's no longer used for notifying arch code that memory has been reclaimed. Adding .on_unlock() and invoking it *after* dropping mmu_lock was a terrible idea, as doing so resulted in .on_lock() and .on_unlock() having divergent and asymmetric behavior, and set future developers up for failure, i.e. all but asked for bugs where KVM relied on using .on_unlock() to try to run a callback while holding mmu_lock. Opportunistically add a lockdep assertion in kvm_mmu_invalidate_end() to guard against future bugs of this nature. Reported-by: Isaku Yamahata <isaku.yamahata@intel.com> Link: https://lore.kernel.org/all/20230802203119.GB2021422@ls.amr.corp.intel.com Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-12-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Sean Christopherson
|
cec29eef0a |
KVM: Add a dedicated mmu_notifier flag for reclaiming freed memory
Handle AMD SEV's kvm_arch_guest_memory_reclaimed() hook by having __kvm_handle_hva_range() return whether or not an overlapping memslot was found, i.e. mmu_lock was acquired. Using the .on_unlock() hook works, but kvm_arch_guest_memory_reclaimed() needs to run after dropping mmu_lock, which makes .on_lock() and .on_unlock() asymmetrical. Use a small struct to return the tuple of the notifier-specific return, plus whether or not overlap was found. Because the iteration helpers are __always_inlined, practically speaking, the struct will never actually be returned from a function call (not to mention the size of the struct will be two bytes in practice). Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-11-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Sean Christopherson
|
bb58b90b1a |
KVM: Introduce KVM_SET_USER_MEMORY_REGION2
Introduce a "version 2" of KVM_SET_USER_MEMORY_REGION so that additional information can be supplied without setting userspace up to fail. The padding in the new kvm_userspace_memory_region2 structure will be used to pass a file descriptor in addition to the userspace_addr, i.e. allow userspace to point at a file descriptor and map memory into a guest that is NOT mapped into host userspace. Alternatively, KVM could simply add "struct kvm_userspace_memory_region2" without a new ioctl(), but as Paolo pointed out, adding a new ioctl() makes detection of bad flags a bit more robust, e.g. if the new fd field is guarded only by a flag and not a new ioctl(), then a userspace bug (setting a "bad" flag) would generate out-of-bounds access instead of an -EINVAL error. Cc: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-9-seanjc@google.com> Acked-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Sean Christopherson
|
f128cf8cfb |
KVM: Convert KVM_ARCH_WANT_MMU_NOTIFIER to CONFIG_KVM_GENERIC_MMU_NOTIFIER
Convert KVM_ARCH_WANT_MMU_NOTIFIER into a Kconfig and select it where appropriate to effectively maintain existing behavior. Using a proper Kconfig will simplify building more functionality on top of KVM's mmu_notifier infrastructure. Add a forward declaration of kvm_gfn_range to kvm_types.h so that including arch/powerpc/include/asm/kvm_ppc.h's with CONFIG_KVM=n doesn't generate warnings due to kvm_gfn_range being undeclared. PPC defines hooks for PR vs. HV without guarding them via #ifdeffery, e.g. bool (*unmap_gfn_range)(struct kvm *kvm, struct kvm_gfn_range *range); bool (*age_gfn)(struct kvm *kvm, struct kvm_gfn_range *range); bool (*test_age_gfn)(struct kvm *kvm, struct kvm_gfn_range *range); bool (*set_spte_gfn)(struct kvm *kvm, struct kvm_gfn_range *range); Alternatively, PPC could forward declare kvm_gfn_range, but there's no good reason not to define it in common KVM. Acked-by: Anup Patel <anup@brainfault.org> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-8-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Sean Christopherson
|
d497a0fab8 |
KVM: WARN if there are dangling MMU invalidations at VM destruction
Add an assertion that there are no in-progress MMU invalidations when a VM is being destroyed, with the exception of the scenario where KVM unregisters its MMU notifier between an .invalidate_range_start() call and the corresponding .invalidate_range_end(). KVM can't detect unpaired calls from the mmu_notifier due to the above exception waiver, but the assertion can detect KVM bugs, e.g. such as the bug that *almost* escaped initial guest_memfd development. Link: https://lore.kernel.org/all/e397d30c-c6af-e68f-d18e-b4e3739c5389@linux.intel.com Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-5-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Chao Peng
|
8569992d64 |
KVM: Use gfn instead of hva for mmu_notifier_retry
Currently in mmu_notifier invalidate path, hva range is recorded and then checked against by mmu_invalidate_retry_hva() in the page fault handling path. However, for the soon-to-be-introduced private memory, a page fault may not have a hva associated, checking gfn(gpa) makes more sense. For existing hva based shared memory, gfn is expected to also work. The only downside is when aliasing multiple gfns to a single hva, the current algorithm of checking multiple ranges could result in a much larger range being rejected. Such aliasing should be uncommon, so the impact is expected small. Suggested-by: Sean Christopherson <seanjc@google.com> Cc: Xu Yilun <yilun.xu@intel.com> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> [sean: convert vmx_set_apic_access_page_addr() to gfn-based API] Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Xu Yilun <yilun.xu@linux.intel.com> Message-Id: <20231027182217.3615211-4-seanjc@google.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Sean Christopherson
|
c0db19232c |
KVM: Assert that mmu_invalidate_in_progress *never* goes negative
Move the assertion on the in-progress invalidation count from the primary MMU's notifier path to KVM's common notification path, i.e. assert that the count doesn't go negative even when the invalidation is coming from KVM itself. Opportunistically convert the assertion to a KVM_BUG_ON(), i.e. kill only the affected VM, not the entire kernel. A corrupted count is fatal to the VM, e.g. the non-zero (negative) count will cause mmu_invalidate_retry() to block any and all attempts to install new mappings. But it's far from guaranteed that an end() without a start() is fatal or even problematic to anything other than the target VM, e.g. the underlying bug could simply be a duplicate call to end(). And it's much more likely that a missed invalidation, i.e. a potential use-after-free, would manifest as no notification whatsoever, not an end() without a start(). Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-3-seanjc@google.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Sean Christopherson
|
e97b39c5c4 |
KVM: Tweak kvm_hva_range and hva_handler_t to allow reusing for gfn ranges
Rework and rename "struct kvm_hva_range" into "kvm_mmu_notifier_range" so that the structure can be used to handle notifications that operate on gfn context, i.e. that aren't tied to a host virtual address. Rename the handler typedef too (arguably it should always have been gfn_handler_t). Practically speaking, this is a nop for 64-bit kernels as the only meaningful change is to store start+end as u64s instead of unsigned longs. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-2-seanjc@google.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Linus Torvalds
|
0c02183427 |
ARM:
* Clean up vCPU targets, always returning generic v8 as the preferred target
* Trap forwarding infrastructure for nested virtualization (used for traps
that are taken from an L2 guest and are needed by the L1 hypervisor)
* FEAT_TLBIRANGE support to only invalidate specific ranges of addresses
when collapsing a table PTE to a block PTE. This avoids that the guest
refills the TLBs again for addresses that aren't covered by the table PTE.
* Fix vPMU issues related to handling of PMUver.
* Don't unnecessary align non-stack allocations in the EL2 VA space
* Drop HCR_VIRT_EXCP_MASK, which was never used...
* Don't use smp_processor_id() in kvm_arch_vcpu_load(),
but the cpu parameter instead
* Drop redundant call to kvm_set_pfn_accessed() in user_mem_abort()
* Remove prototypes without implementations
RISC-V:
* Zba, Zbs, Zicntr, Zicsr, Zifencei, and Zihpm support for guest
* Added ONE_REG interface for SATP mode
* Added ONE_REG interface to enable/disable multiple ISA extensions
* Improved error codes returned by ONE_REG interfaces
* Added KVM_GET_REG_LIST ioctl() implementation for KVM RISC-V
* Added get-reg-list selftest for KVM RISC-V
s390:
* PV crypto passthrough enablement (Tony, Steffen, Viktor, Janosch)
Allows a PV guest to use crypto cards. Card access is governed by
the firmware and once a crypto queue is "bound" to a PV VM every
other entity (PV or not) looses access until it is not bound
anymore. Enablement is done via flags when creating the PV VM.
* Guest debug fixes (Ilya)
x86:
* Clean up KVM's handling of Intel architectural events
* Intel bugfixes
* Add support for SEV-ES DebugSwap, allowing SEV-ES guests to use debug
registers and generate/handle #DBs
* Clean up LBR virtualization code
* Fix a bug where KVM fails to set the target pCPU during an IRTE update
* Fix fatal bugs in SEV-ES intrahost migration
* Fix a bug where the recent (architecturally correct) change to reinject
#BP and skip INT3 broke SEV guests (can't decode INT3 to skip it)
* Retry APIC map recalculation if a vCPU is added/enabled
* Overhaul emergency reboot code to bring SVM up to par with VMX, tie the
"emergency disabling" behavior to KVM actually being loaded, and move all of
the logic within KVM
* Fix user triggerable WARNs in SVM where KVM incorrectly assumes the TSC
ratio MSR cannot diverge from the default when TSC scaling is disabled
up related code
* Add a framework to allow "caching" feature flags so that KVM can check if
the guest can use a feature without needing to search guest CPUID
* Rip out the ancient MMU_DEBUG crud and replace the useful bits with
CONFIG_KVM_PROVE_MMU
* Fix KVM's handling of !visible guest roots to avoid premature triple fault
injection
* Overhaul KVM's page-track APIs, and KVMGT's usage, to reduce the API surface
that is needed by external users (currently only KVMGT), and fix a variety
of issues in the process
This last item had a silly one-character bug in the topic branch that
was sent to me. Because it caused pretty bad selftest failures in
some configurations, I decided to squash in the fix. So, while the
exact commit ids haven't been in linux-next, the code has (from the
kvm-x86 tree).
Generic:
* Wrap kvm_{gfn,hva}_range.pte in a union to allow mmu_notifier events to pass
action specific data without needing to constantly update the main handlers.
* Drop unused function declarations
Selftests:
* Add testcases to x86's sync_regs_test for detecting KVM TOCTOU bugs
* Add support for printf() in guest code and covert all guest asserts to use
printf-based reporting
* Clean up the PMU event filter test and add new testcases
* Include x86 selftests in the KVM x86 MAINTAINERS entry
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
"ARM:
- Clean up vCPU targets, always returning generic v8 as the preferred
target
- Trap forwarding infrastructure for nested virtualization (used for
traps that are taken from an L2 guest and are needed by the L1
hypervisor)
- FEAT_TLBIRANGE support to only invalidate specific ranges of
addresses when collapsing a table PTE to a block PTE. This avoids
that the guest refills the TLBs again for addresses that aren't
covered by the table PTE.
- Fix vPMU issues related to handling of PMUver.
- Don't unnecessary align non-stack allocations in the EL2 VA space
- Drop HCR_VIRT_EXCP_MASK, which was never used...
- Don't use smp_processor_id() in kvm_arch_vcpu_load(), but the cpu
parameter instead
- Drop redundant call to kvm_set_pfn_accessed() in user_mem_abort()
- Remove prototypes without implementations
RISC-V:
- Zba, Zbs, Zicntr, Zicsr, Zifencei, and Zihpm support for guest
- Added ONE_REG interface for SATP mode
- Added ONE_REG interface to enable/disable multiple ISA extensions
- Improved error codes returned by ONE_REG interfaces
- Added KVM_GET_REG_LIST ioctl() implementation for KVM RISC-V
- Added get-reg-list selftest for KVM RISC-V
s390:
- PV crypto passthrough enablement (Tony, Steffen, Viktor, Janosch)
Allows a PV guest to use crypto cards. Card access is governed by
the firmware and once a crypto queue is "bound" to a PV VM every
other entity (PV or not) looses access until it is not bound
anymore. Enablement is done via flags when creating the PV VM.
- Guest debug fixes (Ilya)
x86:
- Clean up KVM's handling of Intel architectural events
- Intel bugfixes
- Add support for SEV-ES DebugSwap, allowing SEV-ES guests to use
debug registers and generate/handle #DBs
- Clean up LBR virtualization code
- Fix a bug where KVM fails to set the target pCPU during an IRTE
update
- Fix fatal bugs in SEV-ES intrahost migration
- Fix a bug where the recent (architecturally correct) change to
reinject #BP and skip INT3 broke SEV guests (can't decode INT3 to
skip it)
- Retry APIC map recalculation if a vCPU is added/enabled
- Overhaul emergency reboot code to bring SVM up to par with VMX, tie
the "emergency disabling" behavior to KVM actually being loaded,
and move all of the logic within KVM
- Fix user triggerable WARNs in SVM where KVM incorrectly assumes the
TSC ratio MSR cannot diverge from the default when TSC scaling is
disabled up related code
- Add a framework to allow "caching" feature flags so that KVM can
check if the guest can use a feature without needing to search
guest CPUID
- Rip out the ancient MMU_DEBUG crud and replace the useful bits with
CONFIG_KVM_PROVE_MMU
- Fix KVM's handling of !visible guest roots to avoid premature
triple fault injection
- Overhaul KVM's page-track APIs, and KVMGT's usage, to reduce the
API surface that is needed by external users (currently only
KVMGT), and fix a variety of issues in the process
Generic:
- Wrap kvm_{gfn,hva}_range.pte in a union to allow mmu_notifier
events to pass action specific data without needing to constantly
update the main handlers.
- Drop unused function declarations
Selftests:
- Add testcases to x86's sync_regs_test for detecting KVM TOCTOU bugs
- Add support for printf() in guest code and covert all guest asserts
to use printf-based reporting
- Clean up the PMU event filter test and add new testcases
- Include x86 selftests in the KVM x86 MAINTAINERS entry"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (279 commits)
KVM: x86/mmu: Include mmu.h in spte.h
KVM: x86/mmu: Use dummy root, backed by zero page, for !visible guest roots
KVM: x86/mmu: Disallow guest from using !visible slots for page tables
KVM: x86/mmu: Harden TDP MMU iteration against root w/o shadow page
KVM: x86/mmu: Harden new PGD against roots without shadow pages
KVM: x86/mmu: Add helper to convert root hpa to shadow page
drm/i915/gvt: Drop final dependencies on KVM internal details
KVM: x86/mmu: Handle KVM bookkeeping in page-track APIs, not callers
KVM: x86/mmu: Drop @slot param from exported/external page-track APIs
KVM: x86/mmu: Bug the VM if write-tracking is used but not enabled
KVM: x86/mmu: Assert that correct locks are held for page write-tracking
KVM: x86/mmu: Rename page-track APIs to reflect the new reality
KVM: x86/mmu: Drop infrastructure for multiple page-track modes
KVM: x86/mmu: Use page-track notifiers iff there are external users
KVM: x86/mmu: Move KVM-only page-track declarations to internal header
KVM: x86: Remove the unused page-track hook track_flush_slot()
drm/i915/gvt: switch from ->track_flush_slot() to ->track_remove_region()
KVM: x86: Add a new page-track hook to handle memslot deletion
drm/i915/gvt: Don't bother removing write-protection on to-be-deleted slot
KVM: x86: Reject memslot MOVE operations if KVMGT is attached
...
|
||
|
Paolo Bonzini
|
0d15bf966d |
Common KVM changes for 6.6:
- Wrap kvm_{gfn,hva}_range.pte in a union to allow mmu_notifier events to pass
action specific data without needing to constantly update the main handlers.
- Drop unused function declarations
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Merge tag 'kvm-x86-generic-6.6' of https://github.com/kvm-x86/linux into HEAD
Common KVM changes for 6.6:
- Wrap kvm_{gfn,hva}_range.pte in a union to allow mmu_notifier events to pass
action specific data without needing to constantly update the main handlers.
- Drop unused function declarations
|
||
|
Paolo Bonzini
|
e0fb12c673 |
KVM/arm64 updates for Linux 6.6
- Add support for TLB range invalidation of Stage-2 page tables, avoiding unnecessary invalidations. Systems that do not implement range invalidation still rely on a full invalidation when dealing with large ranges. - Add infrastructure for forwarding traps taken from a L2 guest to the L1 guest, with L0 acting as the dispatcher, another baby step towards the full nested support. - Simplify the way we deal with the (long deprecated) 'CPU target', resulting in a much needed cleanup. - Fix another set of PMU bugs, both on the guest and host sides, as we seem to never have any shortage of those... - Relax the alignment requirements of EL2 VA allocations for non-stack allocations, as we were otherwise wasting a lot of that precious VA space. - The usual set of non-functional cleanups, although I note the lack of spelling fixes... -----BEGIN PGP SIGNATURE----- iQJDBAABCgAtFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAmTsXrUPHG1hekBrZXJu ZWwub3JnAAoJECPQ0LrRPXpDZpIQAJUM1rNEOJ8ExYRfoG1LaTfcOm5TD6D1IWlO uCUx4xLMBudw/55HusmUSdiomQ3Xg5UdRaU7vX5OYwPbdoWebjEUfgdP3jCA/TiW mZTMv3x9hOvp+EOS/UnS469cERvg1/KfwcdOQsWL0HsCFZnu2XmQHWPD++vovLNp F1892ij875mC6C6mOR60H2nyjIiCuqWh/8eKBkp65CARCbFDYxWhqBnmcmTvoquh E87pQDPdtgXc0KlOWCABh5bYOu1WGVEXE5f3ixtdY9cQakkSI3NkFKw27/mIWS4q TCsagByNnPFDXTglb1dJopNdluLMFi1iXhRJX78R/PYaHxf4uFafWcQk1U7eDdLg 1kPANggwYe4KNAQZUvRhH7lIPWHCH0r4c1qHV+FsiOZVoDOSKHo4RW1ZFtirJSNW LNJMdk+8xyae0S7z164EpZB/tpFttX4gl3YvUT/T+4gH8+CRFAaoAlK39CoGDPpk f+P2GE1Z5YupF16YjpZtBnan55KkU1b6eORl5zpnAtoaz5WGXqj1t4qo0Q6e9WB9 X4rdDVhH7vRUmhjmSP6PuEygb84hnITLdGpkH2BmWj/4uYuCN+p+U2B2o/QdMJoo cPxdflLOU/+1gfAFYPtHVjVKCqzhwbw3iLXQpO12gzRYqE13rUnAr7RuGDf5fBVC LW7Pv81o =DKhx -----END PGP SIGNATURE----- Merge tag 'kvmarm-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for Linux 6.6 - Add support for TLB range invalidation of Stage-2 page tables, avoiding unnecessary invalidations. Systems that do not implement range invalidation still rely on a full invalidation when dealing with large ranges. - Add infrastructure for forwarding traps taken from a L2 guest to the L1 guest, with L0 acting as the dispatcher, another baby step towards the full nested support. - Simplify the way we deal with the (long deprecated) 'CPU target', resulting in a much needed cleanup. - Fix another set of PMU bugs, both on the guest and host sides, as we seem to never have any shortage of those... - Relax the alignment requirements of EL2 VA allocations for non-stack allocations, as we were otherwise wasting a lot of that precious VA space. - The usual set of non-functional cleanups, although I note the lack of spelling fixes... |
||
|
Linus Torvalds
|
ec0e2dc810 |
VFIO updates for v6.6-rc1
- VFIO direct character device (cdev) interface support. This extracts
the vfio device fd from the container and group model, and is intended
to be the native uAPI for use with IOMMUFD. (Yi Liu)
- Enhancements to the PCI hot reset interface in support of cdev usage.
(Yi Liu)
- Fix a potential race between registering and unregistering vfio files
in the kvm-vfio interface and extend use of a lock to avoid extra
drop and acquires. (Dmitry Torokhov)
- A new vfio-pci variant driver for the AMD/Pensando Distributed Services
Card (PDS) Ethernet device, supporting live migration. (Brett Creeley)
- Cleanups to remove redundant owner setup in cdx and fsl bus drivers,
and simplify driver init/exit in fsl code. (Li Zetao)
- Fix uninitialized hole in data structure and pad capability structures
for alignment. (Stefan Hajnoczi)
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Merge tag 'vfio-v6.6-rc1' of https://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:
- VFIO direct character device (cdev) interface support. This extracts
the vfio device fd from the container and group model, and is
intended to be the native uAPI for use with IOMMUFD (Yi Liu)
- Enhancements to the PCI hot reset interface in support of cdev usage
(Yi Liu)
- Fix a potential race between registering and unregistering vfio files
in the kvm-vfio interface and extend use of a lock to avoid extra
drop and acquires (Dmitry Torokhov)
- A new vfio-pci variant driver for the AMD/Pensando Distributed
Services Card (PDS) Ethernet device, supporting live migration (Brett
Creeley)
- Cleanups to remove redundant owner setup in cdx and fsl bus drivers,
and simplify driver init/exit in fsl code (Li Zetao)
- Fix uninitialized hole in data structure and pad capability
structures for alignment (Stefan Hajnoczi)
* tag 'vfio-v6.6-rc1' of https://github.com/awilliam/linux-vfio: (53 commits)
vfio/pds: Send type for SUSPEND_STATUS command
vfio/pds: fix return value in pds_vfio_get_lm_file()
pds_core: Fix function header descriptions
vfio: align capability structures
vfio/type1: fix cap_migration information leak
vfio/fsl-mc: Use module_fsl_mc_driver macro to simplify the code
vfio/cdx: Remove redundant initialization owner in vfio_cdx_driver
vfio/pds: Add Kconfig and documentation
vfio/pds: Add support for firmware recovery
vfio/pds: Add support for dirty page tracking
vfio/pds: Add VFIO live migration support
vfio/pds: register with the pds_core PF
pds_core: Require callers of register/unregister to pass PF drvdata
vfio/pds: Initial support for pds VFIO driver
vfio: Commonize combine_ranges for use in other VFIO drivers
kvm/vfio: avoid bouncing the mutex when adding and deleting groups
kvm/vfio: ensure kvg instance stays around in kvm_vfio_group_add()
docs: vfio: Add vfio device cdev description
vfio: Compile vfio_group infrastructure optionally
vfio: Move the IOMMU_CAP_CACHE_COHERENCY check in __vfio_register_dev()
...
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||
|
David Hildenbrand
|
b1e1296d7c |
kvm: explicitly set FOLL_HONOR_NUMA_FAULT in hva_to_pfn_slow()
KVM is *the* case we know that really wants to honor NUMA hinting falls. As we want to stop setting FOLL_HONOR_NUMA_FAULT implicitly, set FOLL_HONOR_NUMA_FAULT whenever we might obtain pages on behalf of a VCPU to map them into a secondary MMU, and add a comment why. Do that unconditionally in hva_to_pfn_slow() when calling get_user_pages_unlocked(). kvmppc_book3s_instantiate_page(), hva_to_pfn_fast() and gfn_to_page_many_atomic() are similarly used to map pages into a secondary MMU. However, FOLL_WRITE and get_user_page_fast_only() always implicitly honor NUMA hinting faults -- as documented for FOLL_HONOR_NUMA_FAULT -- so we can limit this change to a single location for now. Don't set it in check_user_page_hwpoison(), where we really only want to check if the mapped page is HW-poisoned. We won't set it for other KVM users of get_user_pages()/pin_user_pages() * arch/powerpc/kvm/book3s_64_mmu_hv.c: not used to map pages into a secondary MMU. * arch/powerpc/kvm/e500_mmu.c: only used on shared TLB pages with userspace * arch/s390/kvm/*: s390x only supports a single NUMA node either way * arch/x86/kvm/svm/sev.c: not used to map pages into a secondary MMU. This is a preparation for making FOLL_HONOR_NUMA_FAULT no longer implicitly be set by get_user_pages() and friends. Link: https://lkml.kernel.org/r/20230803143208.383663-4-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: liubo <liubo254@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Xu <peterx@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
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Sean Christopherson
|
3e1efe2b67 |
KVM: Wrap kvm_{gfn,hva}_range.pte in a per-action union
Wrap kvm_{gfn,hva}_range.pte in a union so that future notifier events can
pass event specific information up and down the stack without needing to
constantly expand and churn the APIs. Lockless aging of SPTEs will pass
around a bitmap, and support for memory attributes will pass around the
new attributes for the range.
Add a "KVM_NO_ARG" placeholder to simplify handling events without an
argument (creating a dummy union variable is midly annoying).
Opportunstically drop explicit zero-initialization of the "pte" field, as
omitting the field (now a union) has the same effect.
Cc: Yu Zhao <yuzhao@google.com>
Link: https://lore.kernel.org/all/CAOUHufagkd2Jk3_HrVoFFptRXM=hX2CV8f+M-dka-hJU4bP8kw@mail.gmail.com
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Acked-by: Yu Zhao <yuzhao@google.com>
Link: https://lore.kernel.org/r/20230729004144.1054885-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
||
David Matlack
|
619b507244 |
KVM: Move kvm_arch_flush_remote_tlbs_memslot() to common code
Move kvm_arch_flush_remote_tlbs_memslot() to common code and drop "arch_" from the name. kvm_arch_flush_remote_tlbs_memslot() is just a range-based TLB invalidation where the range is defined by the memslot. Now that kvm_flush_remote_tlbs_range() can be called from common code we can just use that and drop a bunch of duplicate code from the arch directories. Note this adds a lockdep assertion for slots_lock being held when calling kvm_flush_remote_tlbs_memslot(), which was previously only asserted on x86. MIPS has calls to kvm_flush_remote_tlbs_memslot(), but they all hold the slots_lock, so the lockdep assertion continues to hold true. Also drop the CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT ifdef gating kvm_flush_remote_tlbs_memslot(), since it is no longer necessary. Signed-off-by: David Matlack <dmatlack@google.com> Signed-off-by: Raghavendra Rao Ananta <rananta@google.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Shaoqin Huang <shahuang@redhat.com> Acked-by: Anup Patel <anup@brainfault.org> Acked-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230811045127.3308641-7-rananta@google.com |
||
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David Matlack
|
d478899605 |
KVM: Allow range-based TLB invalidation from common code
Make kvm_flush_remote_tlbs_range() visible in common code and create a default implementation that just invalidates the whole TLB. This paves the way for several future features/cleanups: - Introduction of range-based TLBI on ARM. - Eliminating kvm_arch_flush_remote_tlbs_memslot() - Moving the KVM/x86 TDP MMU to common code. No functional change intended. Signed-off-by: David Matlack <dmatlack@google.com> Signed-off-by: Raghavendra Rao Ananta <rananta@google.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Shaoqin Huang <shahuang@redhat.com> Reviewed-by: Anup Patel <anup@brainfault.org> Acked-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230811045127.3308641-6-rananta@google.com |