When destroying a VM we return the LPID to the pool, however we never
zero the partition table entry. This is instead done when we reallocate
the LPID.
Zero the partition table entry on VM teardown before returning the LPID
to the pool. This means if we were running as a nested hypervisor the
real hypervisor could use this to determine when it can free resources.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When the 'regs' field was added to struct kvm_vcpu_arch, the code
was changed to use several of the fields inside regs (e.g., gpr, lr,
etc.) but not the ccr field, because the ccr field in struct pt_regs
is 64 bits on 64-bit platforms, but the cr field in kvm_vcpu_arch is
only 32 bits. This changes the code to use the regs.ccr field
instead of cr, and changes the assembly code on 64-bit platforms to
use 64-bit loads and stores instead of 32-bit ones.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds a file called 'radix' in the debugfs directory for the
guest, which when read gives all of the valid leaf PTEs in the
partition-scoped radix tree for a radix guest, in human-readable
format. It is analogous to the existing 'htab' file which dumps
the HPT entries for a HPT guest.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently the code for handling hypervisor instruction page faults
passes 0 for the flags indicating the type of fault, which is OK in
the usual case that the page is not mapped in the partition-scoped
page tables. However, there are other causes for hypervisor
instruction page faults, such as not being to update a reference
(R) or change (C) bit. The cause is indicated in bits in HSRR1,
including a bit which indicates that the fault is due to not being
able to write to a page (for example to update an R or C bit).
Not handling these other kinds of faults correctly can lead to a
loop of continual faults without forward progress in the guest.
In order to handle these faults better, this patch constructs a
"DSISR-like" value from the bits which DSISR and SRR1 (for a HISI)
have in common, and passes it to kvmppc_book3s_hv_page_fault() so
that it knows what caused the fault.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This creates an alternative guest entry/exit path which is used for
radix guests on POWER9 systems when we have indep_threads_mode=Y. In
these circumstances there is exactly one vcpu per vcore and there is
no coordination required between vcpus or vcores; the vcpu can enter
the guest without needing to synchronize with anything else.
The new fast path is implemented almost entirely in C in book3s_hv.c
and runs with the MMU on until the guest is entered. On guest exit
we use the existing path until the point where we are committed to
exiting the guest (as distinct from handling an interrupt in the
low-level code and returning to the guest) and we have pulled the
guest context from the XIVE. At that point we check a flag in the
stack frame to see whether we came in via the old path and the new
path; if we came in via the new path then we go back to C code to do
the rest of the process of saving the guest context and restoring the
host context.
The C code is split into separate functions for handling the
OS-accessible state and the hypervisor state, with the idea that the
latter can be replaced by a hypercall when we implement nested
virtualization.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
[mpe: Fix CONFIG_ALTIVEC=n build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently kvmppc_handle_exit_hv() is called with the vcore lock held
because it is called within a for_each_runnable_thread loop.
However, we already unlock the vcore within kvmppc_handle_exit_hv()
under certain circumstances, and this is safe because (a) any vcpus
that become runnable and are added to the runnable set by
kvmppc_run_vcpu() have their vcpu->arch.trap == 0 and can't actually
run in the guest (because the vcore state is VCORE_EXITING), and
(b) for_each_runnable_thread is safe against addition or removal
of vcpus from the runnable set.
Therefore, in order to simplify things for following patches, let's
drop the vcore lock in the for_each_runnable_thread loop, so
kvmppc_handle_exit_hv() gets called without the vcore lock held.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This is based on a patch by Suraj Jitindar Singh.
This moves the code in book3s_hv_rmhandlers.S that generates an
external, decrementer or privileged doorbell interrupt just before
entering the guest to C code in book3s_hv_builtin.c. This is to
make future maintenance and modification easier. The algorithm
expressed in the C code is almost identical to the previous
algorithm.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
- An implementation for the newly added hv_ops->flush() for the OPAL hvc
console driver backends, I forgot to apply this after merging the hvc driver
changes before the merge window.
- Enable all PCI bridges at boot on powernv, to avoid races when multiple
children of a bridge try to enable it simultaneously. This is a workaround
until the PCI core can be enhanced to fix the races.
- A fix to query PowerVM for the correct system topology at boot before
initialising sched domains, seen in some configurations to cause broken
scheduling etc.
- A fix for pte_access_permitted() on "nohash" platforms.
- Two commits to fix SIGBUS when using remap_pfn_range() seen on Power9 due to
a workaround when using the nest MMU (GPUs, accelerators).
- Another fix to the VFIO code used by KVM, the previous fix had some bugs
which caused guests to not start in some configurations.
- A handful of other minor fixes.
Thanks to:
Aneesh Kumar K.V, Benjamin Herrenschmidt, Christophe Leroy, Hari Bathini, Luke
Dashjr, Mahesh Salgaonkar, Nicholas Piggin, Paul Mackerras, Srikar Dronamraju.
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Merge tag 'powerpc-4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
- An implementation for the newly added hv_ops->flush() for the OPAL
hvc console driver backends, I forgot to apply this after merging the
hvc driver changes before the merge window.
- Enable all PCI bridges at boot on powernv, to avoid races when
multiple children of a bridge try to enable it simultaneously. This
is a workaround until the PCI core can be enhanced to fix the races.
- A fix to query PowerVM for the correct system topology at boot before
initialising sched domains, seen in some configurations to cause
broken scheduling etc.
- A fix for pte_access_permitted() on "nohash" platforms.
- Two commits to fix SIGBUS when using remap_pfn_range() seen on Power9
due to a workaround when using the nest MMU (GPUs, accelerators).
- Another fix to the VFIO code used by KVM, the previous fix had some
bugs which caused guests to not start in some configurations.
- A handful of other minor fixes.
Thanks to: Aneesh Kumar K.V, Benjamin Herrenschmidt, Christophe Leroy,
Hari Bathini, Luke Dashjr, Mahesh Salgaonkar, Nicholas Piggin, Paul
Mackerras, Srikar Dronamraju.
* tag 'powerpc-4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/mce: Fix SLB rebolting during MCE recovery path.
KVM: PPC: Book3S: Fix guest DMA when guest partially backed by THP pages
powerpc/mm/radix: Only need the Nest MMU workaround for R -> RW transition
powerpc/mm/books3s: Add new pte bit to mark pte temporarily invalid.
powerpc/nohash: fix pte_access_permitted()
powerpc/topology: Get topology for shared processors at boot
powerpc64/ftrace: Include ftrace.h needed for enable/disable calls
powerpc/powernv/pci: Work around races in PCI bridge enabling
powerpc/fadump: cleanup crash memory ranges support
powerpc/powernv: provide a console flush operation for opal hvc driver
powerpc/traps: Avoid rate limit messages from show unhandled signals
powerpc/64s: Fix PACA_IRQ_HARD_DIS accounting in idle_power4()
this_cpu_disable_ftrace and this_cpu_enable_ftrace are inlines in
ftrace.h Without it included, the build fails.
Fixes: a4bc64d305 ("powerpc64/ftrace: Disable ftrace during kvm entry/exit")
Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: Luke Dashjr <luke-jr+git@utopios.org>
Acked-by: Naveen N. Rao <naveen.n.rao at linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
For x86 this brings in PCID emulation and CR3 caching for shadow page
tables, nested VMX live migration, nested VMCS shadowing, an optimized
IPI hypercall, and some optimizations.
ARM will come next week.
There is a semantic conflict because tip also added an .init_platform
callback to kvm.c. Please keep the initializer from this branch,
and add a call to kvmclock_init (added by tip) inside kvm_init_platform
(added here).
Also, there is a backmerge from 4.18-rc6. This is because of a
refactoring that conflicted with a relatively late bugfix and
resulted in a particularly hellish conflict. Because the conflict
was only due to unfortunate timing of the bugfix, I backmerged and
rebased the refactoring rather than force the resolution on you.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull first set of KVM updates from Paolo Bonzini:
"PPC:
- minor code cleanups
x86:
- PCID emulation and CR3 caching for shadow page tables
- nested VMX live migration
- nested VMCS shadowing
- optimized IPI hypercall
- some optimizations
ARM will come next week"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (85 commits)
kvm: x86: Set highest physical address bits in non-present/reserved SPTEs
KVM/x86: Use CC_SET()/CC_OUT in arch/x86/kvm/vmx.c
KVM: X86: Implement PV IPIs in linux guest
KVM: X86: Add kvm hypervisor init time platform setup callback
KVM: X86: Implement "send IPI" hypercall
KVM/x86: Move X86_CR4_OSXSAVE check into kvm_valid_sregs()
KVM: x86: Skip pae_root shadow allocation if tdp enabled
KVM/MMU: Combine flushing remote tlb in mmu_set_spte()
KVM: vmx: skip VMWRITE of HOST_{FS,GS}_BASE when possible
KVM: vmx: skip VMWRITE of HOST_{FS,GS}_SEL when possible
KVM: vmx: always initialize HOST_{FS,GS}_BASE to zero during setup
KVM: vmx: move struct host_state usage to struct loaded_vmcs
KVM: vmx: compute need to reload FS/GS/LDT on demand
KVM: nVMX: remove a misleading comment regarding vmcs02 fields
KVM: vmx: rename __vmx_load_host_state() and vmx_save_host_state()
KVM: vmx: add dedicated utility to access guest's kernel_gs_base
KVM: vmx: track host_state.loaded using a loaded_vmcs pointer
KVM: vmx: refactor segmentation code in vmx_save_host_state()
kvm: nVMX: Fix fault priority for VMX operations
kvm: nVMX: Fix fault vector for VMX operation at CPL > 0
...
Notable changes:
- A fix for a bug in our page table fragment allocator, where a page table page
could be freed and reallocated for something else while still in use, leading
to memory corruption etc. The fix reuses pt_mm in struct page (x86 only) for
a powerpc only refcount.
- Fixes to our pkey support. Several are user-visible changes, but bring us in
to line with x86 behaviour and/or fix outright bugs. Thanks to Florian Weimer
for reporting many of these.
- A series to improve the hvc driver & related OPAL console code, which have
been seen to cause hardlockups at times. The hvc driver changes in particular
have been in linux-next for ~month.
- Increase our MAX_PHYSMEM_BITS to 128TB when SPARSEMEM_VMEMMAP=y.
- Remove Power8 DD1 and Power9 DD1 support, neither chip should be in use
anywhere other than as a paper weight.
- An optimised memcmp implementation using Power7-or-later VMX instructions
- Support for barrier_nospec on some NXP CPUs.
- Support for flushing the count cache on context switch on some IBM CPUs
(controlled by firmware), as a Spectre v2 mitigation.
- A series to enhance the information we print on unhandled signals to bring it
into line with other arches, including showing the offending VMA and dumping
the instructions around the fault.
Thanks to:
Aaro Koskinen, Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Alexey
Spirkov, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar,
Arnd Bergmann, Bartosz Golaszewski, Benjamin Herrenschmidt, Bharat Bhushan,
Bjoern Noetel, Boqun Feng, Breno Leitao, Bryant G. Ly, Camelia Groza,
Christophe Leroy, Christoph Hellwig, Cyril Bur, Dan Carpenter, Daniel Klamt,
Darren Stevens, Dave Young, David Gibson, Diana Craciun, Finn Thain, Florian
Weimer, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Geoff Levand,
Guenter Roeck, Gustavo Romero, Haren Myneni, Hari Bathini, Joel Stanley,
Jonathan Neuschäfer, Kees Cook, Madhavan Srinivasan, Mahesh Salgaonkar, Markus
Elfring, Mathieu Malaterre, Mauro S. M. Rodrigues, Michael Hanselmann, Michael
Neuling, Michael Schmitz, Mukesh Ojha, Murilo Opsfelder Araujo, Nicholas
Piggin, Parth Y Shah, Paul Mackerras, Paul Menzel, Ram Pai, Randy Dunlap,
Rashmica Gupta, Reza Arbab, Rodrigo R. Galvao, Russell Currey, Sam Bobroff,
Scott Wood, Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stan Johnson,
Thiago Jung Bauermann, Tyrel Datwyler, Vaibhav Jain, Vasant Hegde, Venkat Rao
B, zhong jiang.
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Merge tag 'powerpc-4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Notable changes:
- A fix for a bug in our page table fragment allocator, where a page
table page could be freed and reallocated for something else while
still in use, leading to memory corruption etc. The fix reuses
pt_mm in struct page (x86 only) for a powerpc only refcount.
- Fixes to our pkey support. Several are user-visible changes, but
bring us in to line with x86 behaviour and/or fix outright bugs.
Thanks to Florian Weimer for reporting many of these.
- A series to improve the hvc driver & related OPAL console code,
which have been seen to cause hardlockups at times. The hvc driver
changes in particular have been in linux-next for ~month.
- Increase our MAX_PHYSMEM_BITS to 128TB when SPARSEMEM_VMEMMAP=y.
- Remove Power8 DD1 and Power9 DD1 support, neither chip should be in
use anywhere other than as a paper weight.
- An optimised memcmp implementation using Power7-or-later VMX
instructions
- Support for barrier_nospec on some NXP CPUs.
- Support for flushing the count cache on context switch on some IBM
CPUs (controlled by firmware), as a Spectre v2 mitigation.
- A series to enhance the information we print on unhandled signals
to bring it into line with other arches, including showing the
offending VMA and dumping the instructions around the fault.
Thanks to: Aaro Koskinen, Akshay Adiga, Alastair D'Silva, Alexey
Kardashevskiy, Alexey Spirkov, Alistair Popple, Andrew Donnellan,
Aneesh Kumar K.V, Anju T Sudhakar, Arnd Bergmann, Bartosz Golaszewski,
Benjamin Herrenschmidt, Bharat Bhushan, Bjoern Noetel, Boqun Feng,
Breno Leitao, Bryant G. Ly, Camelia Groza, Christophe Leroy, Christoph
Hellwig, Cyril Bur, Dan Carpenter, Daniel Klamt, Darren Stevens, Dave
Young, David Gibson, Diana Craciun, Finn Thain, Florian Weimer,
Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Geoff Levand,
Guenter Roeck, Gustavo Romero, Haren Myneni, Hari Bathini, Joel
Stanley, Jonathan Neuschäfer, Kees Cook, Madhavan Srinivasan, Mahesh
Salgaonkar, Markus Elfring, Mathieu Malaterre, Mauro S. M. Rodrigues,
Michael Hanselmann, Michael Neuling, Michael Schmitz, Mukesh Ojha,
Murilo Opsfelder Araujo, Nicholas Piggin, Parth Y Shah, Paul
Mackerras, Paul Menzel, Ram Pai, Randy Dunlap, Rashmica Gupta, Reza
Arbab, Rodrigo R. Galvao, Russell Currey, Sam Bobroff, Scott Wood,
Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stan Johnson, Thiago
Jung Bauermann, Tyrel Datwyler, Vaibhav Jain, Vasant Hegde, Venkat
Rao, zhong jiang"
* tag 'powerpc-4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (234 commits)
powerpc/mm/book3s/radix: Add mapping statistics
powerpc/uaccess: Enable get_user(u64, *p) on 32-bit
powerpc/mm/hash: Remove unnecessary do { } while(0) loop
powerpc/64s: move machine check SLB flushing to mm/slb.c
powerpc/powernv/idle: Fix build error
powerpc/mm/tlbflush: update the mmu_gather page size while iterating address range
powerpc/mm: remove warning about ‘type’ being set
powerpc/32: Include setup.h header file to fix warnings
powerpc: Move `path` variable inside DEBUG_PROM
powerpc/powermac: Make some functions static
powerpc/powermac: Remove variable x that's never read
cxl: remove a dead branch
powerpc/powermac: Add missing include of header pmac.h
powerpc/kexec: Use common error handling code in setup_new_fdt()
powerpc/xmon: Add address lookup for percpu symbols
powerpc/mm: remove huge_pte_offset_and_shift() prototype
powerpc/lib: Use patch_site to patch copy_32 functions once cache is enabled
powerpc/pseries: Fix endianness while restoring of r3 in MCE handler.
powerpc/fadump: merge adjacent memory ranges to reduce PT_LOAD segements
powerpc/fadump: handle crash memory ranges array index overflow
...
asm/tlbflush.h is only needed for:
- using functions xxx_flush_tlb_xxx()
- using MMU_NO_CONTEXT
- including asm-generic/pgtable.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Commit 1e175d2 ("KVM: PPC: Book3S HV: Pack VCORE IDs to access full
VCPU ID space", 2018-07-25) added code that uses kvm->arch.emul_smt_mode
before any VCPUs are created. However, userspace can change
kvm->arch.emul_smt_mode at any time up until the first VCPU is created.
Hence it is (theoretically) possible for the check in
kvmppc_core_vcpu_create_hv() to race with another userspace thread
changing kvm->arch.emul_smt_mode.
This fixes it by moving the test that uses kvm->arch.emul_smt_mode into
the block where kvm->lock is held.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
It is not currently possible to create the full number of possible
VCPUs (KVM_MAX_VCPUS) on Power9 with KVM-HV when the guest uses fewer
threads per core than its core stride (or "VSMT mode"). This is
because the VCORE ID and XIVE offsets grow beyond KVM_MAX_VCPUS
even though the VCPU ID is less than KVM_MAX_VCPU_ID.
To address this, "pack" the VCORE ID and XIVE offsets by using
knowledge of the way the VCPU IDs will be used when there are fewer
guest threads per core than the core stride. The primary thread of
each core will always be used first. Then, if the guest uses more than
one thread per core, these secondary threads will sequentially follow
the primary in each core.
So, the only way an ID above KVM_MAX_VCPUS can be seen, is if the
VCPUs are being spaced apart, so at least half of each core is empty,
and IDs between KVM_MAX_VCPUS and (KVM_MAX_VCPUS * 2) can be mapped
into the second half of each core (4..7, in an 8-thread core).
Similarly, if IDs above KVM_MAX_VCPUS * 2 are seen, at least 3/4 of
each core is being left empty, and we can map down into the second and
third quarters of each core (2, 3 and 5, 6 in an 8-thread core).
Lastly, if IDs above KVM_MAX_VCPUS * 4 are seen, only the primary
threads are being used and 7/8 of the core is empty, allowing use of
the 1, 5, 3 and 7 thread slots.
(Strides less than 8 are handled similarly.)
This allows the VCORE ID or offset to be calculated quickly from the
VCPU ID or XIVE server numbers, without access to the VCPU structure.
[paulus@ozlabs.org - tidied up comment a little, changed some WARN_ONCE
to pr_devel, wrapped line, fixed id check.]
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The constants are 64bit but not explicitly declared UL resulting
in sparse warnings. Fix this by declaring the constants UL.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The call to of_find_compatible_node() is returning a pointer with
incremented refcount so it must be explicitly decremented after the
last use. As here it is only being used for checking of node presence
but the result is not actually used in the success path it can be
dropped immediately.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Fixes: commit f725758b89 ("KVM: PPC: Book3S HV: Use OPAL XICS emulation on POWER9")
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
POWER9 DD1 was never a product. It is no longer supported by upstream
firmware, and it is not effectively supported in Linux due to lack of
testing.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
[mpe: Remove arch_make_huge_pte() entirely]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
- Additional struct_size() conversions (Matthew, Kees)
- Explicitly reported overflow fixes (Silvio, Kees)
- Add missing kvcalloc() function (Kees)
- Treewide conversions of allocators to use either 2-factor argument
variant when available, or array_size() and array3_size() as needed (Kees)
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Merge tag 'overflow-v4.18-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull more overflow updates from Kees Cook:
"The rest of the overflow changes for v4.18-rc1.
This includes the explicit overflow fixes from Silvio, further
struct_size() conversions from Matthew, and a bug fix from Dan.
But the bulk of it is the treewide conversions to use either the
2-factor argument allocators (e.g. kmalloc(a * b, ...) into
kmalloc_array(a, b, ...) or the array_size() macros (e.g. vmalloc(a *
b) into vmalloc(array_size(a, b)).
Coccinelle was fighting me on several fronts, so I've done a bunch of
manual whitespace updates in the patches as well.
Summary:
- Error path bug fix for overflow tests (Dan)
- Additional struct_size() conversions (Matthew, Kees)
- Explicitly reported overflow fixes (Silvio, Kees)
- Add missing kvcalloc() function (Kees)
- Treewide conversions of allocators to use either 2-factor argument
variant when available, or array_size() and array3_size() as needed
(Kees)"
* tag 'overflow-v4.18-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (26 commits)
treewide: Use array_size in f2fs_kvzalloc()
treewide: Use array_size() in f2fs_kzalloc()
treewide: Use array_size() in f2fs_kmalloc()
treewide: Use array_size() in sock_kmalloc()
treewide: Use array_size() in kvzalloc_node()
treewide: Use array_size() in vzalloc_node()
treewide: Use array_size() in vzalloc()
treewide: Use array_size() in vmalloc()
treewide: devm_kzalloc() -> devm_kcalloc()
treewide: devm_kmalloc() -> devm_kmalloc_array()
treewide: kvzalloc() -> kvcalloc()
treewide: kvmalloc() -> kvmalloc_array()
treewide: kzalloc_node() -> kcalloc_node()
treewide: kzalloc() -> kcalloc()
treewide: kmalloc() -> kmalloc_array()
mm: Introduce kvcalloc()
video: uvesafb: Fix integer overflow in allocation
UBIFS: Fix potential integer overflow in allocation
leds: Use struct_size() in allocation
Convert intel uncore to struct_size
...
* ARM: lazy context-switching of FPSIMD registers on arm64, "split"
regions for vGIC redistributor
* s390: cleanups for nested, clock handling, crypto, storage keys and
control register bits
* x86: many bugfixes, implement more Hyper-V super powers,
implement lapic_timer_advance_ns even when the LAPIC timer
is emulated using the processor's VMX preemption timer. Two
security-related bugfixes at the top of the branch.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"Small update for KVM:
ARM:
- lazy context-switching of FPSIMD registers on arm64
- "split" regions for vGIC redistributor
s390:
- cleanups for nested
- clock handling
- crypto
- storage keys
- control register bits
x86:
- many bugfixes
- implement more Hyper-V super powers
- implement lapic_timer_advance_ns even when the LAPIC timer is
emulated using the processor's VMX preemption timer.
- two security-related bugfixes at the top of the branch"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (79 commits)
kvm: fix typo in flag name
kvm: x86: use correct privilege level for sgdt/sidt/fxsave/fxrstor access
KVM: x86: pass kvm_vcpu to kvm_read_guest_virt and kvm_write_guest_virt_system
KVM: x86: introduce linear_{read,write}_system
kvm: nVMX: Enforce cpl=0 for VMX instructions
kvm: nVMX: Add support for "VMWRITE to any supported field"
kvm: nVMX: Restrict VMX capability MSR changes
KVM: VMX: Optimize tscdeadline timer latency
KVM: docs: nVMX: Remove known limitations as they do not exist now
KVM: docs: mmu: KVM support exposing SLAT to guests
kvm: no need to check return value of debugfs_create functions
kvm: Make VM ioctl do valloc for some archs
kvm: Change return type to vm_fault_t
KVM: docs: mmu: Fix link to NPT presentation from KVM Forum 2008
kvm: x86: Amend the KVM_GET_SUPPORTED_CPUID API documentation
KVM: x86: hyperv: declare KVM_CAP_HYPERV_TLBFLUSH capability
KVM: x86: hyperv: simplistic HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}_EX implementation
KVM: x86: hyperv: simplistic HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE} implementation
KVM: introduce kvm_make_vcpus_request_mask() API
KVM: x86: hyperv: do rep check for each hypercall separately
...
Notable changes:
- Support for split PMD page table lock on 64-bit Book3S (Power8/9).
- Add support for HAVE_RELIABLE_STACKTRACE, so we properly support live
patching again.
- Add support for patching barrier_nospec in copy_from_user() and syscall entry.
- A couple of fixes for our data breakpoints on Book3S.
- A series from Nick optimising TLB/mm handling with the Radix MMU.
- Numerous small cleanups to squash sparse/gcc warnings from Mathieu Malaterre.
- Several series optimising various parts of the 32-bit code from Christophe Leroy.
- Removal of support for two old machines, "SBC834xE" and "C2K" ("GEFanuc,C2K"),
which is why the diffstat has so many deletions.
And many other small improvements & fixes.
There's a few out-of-area changes. Some minor ftrace changes OK'ed by Steve, and
a fix to our powernv cpuidle driver. Then there's a series touching mm, x86 and
fs/proc/task_mmu.c, which cleans up some details around pkey support. It was
ack'ed/reviewed by Ingo & Dave and has been in next for several weeks.
Thanks to:
Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Al Viro, Andrew
Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Arnd Bergmann, Balbir Singh,
Cédric Le Goater, Christophe Leroy, Christophe Lombard, Colin Ian King, Dave
Hansen, Fabio Estevam, Finn Thain, Frederic Barrat, Gautham R. Shenoy, Haren
Myneni, Hari Bathini, Ingo Molnar, Jonathan Neuschäfer, Josh Poimboeuf,
Kamalesh Babulal, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Greer, Mathieu
Malaterre, Matthew Wilcox, Michael Neuling, Michal Suchanek, Naveen N. Rao,
Nicholas Piggin, Nicolai Stange, Olof Johansson, Paul Gortmaker, Paul
Mackerras, Peter Rosin, Pridhiviraj Paidipeddi, Ram Pai, Rashmica Gupta, Ravi
Bangoria, Russell Currey, Sam Bobroff, Samuel Mendoza-Jonas, Segher
Boessenkool, Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stewart Smith,
Thiago Jung Bauermann, Torsten Duwe, Vaibhav Jain, Wei Yongjun, Wolfram Sang,
Yisheng Xie, YueHaibing.
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Merge tag 'powerpc-4.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Notable changes:
- Support for split PMD page table lock on 64-bit Book3S (Power8/9).
- Add support for HAVE_RELIABLE_STACKTRACE, so we properly support
live patching again.
- Add support for patching barrier_nospec in copy_from_user() and
syscall entry.
- A couple of fixes for our data breakpoints on Book3S.
- A series from Nick optimising TLB/mm handling with the Radix MMU.
- Numerous small cleanups to squash sparse/gcc warnings from Mathieu
Malaterre.
- Several series optimising various parts of the 32-bit code from
Christophe Leroy.
- Removal of support for two old machines, "SBC834xE" and "C2K"
("GEFanuc,C2K"), which is why the diffstat has so many deletions.
And many other small improvements & fixes.
There's a few out-of-area changes. Some minor ftrace changes OK'ed by
Steve, and a fix to our powernv cpuidle driver. Then there's a series
touching mm, x86 and fs/proc/task_mmu.c, which cleans up some details
around pkey support. It was ack'ed/reviewed by Ingo & Dave and has
been in next for several weeks.
Thanks to: Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Al
Viro, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Arnd
Bergmann, Balbir Singh, Cédric Le Goater, Christophe Leroy, Christophe
Lombard, Colin Ian King, Dave Hansen, Fabio Estevam, Finn Thain,
Frederic Barrat, Gautham R. Shenoy, Haren Myneni, Hari Bathini, Ingo
Molnar, Jonathan Neuschäfer, Josh Poimboeuf, Kamalesh Babulal,
Madhavan Srinivasan, Mahesh Salgaonkar, Mark Greer, Mathieu Malaterre,
Matthew Wilcox, Michael Neuling, Michal Suchanek, Naveen N. Rao,
Nicholas Piggin, Nicolai Stange, Olof Johansson, Paul Gortmaker, Paul
Mackerras, Peter Rosin, Pridhiviraj Paidipeddi, Ram Pai, Rashmica
Gupta, Ravi Bangoria, Russell Currey, Sam Bobroff, Samuel
Mendoza-Jonas, Segher Boessenkool, Shilpasri G Bhat, Simon Guo,
Souptick Joarder, Stewart Smith, Thiago Jung Bauermann, Torsten Duwe,
Vaibhav Jain, Wei Yongjun, Wolfram Sang, Yisheng Xie, YueHaibing"
* tag 'powerpc-4.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (251 commits)
powerpc/64s/radix: Fix missing ptesync in flush_cache_vmap
cpuidle: powernv: Fix promotion from snooze if next state disabled
powerpc: fix build failure by disabling attribute-alias warning in pci_32
ocxl: Fix missing unlock on error in afu_ioctl_enable_p9_wait()
powerpc-opal: fix spelling mistake "Uniterrupted" -> "Uninterrupted"
powerpc: fix spelling mistake: "Usupported" -> "Unsupported"
powerpc/pkeys: Detach execute_only key on !PROT_EXEC
powerpc/powernv: copy/paste - Mask SO bit in CR
powerpc: Remove core support for Marvell mv64x60 hostbridges
powerpc/boot: Remove core support for Marvell mv64x60 hostbridges
powerpc/boot: Remove support for Marvell mv64x60 i2c controller
powerpc/boot: Remove support for Marvell MPSC serial controller
powerpc/embedded6xx: Remove C2K board support
powerpc/lib: optimise PPC32 memcmp
powerpc/lib: optimise 32 bits __clear_user()
powerpc/time: inline arch_vtime_task_switch()
powerpc/Makefile: set -mcpu=860 flag for the 8xx
powerpc: Implement csum_ipv6_magic in assembly
powerpc/32: Optimise __csum_partial()
powerpc/lib: Adjust .balign inside string functions for PPC32
...
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
This cleans up the error handling a lot, as this code will never get
hit.
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christoffer Dall <christoffer.dall@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim KrÄmář" <rkrcmar@redhat.com>
Cc: Arvind Yadav <arvind.yadav.cs@gmail.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: kvm-ppc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: kvmarm@lists.cs.columbia.edu
Cc: kvm@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The radix guest code can has fewer restrictions about what context it
can run in, so move this flushing out of assembly and have it use the
Linux TLB flush implementations introduced previously.
This allows powerpc:tlbie trace events to be used.
This changes the tlbiel sequence to only execute RIC=2 flush once on
the first set flushed, then RIC=0 for the rest of the sets. The end
result of the flush should be unchanged. This matches the local PID
flush pattern that was introduced in a5998fcb92 ("powerpc/mm/radix:
Optimise tlbiel flush all case").
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This patch moves nip/ctr/lr/xer registers from scattered places in
kvm_vcpu_arch to pt_regs structure.
cr register is "unsigned long" in pt_regs and u32 in vcpu->arch.
It will need more consideration and may move in later patches.
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Although Linux doesn't use PURR and SPURR ((Scaled) Processor
Utilization of Resources Register), other OSes depend on them.
On POWER8 they count at a rate depending on whether the VCPU is
idle or running, the activity of the VCPU, and the value in the
RWMR (Region-Weighting Mode Register). Hardware expects the
hypervisor to update the RWMR when a core is dispatched to reflect
the number of online VCPUs in the vcore.
This adds code to maintain a count in the vcore struct indicating
how many VCPUs are online. In kvmppc_run_core we use that count
to set the RWMR register on POWER8. If the core is split because
of a static or dynamic micro-threading mode, we use the value for
8 threads. The RWMR value is not relevant when the host is
executing because Linux does not use the PURR or SPURR register,
so we don't bother saving and restoring the host value.
For the sake of old userspace which does not set the KVM_REG_PPC_ONLINE
register, we set online to 1 if it was 0 at the time of a KVM_RUN
ioctl.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This adds a new KVM_REG_PPC_ONLINE register which userspace can set
to 0 or 1 via the GET/SET_ONE_REG interface to indicate whether it
considers the VCPU to be offline (0), that is, not currently running,
or online (1). This will be used in a later patch to configure the
register which controls PURR and SPURR accumulation.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Currently, the HV KVM guest entry/exit code adds the timebase offset
from the vcore struct to the timebase on guest entry, and subtracts
it on guest exit. Which is fine, except that it is possible for
userspace to change the offset using the SET_ONE_REG interface while
the vcore is running, as there is only one timebase offset per vcore
but potentially multiple VCPUs in the vcore. If that were to happen,
KVM would subtract a different offset on guest exit from that which
it had added on guest entry, leading to the timebase being out of sync
between cores in the host, which then leads to bad things happening
such as hangs and spurious watchdog timeouts.
To fix this, we add a new field 'tb_offset_applied' to the vcore struct
which stores the offset that is currently applied to the timebase.
This value is set from the vcore tb_offset field on guest entry, and
is what is subtracted from the timebase on guest exit. Since it is
zero when the timebase offset is not applied, we can simplify the
logic in kvmhv_start_timing and kvmhv_accumulate_time.
In addition, we had secondary threads reading the timebase while
running concurrently with code on the primary thread which would
eventually add or subtract the timebase offset from the timebase.
This occurred while saving or restoring the DEC register value on
the secondary threads. Although no specific incorrect behaviour has
been observed, this is a race which should be fixed. To fix it, we
move the DEC saving code to just before we call kvmhv_commence_exit,
and the DEC restoring code to after the point where we have waited
for the primary thread to switch the MMU context and add the timebase
offset. That way we are sure that the timebase contains the guest
timebase value in both cases.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
During guest entry/exit, we switch over to/from the guest MMU context
and we cannot take exceptions in the hypervisor code.
Since ftrace may be enabled and since it can result in us taking a trap,
disable ftrace by setting paca->ftrace_enabled to zero. There are two
paths through which we enter/exit a guest:
1. If we are the vcore runner, then we enter the guest via
__kvmppc_vcore_entry() and we disable ftrace around this. This is always
the case for Power9, and for the primary thread on Power8.
2. If we are a secondary thread in Power8, then we would be in nap due
to SMT being disabled. We are woken up by an IPI to enter the guest. In
this scenario, we enter the guest through kvm_start_guest(). We disable
ftrace at this point. In this scenario, ftrace would only get re-enabled
on the secondary thread when SMT is re-enabled (via start_secondary()).
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
- VHE optimizations
- EL2 address space randomization
- speculative execution mitigations ("variant 3a", aka execution past invalid
privilege register access)
- bugfixes and cleanups
PPC:
- improvements for the radix page fault handler for HV KVM on POWER9
s390:
- more kvm stat counters
- virtio gpu plumbing
- documentation
- facilities improvements
x86:
- support for VMware magic I/O port and pseudo-PMCs
- AMD pause loop exiting
- support for AMD core performance extensions
- support for synchronous register access
- expose nVMX capabilities to userspace
- support for Hyper-V signaling via eventfd
- use Enlightened VMCS when running on Hyper-V
- allow userspace to disable MWAIT/HLT/PAUSE vmexits
- usual roundup of optimizations and nested virtualization bugfixes
Generic:
- API selftest infrastructure (though the only tests are for x86 as of now)
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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:
- VHE optimizations
- EL2 address space randomization
- speculative execution mitigations ("variant 3a", aka execution past
invalid privilege register access)
- bugfixes and cleanups
PPC:
- improvements for the radix page fault handler for HV KVM on POWER9
s390:
- more kvm stat counters
- virtio gpu plumbing
- documentation
- facilities improvements
x86:
- support for VMware magic I/O port and pseudo-PMCs
- AMD pause loop exiting
- support for AMD core performance extensions
- support for synchronous register access
- expose nVMX capabilities to userspace
- support for Hyper-V signaling via eventfd
- use Enlightened VMCS when running on Hyper-V
- allow userspace to disable MWAIT/HLT/PAUSE vmexits
- usual roundup of optimizations and nested virtualization bugfixes
Generic:
- API selftest infrastructure (though the only tests are for x86 as
of now)"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (174 commits)
kvm: x86: fix a prototype warning
kvm: selftests: add sync_regs_test
kvm: selftests: add API testing infrastructure
kvm: x86: fix a compile warning
KVM: X86: Add Force Emulation Prefix for "emulate the next instruction"
KVM: X86: Introduce handle_ud()
KVM: vmx: unify adjacent #ifdefs
x86: kvm: hide the unused 'cpu' variable
KVM: VMX: remove bogus WARN_ON in handle_ept_misconfig
Revert "KVM: X86: Fix SMRAM accessing even if VM is shutdown"
kvm: Add emulation for movups/movupd
KVM: VMX: raise internal error for exception during invalid protected mode state
KVM: nVMX: Optimization: Dont set KVM_REQ_EVENT when VMExit with nested_run_pending
KVM: nVMX: Require immediate-exit when event reinjected to L2 and L1 event pending
KVM: x86: Fix misleading comments on handling pending exceptions
KVM: x86: Rename interrupt.pending to interrupt.injected
KVM: VMX: No need to clear pending NMI/interrupt on inject realmode interrupt
x86/kvm: use Enlightened VMCS when running on Hyper-V
x86/hyper-v: detect nested features
x86/hyper-v: define struct hv_enlightened_vmcs and clean field bits
...
Notable changes:
- Support for 4PB user address space on 64-bit, opt-in via mmap().
- Removal of POWER4 support, which was accidentally broken in 2016 and no one
noticed, and blocked use of some modern instructions.
- Workarounds so that the hypervisor can enable Transactional Memory on Power9.
- A series to disable the DAWR (Data Address Watchpoint Register) on Power9.
- More information displayed in the meltdown/spectre_v1/v2 sysfs files.
- A vpermxor (Power8 Altivec) implementation for the raid6 Q Syndrome.
- A big series to make the allocation of our pacas (per cpu area), kernel page
tables, and per-cpu stacks NUMA aware when using the Radix MMU on Power9.
And as usual many fixes, reworks and cleanups.
Thanks to:
Aaro Koskinen, Alexandre Belloni, Alexey Kardashevskiy, Alistair Popple, Andy
Shevchenko, Aneesh Kumar K.V, Anshuman Khandual, Balbir Singh, Benjamin
Herrenschmidt, Christophe Leroy, Christophe Lombard, Cyril Bur, Daniel Axtens,
Dave Young, Finn Thain, Frederic Barrat, Gustavo Romero, Horia Geantă,
Jonathan Neuschäfer, Kees Cook, Larry Finger, Laurent Dufour, Laurent Vivier,
Logan Gunthorpe, Madhavan Srinivasan, Mark Greer, Mark Hairgrove, Markus
Elfring, Mathieu Malaterre, Matt Brown, Matt Evans, Mauricio Faria de
Oliveira, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Paul Mackerras,
Philippe Bergheaud, Ram Pai, Rob Herring, Sam Bobroff, Segher Boessenkool,
Simon Guo, Simon Horman, Stewart Smith, Sukadev Bhattiprolu, Suraj Jitindar
Singh, Thiago Jung Bauermann, Vaibhav Jain, Vaidyanathan Srinivasan, Vasant
Hegde, Wei Yongjun.
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Merge tag 'powerpc-4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Notable changes:
- Support for 4PB user address space on 64-bit, opt-in via mmap().
- Removal of POWER4 support, which was accidentally broken in 2016
and no one noticed, and blocked use of some modern instructions.
- Workarounds so that the hypervisor can enable Transactional Memory
on Power9.
- A series to disable the DAWR (Data Address Watchpoint Register) on
Power9.
- More information displayed in the meltdown/spectre_v1/v2 sysfs
files.
- A vpermxor (Power8 Altivec) implementation for the raid6 Q
Syndrome.
- A big series to make the allocation of our pacas (per cpu area),
kernel page tables, and per-cpu stacks NUMA aware when using the
Radix MMU on Power9.
And as usual many fixes, reworks and cleanups.
Thanks to: Aaro Koskinen, Alexandre Belloni, Alexey Kardashevskiy,
Alistair Popple, Andy Shevchenko, Aneesh Kumar K.V, Anshuman Khandual,
Balbir Singh, Benjamin Herrenschmidt, Christophe Leroy, Christophe
Lombard, Cyril Bur, Daniel Axtens, Dave Young, Finn Thain, Frederic
Barrat, Gustavo Romero, Horia Geantă, Jonathan Neuschäfer, Kees Cook,
Larry Finger, Laurent Dufour, Laurent Vivier, Logan Gunthorpe,
Madhavan Srinivasan, Mark Greer, Mark Hairgrove, Markus Elfring,
Mathieu Malaterre, Matt Brown, Matt Evans, Mauricio Faria de Oliveira,
Michael Neuling, Naveen N. Rao, Nicholas Piggin, Paul Mackerras,
Philippe Bergheaud, Ram Pai, Rob Herring, Sam Bobroff, Segher
Boessenkool, Simon Guo, Simon Horman, Stewart Smith, Sukadev
Bhattiprolu, Suraj Jitindar Singh, Thiago Jung Bauermann, Vaibhav
Jain, Vaidyanathan Srinivasan, Vasant Hegde, Wei Yongjun"
* tag 'powerpc-4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (207 commits)
powerpc/64s/idle: Fix restore of AMOR on POWER9 after deep sleep
powerpc/64s: Fix POWER9 DD2.2 and above in cputable features
powerpc/64s: Fix pkey support in dt_cpu_ftrs, add CPU_FTR_PKEY bit
powerpc/64s: Fix dt_cpu_ftrs to have restore_cpu clear unwanted LPCR bits
Revert "powerpc/64s/idle: POWER9 ESL=0 stop avoid save/restore overhead"
powerpc: iomap.c: introduce io{read|write}64_{lo_hi|hi_lo}
powerpc: io.h: move iomap.h include so that it can use readq/writeq defs
cxl: Fix possible deadlock when processing page faults from cxllib
powerpc/hw_breakpoint: Only disable hw breakpoint if cpu supports it
powerpc/mm/radix: Update command line parsing for disable_radix
powerpc/mm/radix: Parse disable_radix commandline correctly.
powerpc/mm/hugetlb: initialize the pagetable cache correctly for hugetlb
powerpc/mm/radix: Update pte fragment count from 16 to 256 on radix
powerpc/mm/keys: Update documentation and remove unnecessary check
powerpc/64s/idle: POWER9 ESL=0 stop avoid save/restore overhead
powerpc/64s/idle: Consolidate power9_offline_stop()/power9_idle_stop()
powerpc/powernv: Always stop secondaries before reboot/shutdown
powerpc: hard disable irqs in smp_send_stop loop
powerpc: use NMI IPI for smp_send_stop
powerpc/powernv: Fix SMT4 forcing idle code
...
arch/powerpc/kvm/book3s_hv.c: In function ‘kvmppc_h_set_mode’:
arch/powerpc/kvm/book3s_hv.c:745:8: error: implicit declaration of function ‘ppc_breakpoint_available’
if (!ppc_breakpoint_available())
^~~~~~~~~~~~~~~~~~~~~~~~
Fixes: 398e712c00 ("KVM: PPC: Book3S HV: Return error from h_set_mode(SET_DAWR) on POWER9")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Bring in yet another series that touches KVM code, and might need to
be merged into the kvm-ppc branch to resolve conflicts.
This required some changes in pnv_power9_force_smt4_catch/release()
due to the paca array becomming an array of pointers.
We no longer allocate lppacas in an array, so this patch removes the
1kB static alignment for the structure, and enforces the PAPR
alignment requirements at allocation time. We can not reduce the 1kB
allocation size however, due to existing KVM hypervisors.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Change the paca array into an array of pointers to pacas. Allocate
pacas individually.
This allows flexibility in where the PACAs are allocated. Future work
will allocate them node-local. Platforms that don't have address limits
on PACAs would be able to defer PACA allocations until later in boot
rather than allocate all possible ones up-front then freeing unused.
This is slightly more overhead (one additional indirection) for cross
CPU paca references, but those aren't too common.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Return H_P2 on a h_set_mode(SET_DAWR) on POWER9 where the DAWR is
disabled.
Current Linux guests ignore this error, so they will silently not get
the DAWR (sigh). The same error code is being used by POWERVM in this
case.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
POWER9 has hardware bugs relating to transactional memory and thread
reconfiguration (changes to hardware SMT mode). Specifically, the core
does not have enough storage to store a complete checkpoint of all the
architected state for all four threads. The DD2.2 version of POWER9
includes hardware modifications designed to allow hypervisor software
to implement workarounds for these problems. This patch implements
those workarounds in KVM code so that KVM guests see a full, working
transactional memory implementation.
The problems center around the use of TM suspended state, where the
CPU has a checkpointed state but execution is not transactional. The
workaround is to implement a "fake suspend" state, which looks to the
guest like suspended state but the CPU does not store a checkpoint.
In this state, any instruction that would cause a transition to
transactional state (rfid, rfebb, mtmsrd, tresume) or would use the
checkpointed state (treclaim) causes a "soft patch" interrupt (vector
0x1500) to the hypervisor so that it can be emulated. The trechkpt
instruction also causes a soft patch interrupt.
On POWER9 DD2.2, we avoid returning to the guest in any state which
would require a checkpoint to be present. The trechkpt in the guest
entry path which would normally create that checkpoint is replaced by
either a transition to fake suspend state, if the guest is in suspend
state, or a rollback to the pre-transactional state if the guest is in
transactional state. Fake suspend state is indicated by a flag in the
PACA plus a new bit in the PSSCR. The new PSSCR bit is write-only and
reads back as 0.
On exit from the guest, if the guest is in fake suspend state, we still
do the treclaim instruction as we would in real suspend state, in order
to get into non-transactional state, but we do not save the resulting
register state since there was no checkpoint.
Emulation of the instructions that cause a softpatch interrupt is
handled in two paths. If the guest is in real suspend mode, we call
kvmhv_p9_tm_emulation_early() to handle the cases where the guest is
transitioning to transactional state. This is called before we do the
treclaim in the guest exit path; because we haven't done treclaim, we
can get back to the guest with the transaction still active. If the
instruction is a case that kvmhv_p9_tm_emulation_early() doesn't
handle, or if the guest is in fake suspend state, then we proceed to
do the complete guest exit path and subsequently call
kvmhv_p9_tm_emulation() in host context with the MMU on. This handles
all the cases including the cases that generate program interrupts
(illegal instruction or TM Bad Thing) and facility unavailable
interrupts.
The emulation is reasonably straightforward and is mostly concerned
with checking for exception conditions and updating the state of
registers such as MSR and CR0. The treclaim emulation takes care to
ensure that the TEXASR register gets updated as if it were the guest
treclaim instruction that had done failure recording, not the treclaim
done in hypervisor state in the guest exit path.
With this, the KVM_CAP_PPC_HTM capability returns true (1) even if
transactional memory is not available to host userspace.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Since commit fb1522e099 ("KVM: update to new mmu_notifier semantic
v2", 2017-08-31), the MMU notifier code in KVM no longer calls the
kvm_unmap_hva callback. This removes the PPC implementations of
kvm_unmap_hva().
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Since commit 8b24e69fc4 ("KVM: PPC: Book3S HV: Close race with testing
for signals on guest entry"), if CONFIG_VIRT_CPU_ACCOUNTING_GEN is set, the
guest time is not accounted to guest time and user time, but instead to
system time.
This is because guest_enter()/guest_exit() are called while interrupts
are disabled and the tick counter cannot be updated between them.
To fix that, move guest_exit() after local_irq_enable(), and as
guest_enter() is called with IRQ disabled, call guest_enter_irqoff()
instead.
Fixes: 8b24e69fc4 ("KVM: PPC: Book3S HV: Close race with testing for signals on guest entry")
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The current code for initializing the VRMA (virtual real memory area)
for HPT guests requires the page size of the backing memory to be one
of 4kB, 64kB or 16MB. With a radix host we have the possibility that
the backing memory page size can be 2MB or 1GB. In these cases, if the
guest switches to HPT mode, KVM will not initialize the VRMA and the
guest will fail to run.
In fact it is not necessary that the VRMA page size is the same as the
backing memory page size; any VRMA page size less than or equal to the
backing memory page size is acceptable. Therefore we now choose the
largest page size out of the set {4k, 64k, 16M} which is not larger
than the backing memory page size.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
ARM:
- Include icache invalidation optimizations, improving VM startup time
- Support for forwarded level-triggered interrupts, improving
performance for timers and passthrough platform devices
- A small fix for power-management notifiers, and some cosmetic changes
PPC:
- Add MMIO emulation for vector loads and stores
- Allow HPT guests to run on a radix host on POWER9 v2.2 CPUs without
requiring the complex thread synchronization of older CPU versions
- Improve the handling of escalation interrupts with the XIVE interrupt
controller
- Support decrement register migration
- Various cleanups and bugfixes.
s390:
- Cornelia Huck passed maintainership to Janosch Frank
- Exitless interrupts for emulated devices
- Cleanup of cpuflag handling
- kvm_stat counter improvements
- VSIE improvements
- mm cleanup
x86:
- Hypervisor part of SEV
- UMIP, RDPID, and MSR_SMI_COUNT emulation
- Paravirtualized TLB shootdown using the new KVM_VCPU_PREEMPTED bit
- Allow guests to see TOPOEXT, GFNI, VAES, VPCLMULQDQ, and more AVX512
features
- Show vcpu id in its anonymous inode name
- Many fixes and cleanups
- Per-VCPU MSR bitmaps (already merged through x86/pti branch)
- Stable KVM clock when nesting on Hyper-V (merged through x86/hyperv)
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Merge tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Radim Krčmář:
"ARM:
- icache invalidation optimizations, improving VM startup time
- support for forwarded level-triggered interrupts, improving
performance for timers and passthrough platform devices
- a small fix for power-management notifiers, and some cosmetic
changes
PPC:
- add MMIO emulation for vector loads and stores
- allow HPT guests to run on a radix host on POWER9 v2.2 CPUs without
requiring the complex thread synchronization of older CPU versions
- improve the handling of escalation interrupts with the XIVE
interrupt controller
- support decrement register migration
- various cleanups and bugfixes.
s390:
- Cornelia Huck passed maintainership to Janosch Frank
- exitless interrupts for emulated devices
- cleanup of cpuflag handling
- kvm_stat counter improvements
- VSIE improvements
- mm cleanup
x86:
- hypervisor part of SEV
- UMIP, RDPID, and MSR_SMI_COUNT emulation
- paravirtualized TLB shootdown using the new KVM_VCPU_PREEMPTED bit
- allow guests to see TOPOEXT, GFNI, VAES, VPCLMULQDQ, and more
AVX512 features
- show vcpu id in its anonymous inode name
- many fixes and cleanups
- per-VCPU MSR bitmaps (already merged through x86/pti branch)
- stable KVM clock when nesting on Hyper-V (merged through
x86/hyperv)"
* tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (197 commits)
KVM: PPC: Book3S: Add MMIO emulation for VMX instructions
KVM: PPC: Book3S HV: Branch inside feature section
KVM: PPC: Book3S HV: Make HPT resizing work on POWER9
KVM: PPC: Book3S HV: Fix handling of secondary HPTEG in HPT resizing code
KVM: PPC: Book3S PR: Fix broken select due to misspelling
KVM: x86: don't forget vcpu_put() in kvm_arch_vcpu_ioctl_set_sregs()
KVM: PPC: Book3S PR: Fix svcpu copying with preemption enabled
KVM: PPC: Book3S HV: Drop locks before reading guest memory
kvm: x86: remove efer_reload entry in kvm_vcpu_stat
KVM: x86: AMD Processor Topology Information
x86/kvm/vmx: do not use vm-exit instruction length for fast MMIO when running nested
kvm: embed vcpu id to dentry of vcpu anon inode
kvm: Map PFN-type memory regions as writable (if possible)
x86/kvm: Make it compile on 32bit and with HYPYERVISOR_GUEST=n
KVM: arm/arm64: Fixup userspace irqchip static key optimization
KVM: arm/arm64: Fix userspace_irqchip_in_use counting
KVM: arm/arm64: Fix incorrect timer_is_pending logic
MAINTAINERS: update KVM/s390 maintainers
MAINTAINERS: add Halil as additional vfio-ccw maintainer
MAINTAINERS: add David as a reviewer for KVM/s390
...
Running with CONFIG_DEBUG_ATOMIC_SLEEP reveals that HV KVM tries to
read guest memory, in order to emulate guest instructions, while
preempt is disabled and a vcore lock is held. This occurs in
kvmppc_handle_exit_hv(), called from post_guest_process(), when
emulating guest doorbell instructions on POWER9 systems, and also
when checking whether we have hit a hypervisor breakpoint.
Reading guest memory can cause a page fault and thus cause the
task to sleep, so we need to avoid reading guest memory while
holding a spinlock or when preempt is disabled.
To fix this, we move the preempt_enable() in kvmppc_run_core() to
before the loop that calls post_guest_process() for each vcore that
has just run, and we drop and re-take the vcore lock around the calls
to kvmppc_emulate_debug_inst() and kvmppc_emulate_doorbell_instr().
Dropping the lock is safe with respect to the iteration over the
runnable vcpus in post_guest_process(); for_each_runnable_thread
is actually safe to use locklessly. It is possible for a vcpu
to become runnable and add itself to the runnable_threads array
(code near the beginning of kvmppc_run_vcpu()) and then get included
in the iteration in post_guest_process despite the fact that it
has not just run. This is benign because vcpu->arch.trap and
vcpu->arch.ceded will be zero.
Cc: stable@vger.kernel.org # v4.13+
Fixes: 579006944e ("KVM: PPC: Book3S HV: Virtualize doorbell facility on POWER9")
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Symbolic macros are unintuitive and hard to read, whereas octal constants
are much easier to interpret. Replace macros for the basic permission
flags (user/group/other read/write/execute) with numeric constants
instead, across the whole powerpc tree.
Introducing a significant number of changes across the tree for no runtime
benefit isn't exactly desirable, but so long as these macros are still
used in the tree people will keep sending patches that add them. Not only
are they hard to parse at a glance, there are multiple ways of coming to
the same value (as you can see with 0444 and 0644 in this patch) which
hurts readability.
Signed-off-by: Russell Currey <ruscur@russell.cc>
Reviewed-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The prodded flag is only cleared at the beginning of H_CEDE,
so every time we have an escalation, we will cause the *next*
H_CEDE to return immediately.
Instead use a dedicated "irq_pending" flag to indicate that
a guest interrupt is pending for the VCPU. We don't reuse the
existing exception bitmap so as to avoid expensive atomic ops.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
POWER9 chip versions starting with "Nimbus" v2.2 can support running
with some threads of a core in HPT mode and others in radix mode.
This means that we don't have to prohibit independent-threads mode
when running a HPT guest on a radix host, and we don't have to do any
of the synchronization between threads that was introduced in commit
c01015091a ("KVM: PPC: Book3S HV: Run HPT guests on POWER9 radix
hosts", 2017-10-19).
Rather than using up another CPU feature bit, we just do an
explicit test on the PVR (processor version register) at module
startup time to determine whether we have to take steps to avoid
having some threads in HPT mode and some in radix mode (so-called
"mixed mode"). We test for "Nimbus" (indicated by 0 or 1 in the top
nibble of the lower 16 bits) v2.2 or later, or "Cumulus" (indicated by
2 or 3 in that nibble) v1.1 or later.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This adds a register identifier for use with the one_reg interface
to allow the decrementer expiry time to be read and written by
userspace. The decrementer expiry time is in guest timebase units
and is equal to the sum of the decrementer and the guest timebase.
(The expiry time is used rather than the decrementer value itself
because the expiry time is not constantly changing, though the
decrementer value is, while the guest vcpu is not running.)
Without this, a guest vcpu migrated to a new host will see its
decrementer set to some random value. On POWER8 and earlier, the
decrementer is 32 bits wide and counts down at 512MHz, so the
guest vcpu will potentially see no decrementer interrupts for up
to about 4 seconds, which will lead to a stall. With POWER9, the
decrementer is now 56 bits side, so the stall can be much longer
(up to 2.23 years) and more noticeable.
To help work around the problem in cases where userspace has not been
updated to migrate the decrementer expiry time, we now set the
default decrementer expiry at vcpu creation time to the current time
rather than the maximum possible value. This should mean an
immediate decrementer interrupt when a migrated vcpu starts
running. In cases where the decrementer is 32 bits wide and more
than 4 seconds elapse between the creation of the vcpu and when it
first runs, the decrementer would have wrapped around to positive
values and there may still be a stall - but this is no worse than
the current situation. In the large-decrementer case, we are sure
to get an immediate decrementer interrupt (assuming the time from
vcpu creation to first run is less than 2.23 years) and we thus
avoid a very long stall.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This corrects the test that determines whether a vcpu that has just
become able to run in the guest (e.g. it has just finished handling
a hypercall or hypervisor page fault) and whose virtual core is
already running somewhere as a "piggybacked" vcore can start
immediately or not. (A piggybacked vcore is one which is executing
along with another vcore as a result of dynamic micro-threading.)
Previously the test tried to lock the piggybacked vcore using
spin_trylock, which would always fail because the vcore was already
locked, and so the vcpu would have to wait until its vcore exited
the guest before it could enter.
In fact the vcpu can enter if its vcore is in VCORE_PIGGYBACK state
and not already exiting (or exited) the guest, so the test in
VCORE_PIGGYBACK state is basically the same as for VCORE_RUNNING
state.
Coverity detected this as a double unlock issue, which it isn't
because the spin_trylock would always fail. This will fix the
apparent double unlock as well.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This removes a statement that has no effect. It should have been
removed in commit 898b25b202 ("KVM: PPC: Book3S HV: Simplify dynamic
micro-threading code", 2017-06-22) along with the loop over the
piggy-backed virtual cores.
This issue was reported by Coverity.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This fixes two errors that prevent a guest using the HPT MMU from
successfully migrating to a POWER9 host in radix MMU mode, or resizing
its HPT when running on a radix host.
The first bug was that commit 8dc6cca556 ("KVM: PPC: Book3S HV:
Don't rely on host's page size information", 2017-09-11) missed two
uses of hpte_base_page_size(), one in the HPT rehashing code and
one in kvm_htab_write() (which is used on the destination side in
migrating a HPT guest). Instead we use kvmppc_hpte_base_page_shift().
Having the shift count means that we can use left and right shifts
instead of multiplication and division in a few places.
Along the way, this adds a check in kvm_htab_write() to ensure that the
page size encoding in the incoming HPTEs is recognized, and if not
return an EINVAL error to userspace.
The second bug was that kvm_htab_write was performing some but not all
of the functions of kvmhv_setup_mmu(), resulting in the destination VM
being left in radix mode as far as the hardware is concerned. The
simplest fix for now is make kvm_htab_write() call
kvmppc_setup_partition_table() like kvmppc_hv_setup_htab_rma() does.
In future it would be better to refactor the code more extensively
to remove the duplication.
Fixes: 8dc6cca556 ("KVM: PPC: Book3S HV: Don't rely on host's page size information")
Fixes: 7a84084c60 ("KVM: PPC: Book3S HV: Set partition table rather than SDR1 on POWER9")
Reported-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Tested-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
