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Author SHA1 Message Date
Mike Kravetz
e700898fa0 hugetlb: really allocate vma lock for all sharable vmas 
Commit bbff39cc6c ("hugetlb: allocate vma lock for all sharable vmas")
removed the pmd sharable checks in the vma lock helper routines.  However,
it left the functional version of helper routines behind #ifdef
CONFIG_ARCH_WANT_HUGE_PMD_SHARE.  Therefore, the vma lock is not being
used for sharable vmas on architectures that do not support pmd sharing. 
On these architectures, a potential fault/truncation race is exposed that
could leave pages in a hugetlb file past i_size until the file is removed.

Move the functional vma lock helpers outside the ifdef, and remove the
non-functional stubs.  Since the vma lock is not just for pmd sharing,
rename the routine __vma_shareable_flags_pmd.

Link: https://lkml.kernel.org/r/20221212235042.178355-1-mike.kravetz@oracle.com
Fixes: bbff39cc6c ("hugetlb: allocate vma lock for all sharable vmas")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: James Houghton <jthoughton@google.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-12-21 14:31:52 -08:00
Linus Torvalds
8fa590bf34 ARM64: 
* Enable the per-vcpu dirty-ring tracking mechanism, together with an
   option to keep the good old dirty log around for pages that are
   dirtied by something other than a vcpu.
 
 * Switch to the relaxed parallel fault handling, using RCU to delay
   page table reclaim and giving better performance under load.
 
 * Relax the MTE ABI, allowing a VMM to use the MAP_SHARED mapping option,
   which multi-process VMMs such as crosvm rely on (see merge commit 382b5b87a9:
   "Fix a number of issues with MTE, such as races on the tags being
   initialised vs the PG_mte_tagged flag as well as the lack of support
   for VM_SHARED when KVM is involved.  Patches from Catalin Marinas and
   Peter Collingbourne").
 
 * Merge the pKVM shadow vcpu state tracking that allows the hypervisor
   to have its own view of a vcpu, keeping that state private.
 
 * Add support for the PMUv3p5 architecture revision, bringing support
   for 64bit counters on systems that support it, and fix the
   no-quite-compliant CHAIN-ed counter support for the machines that
   actually exist out there.
 
 * Fix a handful of minor issues around 52bit VA/PA support (64kB pages
   only) as a prefix of the oncoming support for 4kB and 16kB pages.
 
 * Pick a small set of documentation and spelling fixes, because no
   good merge window would be complete without those.
 
 s390:
 
 * Second batch of the lazy destroy patches
 
 * First batch of KVM changes for kernel virtual != physical address support
 
 * Removal of a unused function
 
 x86:
 
 * Allow compiling out SMM support
 
 * Cleanup and documentation of SMM state save area format
 
 * Preserve interrupt shadow in SMM state save area
 
 * Respond to generic signals during slow page faults
 
 * Fixes and optimizations for the non-executable huge page errata fix.
 
 * Reprogram all performance counters on PMU filter change
 
 * Cleanups to Hyper-V emulation and tests
 
 * Process Hyper-V TLB flushes from a nested guest (i.e. from a L2 guest
   running on top of a L1 Hyper-V hypervisor)
 
 * Advertise several new Intel features
 
 * x86 Xen-for-KVM:
 
 ** Allow the Xen runstate information to cross a page boundary
 
 ** Allow XEN_RUNSTATE_UPDATE flag behaviour to be configured
 
 ** Add support for 32-bit guests in SCHEDOP_poll
 
 * Notable x86 fixes and cleanups:
 
 ** One-off fixes for various emulation flows (SGX, VMXON, NRIPS=0).
 
 ** Reinstate IBPB on emulated VM-Exit that was incorrectly dropped a few
    years back when eliminating unnecessary barriers when switching between
    vmcs01 and vmcs02.
 
 ** Clean up vmread_error_trampoline() to make it more obvious that params
    must be passed on the stack, even for x86-64.
 
 ** Let userspace set all supported bits in MSR_IA32_FEAT_CTL irrespective
    of the current guest CPUID.
 
 ** Fudge around a race with TSC refinement that results in KVM incorrectly
    thinking a guest needs TSC scaling when running on a CPU with a
    constant TSC, but no hardware-enumerated TSC frequency.
 
 ** Advertise (on AMD) that the SMM_CTL MSR is not supported
 
 ** Remove unnecessary exports
 
 Generic:
 
 * Support for responding to signals during page faults; introduces
   new FOLL_INTERRUPTIBLE flag that was reviewed by mm folks
 
 Selftests:
 
 * Fix an inverted check in the access tracking perf test, and restore
   support for asserting that there aren't too many idle pages when
   running on bare metal.
 
 * Fix build errors that occur in certain setups (unsure exactly what is
   unique about the problematic setup) due to glibc overriding
   static_assert() to a variant that requires a custom message.
 
 * Introduce actual atomics for clear/set_bit() in selftests
 
 * Add support for pinning vCPUs in dirty_log_perf_test.
 
 * Rename the so called "perf_util" framework to "memstress".
 
 * Add a lightweight psuedo RNG for guest use, and use it to randomize
   the access pattern and write vs. read percentage in the memstress tests.
 
 * Add a common ucall implementation; code dedup and pre-work for running
   SEV (and beyond) guests in selftests.
 
 * Provide a common constructor and arch hook, which will eventually be
   used by x86 to automatically select the right hypercall (AMD vs. Intel).
 
 * A bunch of added/enabled/fixed selftests for ARM64, covering memslots,
   breakpoints, stage-2 faults and access tracking.
 
 * x86-specific selftest changes:
 
 ** Clean up x86's page table management.
 
 ** Clean up and enhance the "smaller maxphyaddr" test, and add a related
    test to cover generic emulation failure.
 
 ** Clean up the nEPT support checks.
 
 ** Add X86_PROPERTY_* framework to retrieve multi-bit CPUID values.
 
 ** Fix an ordering issue in the AMX test introduced by recent conversions
    to use kvm_cpu_has(), and harden the code to guard against similar bugs
    in the future.  Anything that tiggers caching of KVM's supported CPUID,
    kvm_cpu_has() in this case, effectively hides opt-in XSAVE features if
    the caching occurs before the test opts in via prctl().
 
 Documentation:
 
 * Remove deleted ioctls from documentation
 
 * Clean up the docs for the x86 MSR filter.
 
 * Various fixes
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM64:

   - Enable the per-vcpu dirty-ring tracking mechanism, together with an
     option to keep the good old dirty log around for pages that are
     dirtied by something other than a vcpu.

   - Switch to the relaxed parallel fault handling, using RCU to delay
     page table reclaim and giving better performance under load.

   - Relax the MTE ABI, allowing a VMM to use the MAP_SHARED mapping
     option, which multi-process VMMs such as crosvm rely on (see merge
     commit 382b5b87a9: "Fix a number of issues with MTE, such as
     races on the tags being initialised vs the PG_mte_tagged flag as
     well as the lack of support for VM_SHARED when KVM is involved.
     Patches from Catalin Marinas and Peter Collingbourne").

   - Merge the pKVM shadow vcpu state tracking that allows the
     hypervisor to have its own view of a vcpu, keeping that state
     private.

   - Add support for the PMUv3p5 architecture revision, bringing support
     for 64bit counters on systems that support it, and fix the
     no-quite-compliant CHAIN-ed counter support for the machines that
     actually exist out there.

   - Fix a handful of minor issues around 52bit VA/PA support (64kB
     pages only) as a prefix of the oncoming support for 4kB and 16kB
     pages.

   - Pick a small set of documentation and spelling fixes, because no
     good merge window would be complete without those.

  s390:

   - Second batch of the lazy destroy patches

   - First batch of KVM changes for kernel virtual != physical address
     support

   - Removal of a unused function

  x86:

   - Allow compiling out SMM support

   - Cleanup and documentation of SMM state save area format

   - Preserve interrupt shadow in SMM state save area

   - Respond to generic signals during slow page faults

   - Fixes and optimizations for the non-executable huge page errata
     fix.

   - Reprogram all performance counters on PMU filter change

   - Cleanups to Hyper-V emulation and tests

   - Process Hyper-V TLB flushes from a nested guest (i.e. from a L2
     guest running on top of a L1 Hyper-V hypervisor)

   - Advertise several new Intel features

   - x86 Xen-for-KVM:

      - Allow the Xen runstate information to cross a page boundary

      - Allow XEN_RUNSTATE_UPDATE flag behaviour to be configured

      - Add support for 32-bit guests in SCHEDOP_poll

   - Notable x86 fixes and cleanups:

      - One-off fixes for various emulation flows (SGX, VMXON, NRIPS=0).

      - Reinstate IBPB on emulated VM-Exit that was incorrectly dropped
        a few years back when eliminating unnecessary barriers when
        switching between vmcs01 and vmcs02.

      - Clean up vmread_error_trampoline() to make it more obvious that
        params must be passed on the stack, even for x86-64.

      - Let userspace set all supported bits in MSR_IA32_FEAT_CTL
        irrespective of the current guest CPUID.

      - Fudge around a race with TSC refinement that results in KVM
        incorrectly thinking a guest needs TSC scaling when running on a
        CPU with a constant TSC, but no hardware-enumerated TSC
        frequency.

      - Advertise (on AMD) that the SMM_CTL MSR is not supported

      - Remove unnecessary exports

  Generic:

   - Support for responding to signals during page faults; introduces
     new FOLL_INTERRUPTIBLE flag that was reviewed by mm folks

  Selftests:

   - Fix an inverted check in the access tracking perf test, and restore
     support for asserting that there aren't too many idle pages when
     running on bare metal.

   - Fix build errors that occur in certain setups (unsure exactly what
     is unique about the problematic setup) due to glibc overriding
     static_assert() to a variant that requires a custom message.

   - Introduce actual atomics for clear/set_bit() in selftests

   - Add support for pinning vCPUs in dirty_log_perf_test.

   - Rename the so called "perf_util" framework to "memstress".

   - Add a lightweight psuedo RNG for guest use, and use it to randomize
     the access pattern and write vs. read percentage in the memstress
     tests.

   - Add a common ucall implementation; code dedup and pre-work for
     running SEV (and beyond) guests in selftests.

   - Provide a common constructor and arch hook, which will eventually
     be used by x86 to automatically select the right hypercall (AMD vs.
     Intel).

   - A bunch of added/enabled/fixed selftests for ARM64, covering
     memslots, breakpoints, stage-2 faults and access tracking.

   - x86-specific selftest changes:

      - Clean up x86's page table management.

      - Clean up and enhance the "smaller maxphyaddr" test, and add a
        related test to cover generic emulation failure.

      - Clean up the nEPT support checks.

      - Add X86_PROPERTY_* framework to retrieve multi-bit CPUID values.

      - Fix an ordering issue in the AMX test introduced by recent
        conversions to use kvm_cpu_has(), and harden the code to guard
        against similar bugs in the future. Anything that tiggers
        caching of KVM's supported CPUID, kvm_cpu_has() in this case,
        effectively hides opt-in XSAVE features if the caching occurs
        before the test opts in via prctl().

  Documentation:

   - Remove deleted ioctls from documentation

   - Clean up the docs for the x86 MSR filter.

   - Various fixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (361 commits)
  KVM: x86: Add proper ReST tables for userspace MSR exits/flags
  KVM: selftests: Allocate ucall pool from MEM_REGION_DATA
  KVM: arm64: selftests: Align VA space allocator with TTBR0
  KVM: arm64: Fix benign bug with incorrect use of VA_BITS
  KVM: arm64: PMU: Fix period computation for 64bit counters with 32bit overflow
  KVM: x86: Advertise that the SMM_CTL MSR is not supported
  KVM: x86: remove unnecessary exports
  KVM: selftests: Fix spelling mistake "probabalistic" -> "probabilistic"
  tools: KVM: selftests: Convert clear/set_bit() to actual atomics
  tools: Drop "atomic_" prefix from atomic test_and_set_bit()
  tools: Drop conflicting non-atomic test_and_{clear,set}_bit() helpers
  KVM: selftests: Use non-atomic clear/set bit helpers in KVM tests
  perf tools: Use dedicated non-atomic clear/set bit helpers
  tools: Take @bit as an "unsigned long" in {clear,set}_bit() helpers
  KVM: arm64: selftests: Enable single-step without a "full" ucall()
  KVM: x86: fix APICv/x2AVIC disabled when vm reboot by itself
  KVM: Remove stale comment about KVM_REQ_UNHALT
  KVM: Add missing arch for KVM_CREATE_DEVICE and KVM_{SET,GET}_DEVICE_ATTR
  KVM: Reference to kvm_userspace_memory_region in doc and comments
  KVM: Delete all references to removed KVM_SET_MEMORY_ALIAS ioctl
  ...
 2022-12-15 11:12:21 -08:00
Linus Torvalds
e2ca6ba6ba MM patches for 6.2-rc1. 
- More userfaultfs work from Peter Xu.
 
 - Several convert-to-folios series from Sidhartha Kumar and Huang Ying.
 
 - Some filemap cleanups from Vishal Moola.
 
 - David Hildenbrand added the ability to selftest anon memory COW handling.
 
 - Some cpuset simplifications from Liu Shixin.
 
 - Addition of vmalloc tracing support by Uladzislau Rezki.
 
 - Some pagecache folioifications and simplifications from Matthew Wilcox.
 
 - A pagemap cleanup from Kefeng Wang: we have VM_ACCESS_FLAGS, so use it.
 
 - Miguel Ojeda contributed some cleanups for our use of the
   __no_sanitize_thread__ gcc keyword.  This series shold have been in the
   non-MM tree, my bad.
 
 - Naoya Horiguchi improved the interaction between memory poisoning and
   memory section removal for huge pages.
 
 - DAMON cleanups and tuneups from SeongJae Park
 
 - Tony Luck fixed the handling of COW faults against poisoned pages.
 
 - Peter Xu utilized the PTE marker code for handling swapin errors.
 
 - Hugh Dickins reworked compound page mapcount handling, simplifying it
   and making it more efficient.
 
 - Removal of the autonuma savedwrite infrastructure from Nadav Amit and
   David Hildenbrand.
 
 - zram support for multiple compression streams from Sergey Senozhatsky.
 
 - David Hildenbrand reworked the GUP code's R/O long-term pinning so
   that drivers no longer need to use the FOLL_FORCE workaround which
   didn't work very well anyway.
 
 - Mel Gorman altered the page allocator so that local IRQs can remnain
   enabled during per-cpu page allocations.
 
 - Vishal Moola removed the try_to_release_page() wrapper.
 
 - Stefan Roesch added some per-BDI sysfs tunables which are used to
   prevent network block devices from dirtying excessive amounts of
   pagecache.
 
 - David Hildenbrand did some cleanup and repair work on KSM COW
   breaking.
 
 - Nhat Pham and Johannes Weiner have implemented writeback in zswap's
   zsmalloc backend.
 
 - Brian Foster has fixed a longstanding corner-case oddity in
   file[map]_write_and_wait_range().
 
 - sparse-vmemmap changes for MIPS, LoongArch and NIOS2 from Feiyang
   Chen.
 
 - Shiyang Ruan has done some work on fsdax, to make its reflink mode
   work better under xfstests.  Better, but still not perfect.
 
 - Christoph Hellwig has removed the .writepage() method from several
   filesystems.  They only need .writepages().
 
 - Yosry Ahmed wrote a series which fixes the memcg reclaim target
   beancounting.
 
 - David Hildenbrand has fixed some of our MM selftests for 32-bit
   machines.
 
 - Many singleton patches, as usual.
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Merge tag 'mm-stable-2022-12-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - More userfaultfs work from Peter Xu

 - Several convert-to-folios series from Sidhartha Kumar and Huang Ying

 - Some filemap cleanups from Vishal Moola

 - David Hildenbrand added the ability to selftest anon memory COW
   handling

 - Some cpuset simplifications from Liu Shixin

 - Addition of vmalloc tracing support by Uladzislau Rezki

 - Some pagecache folioifications and simplifications from Matthew
   Wilcox

 - A pagemap cleanup from Kefeng Wang: we have VM_ACCESS_FLAGS, so use
   it

 - Miguel Ojeda contributed some cleanups for our use of the
   __no_sanitize_thread__ gcc keyword.

   This series should have been in the non-MM tree, my bad

 - Naoya Horiguchi improved the interaction between memory poisoning and
   memory section removal for huge pages

 - DAMON cleanups and tuneups from SeongJae Park

 - Tony Luck fixed the handling of COW faults against poisoned pages

 - Peter Xu utilized the PTE marker code for handling swapin errors

 - Hugh Dickins reworked compound page mapcount handling, simplifying it
   and making it more efficient

 - Removal of the autonuma savedwrite infrastructure from Nadav Amit and
   David Hildenbrand

 - zram support for multiple compression streams from Sergey Senozhatsky

 - David Hildenbrand reworked the GUP code's R/O long-term pinning so
   that drivers no longer need to use the FOLL_FORCE workaround which
   didn't work very well anyway

 - Mel Gorman altered the page allocator so that local IRQs can remnain
   enabled during per-cpu page allocations

 - Vishal Moola removed the try_to_release_page() wrapper

 - Stefan Roesch added some per-BDI sysfs tunables which are used to
   prevent network block devices from dirtying excessive amounts of
   pagecache

 - David Hildenbrand did some cleanup and repair work on KSM COW
   breaking

 - Nhat Pham and Johannes Weiner have implemented writeback in zswap's
   zsmalloc backend

 - Brian Foster has fixed a longstanding corner-case oddity in
   file[map]_write_and_wait_range()

 - sparse-vmemmap changes for MIPS, LoongArch and NIOS2 from Feiyang
   Chen

 - Shiyang Ruan has done some work on fsdax, to make its reflink mode
   work better under xfstests. Better, but still not perfect

 - Christoph Hellwig has removed the .writepage() method from several
   filesystems. They only need .writepages()

 - Yosry Ahmed wrote a series which fixes the memcg reclaim target
   beancounting

 - David Hildenbrand has fixed some of our MM selftests for 32-bit
   machines

 - Many singleton patches, as usual

* tag 'mm-stable-2022-12-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (313 commits)
  mm/hugetlb: set head flag before setting compound_order in __prep_compound_gigantic_folio
  mm: mmu_gather: allow more than one batch of delayed rmaps
  mm: fix typo in struct pglist_data code comment
  kmsan: fix memcpy tests
  mm: add cond_resched() in swapin_walk_pmd_entry()
  mm: do not show fs mm pc for VM_LOCKONFAULT pages
  selftests/vm: ksm_functional_tests: fixes for 32bit
  selftests/vm: cow: fix compile warning on 32bit
  selftests/vm: madv_populate: fix missing MADV_POPULATE_(READ|WRITE) definitions
  mm/gup_test: fix PIN_LONGTERM_TEST_READ with highmem
  mm,thp,rmap: fix races between updates of subpages_mapcount
  mm: memcg: fix swapcached stat accounting
  mm: add nodes= arg to memory.reclaim
  mm: disable top-tier fallback to reclaim on proactive reclaim
  selftests: cgroup: make sure reclaim target memcg is unprotected
  selftests: cgroup: refactor proactive reclaim code to reclaim_until()
  mm: memcg: fix stale protection of reclaim target memcg
  mm/mmap: properly unaccount memory on mas_preallocate() failure
  omfs: remove ->writepage
  jfs: remove ->writepage
  ...
 2022-12-13 19:29:45 -08:00
Linus Torvalds
ce8a79d560 for-6.2/block-2022-12-08 
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Merge tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux

Pull block updates from Jens Axboe:

 - NVMe pull requests via Christoph:
      - Support some passthrough commands without CAP_SYS_ADMIN (Kanchan
        Joshi)
      - Refactor PCIe probing and reset (Christoph Hellwig)
      - Various fabrics authentication fixes and improvements (Sagi
        Grimberg)
      - Avoid fallback to sequential scan due to transient issues (Uday
        Shankar)
      - Implement support for the DEAC bit in Write Zeroes (Christoph
        Hellwig)
      - Allow overriding the IEEE OUI and firmware revision in configfs
        for nvmet (Aleksandr Miloserdov)
      - Force reconnect when number of queue changes in nvmet (Daniel
        Wagner)
      - Minor fixes and improvements (Uros Bizjak, Joel Granados, Sagi
        Grimberg, Christoph Hellwig, Christophe JAILLET)
      - Fix and cleanup nvme-fc req allocation (Chaitanya Kulkarni)
      - Use the common tagset helpers in nvme-pci driver (Christoph
        Hellwig)
      - Cleanup the nvme-pci removal path (Christoph Hellwig)
      - Use kstrtobool() instead of strtobool (Christophe JAILLET)
      - Allow unprivileged passthrough of Identify Controller (Joel
        Granados)
      - Support io stats on the mpath device (Sagi Grimberg)
      - Minor nvmet cleanup (Sagi Grimberg)

 - MD pull requests via Song:
      - Code cleanups (Christoph)
      - Various fixes

 - Floppy pull request from Denis:
      - Fix a memory leak in the init error path (Yuan)

 - Series fixing some batch wakeup issues with sbitmap (Gabriel)

 - Removal of the pktcdvd driver that was deprecated more than 5 years
   ago, and subsequent removal of the devnode callback in struct
   block_device_operations as no users are now left (Greg)

 - Fix for partition read on an exclusively opened bdev (Jan)

 - Series of elevator API cleanups (Jinlong, Christoph)

 - Series of fixes and cleanups for blk-iocost (Kemeng)

 - Series of fixes and cleanups for blk-throttle (Kemeng)

 - Series adding concurrent support for sync queues in BFQ (Yu)

 - Series bringing drbd a bit closer to the out-of-tree maintained
   version (Christian, Joel, Lars, Philipp)

 - Misc drbd fixes (Wang)

 - blk-wbt fixes and tweaks for enable/disable (Yu)

 - Fixes for mq-deadline for zoned devices (Damien)

 - Add support for read-only and offline zones for null_blk
   (Shin'ichiro)

 - Series fixing the delayed holder tracking, as used by DM (Yu,
   Christoph)

 - Series enabling bio alloc caching for IRQ based IO (Pavel)

 - Series enabling userspace peer-to-peer DMA (Logan)

 - BFQ waker fixes (Khazhismel)

 - Series fixing elevator refcount issues (Christoph, Jinlong)

 - Series cleaning up references around queue destruction (Christoph)

 - Series doing quiesce by tagset, enabling cleanups in drivers
   (Christoph, Chao)

 - Series untangling the queue kobject and queue references (Christoph)

 - Misc fixes and cleanups (Bart, David, Dawei, Jinlong, Kemeng, Ye,
   Yang, Waiman, Shin'ichiro, Randy, Pankaj, Christoph)

* tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux: (247 commits)
  blktrace: Fix output non-blktrace event when blk_classic option enabled
  block: sed-opal: Don't include <linux/kernel.h>
  sed-opal: allow using IOC_OPAL_SAVE for locking too
  blk-cgroup: Fix typo in comment
  block: remove bio_set_op_attrs
  nvmet: don't open-code NVME_NS_ATTR_RO enumeration
  nvme-pci: use the tagset alloc/free helpers
  nvme: add the Apple shared tag workaround to nvme_alloc_io_tag_set
  nvme: only set reserved_tags in nvme_alloc_io_tag_set for fabrics controllers
  nvme: consolidate setting the tagset flags
  nvme: pass nr_maps explicitly to nvme_alloc_io_tag_set
  block: bio_copy_data_iter
  nvme-pci: split out a nvme_pci_ctrl_is_dead helper
  nvme-pci: return early on ctrl state mismatch in nvme_reset_work
  nvme-pci: rename nvme_disable_io_queues
  nvme-pci: cleanup nvme_suspend_queue
  nvme-pci: remove nvme_pci_disable
  nvme-pci: remove nvme_disable_admin_queue
  nvme: merge nvme_shutdown_ctrl into nvme_disable_ctrl
  nvme: use nvme_wait_ready in nvme_shutdown_ctrl
  ...
 2022-12-13 10:43:59 -08:00
Sidhartha Kumar
c45bc55a99 mm/hugetlb: set head flag before setting compound_order in __prep_compound_gigantic_folio 
folio_set_compound_order() checks if the passed in folio is a large folio.
A large folio is indicated by the PG_head flag.  Call __folio_set_head()
before setting the order.

Link: https://lkml.kernel.org/r/20221212225529.22493-1-sidhartha.kumar@oracle.com
Fixes: d1c6095572 ("mm/hugetlb: convert hugetlb prep functions to folios")
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reported-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-12-12 16:47:11 -08:00
Sidhartha Kumar
19fc1a7e8b mm/hugetlb: change hugetlb allocation functions to return a folio 
Many hugetlb allocation helper functions have now been converting to
folios, update their higher level callers to be compatible with folios. 
alloc_pool_huge_page is reorganized to avoid a smatch warning reporting
the folio variable is uninitialized.

[sidhartha.kumar@oracle.com: update alloc_and_dissolve_hugetlb_folio comments]
  Link: https://lkml.kernel.org/r/20221206233512.146535-1-sidhartha.kumar@oracle.com
Link: https://lkml.kernel.org/r/20221129225039.82257-11-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reported-by: Wei Chen <harperchen1110@gmail.com>
Suggested-by: John Hubbard <jhubbard@nvidia.com>
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Tarun Sahu <tsahu@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-12-11 18:12:15 -08:00
Sidhartha Kumar
d1c6095572 mm/hugetlb: convert hugetlb prep functions to folios 
Convert prep_new_huge_page() and __prep_compound_gigantic_page() to
folios.

Link: https://lkml.kernel.org/r/20221129225039.82257-10-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tarun Sahu <tsahu@linux.ibm.com>
Cc: Wei Chen <harperchen1110@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-12-11 18:12:15 -08:00
Sidhartha Kumar
7f325a8d25 mm/hugetlb: convert free_gigantic_page() to folios 
Convert callers of free_gigantic_page() to use folios, function is then
renamed to free_gigantic_folio().

Link: https://lkml.kernel.org/r/20221129225039.82257-9-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tarun Sahu <tsahu@linux.ibm.com>
Cc: Wei Chen <harperchen1110@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-12-11 18:12:14 -08:00
Sidhartha Kumar
240d67a86e mm/hugetlb: convert enqueue_huge_page() to folios 
Convert callers of enqueue_huge_page() to pass in a folio, function is
renamed to enqueue_hugetlb_folio().

Link: https://lkml.kernel.org/r/20221129225039.82257-8-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tarun Sahu <tsahu@linux.ibm.com>
Cc: Wei Chen <harperchen1110@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-12-11 18:12:14 -08:00
Sidhartha Kumar
2f6c57d696 mm/hugetlb: convert add_hugetlb_page() to folios and add hugetlb_cma_folio() 
Convert add_hugetlb_page() to take in a folio, also convert
hugetlb_cma_page() to take in a folio.

Link: https://lkml.kernel.org/r/20221129225039.82257-7-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tarun Sahu <tsahu@linux.ibm.com>
Cc: Wei Chen <harperchen1110@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-12-11 18:12:14 -08:00
Sidhartha Kumar
d6ef19e25d mm/hugetlb: convert update_and_free_page() to folios 
Make more progress on converting the free_huge_page() destructor to
operate on folios by converting update_and_free_page() to folios.

Link: https://lkml.kernel.org/r/20221129225039.82257-6-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>\
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tarun Sahu <tsahu@linux.ibm.com>
Cc: Wei Chen <harperchen1110@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-12-11 18:12:14 -08:00
Sidhartha Kumar
cfd5082b51 mm/hugetlb: convert remove_hugetlb_page() to folios 
Removes page_folio() call by converting callers to directly pass a folio
into __remove_hugetlb_page().

Link: https://lkml.kernel.org/r/20221129225039.82257-5-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tarun Sahu <tsahu@linux.ibm.com>
Cc: Wei Chen <harperchen1110@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-12-11 18:12:14 -08:00
Sidhartha Kumar
1a7cdab59b mm/hugetlb: convert dissolve_free_huge_page() to folios 
Removes compound_head() call by using a folio rather than a head page.

Link: https://lkml.kernel.org/r/20221129225039.82257-4-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tarun Sahu <tsahu@linux.ibm.com>
Cc: Wei Chen <harperchen1110@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-12-11 18:12:14 -08:00
Sidhartha Kumar
911565b828 mm/hugetlb: convert destroy_compound_gigantic_page() to folios 
Convert page operations within __destroy_compound_gigantic_page() to the
corresponding folio operations.

Link: https://lkml.kernel.org/r/20221129225039.82257-3-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tarun Sahu <tsahu@linux.ibm.com>
Cc: Wei Chen <harperchen1110@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-12-11 18:12:13 -08:00
Sidhartha Kumar
9fd330582b mm: add folio dtor and order setter functions 
Patch series "convert core hugetlb functions to folios", v5.

============== OVERVIEW ===========================
Now that many hugetlb helper functions that deal with hugetlb specific
flags[1] and hugetlb cgroups[2] are converted to folios, higher level
allocation, prep, and freeing functions within hugetlb can also be
converted to operate in folios.

Patch 1 of this series implements the wrapper functions around setting the
compound destructor and compound order for a folio.  Besides the user
added in patch 1, patch 2 and patch 9 also use these helper functions.

Patches 2-10 convert the higher level hugetlb functions to folios.

============== TESTING ===========================
LTP:
	Ran 10 back to back rounds of the LTP hugetlb test suite.

Gigantic Huge Pages:
	Test allocation and freeing via hugeadm commands:
		hugeadm --pool-pages-min 1GB:10
		hugeadm --pool-pages-min 1GB:0

Demote:
	Demote 1 1GB hugepages to 512 2MB hugepages
		echo 1 > /sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages
		echo 1 > /sys/kernel/mm/hugepages/hugepages-1048576kB/demote
		cat /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
			# 512
		cat /sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages
			# 0

[1] https://lore.kernel.org/lkml/20220922154207.1575343-1-sidhartha.kumar@oracle.com/
[2] https://lore.kernel.org/linux-mm/20221101223059.460937-1-sidhartha.kumar@oracle.com/


This patch (of 10):

Add folio equivalents for set_compound_order() and
set_compound_page_dtor().

Also remove extra new-lines introduced by mm/hugetlb: convert
move_hugetlb_state() to folios and mm/hugetlb_cgroup: convert
hugetlb_cgroup_uncharge_page() to folios.

[sidhartha.kumar@oracle.com: clarify folio_set_compound_order() zero support]
  Link: https://lkml.kernel.org/r/20221207223731.32784-1-sidhartha.kumar@oracle.com
Link: https://lkml.kernel.org/r/20221129225039.82257-1-sidhartha.kumar@oracle.com
Link: https://lkml.kernel.org/r/20221129225039.82257-2-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Suggested-by: Mike Kravetz <mike.kravetz@oracle.com>
Suggested-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Tarun Sahu <tsahu@linux.ibm.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Wei Chen <harperchen1110@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-12-11 18:12:13 -08:00
David Hildenbrand
84209e87c6 mm/gup: reliable R/O long-term pinning in COW mappings 
We already support reliable R/O pinning of anonymous memory. However,
assume we end up pinning (R/O long-term) a pagecache page or the shared
zeropage inside a writable private ("COW") mapping. The next write access
will trigger a write-fault and replace the pinned page by an exclusive
anonymous page in the process page tables to break COW: the pinned page no
longer corresponds to the page mapped into the process' page table.

Now that FAULT_FLAG_UNSHARE can break COW on anything mapped into a
COW mapping, let's properly break COW first before R/O long-term
pinning something that's not an exclusive anon page inside a COW
mapping. FAULT_FLAG_UNSHARE will break COW and map an exclusive anon page
instead that can get pinned safely.

With this change, we can stop using FOLL_FORCE|FOLL_WRITE for reliable
R/O long-term pinning in COW mappings.

With this change, the new R/O long-term pinning tests for non-anonymous
memory succeed:
  # [RUN] R/O longterm GUP pin ... with shared zeropage
  ok 151 Longterm R/O pin is reliable
  # [RUN] R/O longterm GUP pin ... with memfd
  ok 152 Longterm R/O pin is reliable
  # [RUN] R/O longterm GUP pin ... with tmpfile
  ok 153 Longterm R/O pin is reliable
  # [RUN] R/O longterm GUP pin ... with huge zeropage
  ok 154 Longterm R/O pin is reliable
  # [RUN] R/O longterm GUP pin ... with memfd hugetlb (2048 kB)
  ok 155 Longterm R/O pin is reliable
  # [RUN] R/O longterm GUP pin ... with memfd hugetlb (1048576 kB)
  ok 156 Longterm R/O pin is reliable
  # [RUN] R/O longterm GUP-fast pin ... with shared zeropage
  ok 157 Longterm R/O pin is reliable
  # [RUN] R/O longterm GUP-fast pin ... with memfd
  ok 158 Longterm R/O pin is reliable
  # [RUN] R/O longterm GUP-fast pin ... with tmpfile
  ok 159 Longterm R/O pin is reliable
  # [RUN] R/O longterm GUP-fast pin ... with huge zeropage
  ok 160 Longterm R/O pin is reliable
  # [RUN] R/O longterm GUP-fast pin ... with memfd hugetlb (2048 kB)
  ok 161 Longterm R/O pin is reliable
  # [RUN] R/O longterm GUP-fast pin ... with memfd hugetlb (1048576 kB)
  ok 162 Longterm R/O pin is reliable

Note 1: We don't care about short-term R/O-pinning, because they have
snapshot semantics: they are not supposed to observe modifications that
happen after pinning.

As one example, assume we start direct I/O to read from a page and store
page content into a file: modifications to page content after starting
direct I/O are not guaranteed to end up in the file. So even if we'd pin
the shared zeropage, the end result would be as expected -- getting zeroes
stored to the file.

Note 2: For shared mappings we'll now always fallback to the slow path to
lookup the VMA when R/O long-term pining. While that's the necessary price
we have to pay right now, it's actually not that bad in practice: most
FOLL_LONGTERM users already specify FOLL_WRITE, for example, along with
FOLL_FORCE because they tried dealing with COW mappings correctly ...

Note 3: For users that use FOLL_LONGTERM right now without FOLL_WRITE,
such as VFIO, we'd now no longer pin the shared zeropage. Instead, we'd
populate exclusive anon pages that we can pin. There was a concern that
this could affect the memlock limit of existing setups.

For example, a VM running with VFIO could run into the memlock limit and
fail to run. However, we essentially had the same behavior already in
commit 17839856fd ("gup: document and work around "COW can break either
way" issue") which got merged into some enterprise distros, and there were
not any such complaints. So most probably, we're fine.

Link: https://lkml.kernel.org/r/20221116102659.70287-10-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-30 15:58:58 -08:00
David Hildenbrand
cdc5021cda mm: add early FAULT_FLAG_UNSHARE consistency checks 
For now, FAULT_FLAG_UNSHARE only applies to anonymous pages, which
implies a COW mapping. Let's hide FAULT_FLAG_UNSHARE early if we're not
dealing with a COW mapping, such that we treat it like a read fault as
documented and don't have to worry about the flag throughout all fault
handlers.

While at it, centralize the check for mutual exclusion of
FAULT_FLAG_UNSHARE and FAULT_FLAG_WRITE and just drop the check that
either flag is set in the WP handler.

Link: https://lkml.kernel.org/r/20221116102659.70287-5-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-30 15:58:57 -08:00
Mike Kravetz
369258ce41 hugetlb: remove duplicate mmu notifications 
The common hugetlb unmap routine __unmap_hugepage_range performs mmu
notification calls.  However, in the case where __unmap_hugepage_range is
called via __unmap_hugepage_range_final, mmu notification calls are
performed earlier in other calling routines.

Remove mmu notification calls from __unmap_hugepage_range.  Add
notification calls to the only other caller: unmap_hugepage_range. 
unmap_hugepage_range is called for truncation and hole punch, so change
notification type from UNMAP to CLEAR as this is more appropriate.

Link: https://lkml.kernel.org/r/20221114235507.294320-4-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Suggested-by: Peter Xu <peterx@redhat.com>
Cc: Wei Chen <harperchen1110@gmail.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Rik van Riel <riel@surriel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-30 15:58:55 -08:00
Hugh Dickins
cb67f4282b mm,thp,rmap: simplify compound page mapcount handling 
Compound page (folio) mapcount calculations have been different for anon
and file (or shmem) THPs, and involved the obscure PageDoubleMap flag. 
And each huge mapping and unmapping of a file (or shmem) THP involved
atomically incrementing and decrementing the mapcount of every subpage of
that huge page, dirtying many struct page cachelines.

Add subpages_mapcount field to the struct folio and first tail page, so
that the total of subpage mapcounts is available in one place near the
head: then page_mapcount() and total_mapcount() and page_mapped(), and
their folio equivalents, are so quick that anon and file and hugetlb don't
need to be optimized differently.  Delete the unloved PageDoubleMap.

page_add and page_remove rmap functions must now maintain the
subpages_mapcount as well as the subpage _mapcount, when dealing with pte
mappings of huge pages; and correct maintenance of NR_ANON_MAPPED and
NR_FILE_MAPPED statistics still needs reading through the subpages, using
nr_subpages_unmapped() - but only when first or last pmd mapping finds
subpages_mapcount raised (double-map case, not the common case).

But are those counts (used to decide when to split an anon THP, and in
vmscan's pagecache_reclaimable heuristic) correctly maintained?  Not
quite: since page_remove_rmap() (and also split_huge_pmd()) is often
called without page lock, there can be races when a subpage pte mapcount
0<->1 while compound pmd mapcount 0<->1 is scanning - races which the
previous implementation had prevented.  The statistics might become
inaccurate, and even drift down until they underflow through 0.  That is
not good enough, but is better dealt with in a followup patch.

Update a few comments on first and second tail page overlaid fields. 
hugepage_add_new_anon_rmap() has to "increment" compound_mapcount, but
subpages_mapcount and compound_pincount are already correctly at 0, so
delete its reinitialization of compound_pincount.

A simple 100 X munmap(mmap(2GB, MAP_SHARED|MAP_POPULATE, tmpfs), 2GB) took
18 seconds on small pages, and used to take 1 second on huge pages, but
now takes 119 milliseconds on huge pages.  Mapping by pmds a second time
used to take 860ms and now takes 92ms; mapping by pmds after mapping by
ptes (when the scan is needed) used to take 870ms and now takes 495ms. 
But there might be some benchmarks which would show a slowdown, because
tail struct pages now fall out of cache until final freeing checks them.

Link: https://lkml.kernel.org/r/47ad693-717-79c8-e1ba-46c3a6602e48@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: James Houghton <jthoughton@google.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-30 15:58:46 -08:00
Sidhartha Kumar
345c62d163 mm/hugetlb: convert move_hugetlb_state() to folios 
Clean up unmap_and_move_huge_page() by converting move_hugetlb_state() to
take in folios.

[akpm@linux-foundation.org: fix CONFIG_HUGETLB_PAGE=n build]
Link: https://lkml.kernel.org/r/20221101223059.460937-10-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Bui Quang Minh <minhquangbui99@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-30 15:58:43 -08:00
Sidhartha Kumar
d4ab0316cc mm/hugetlb_cgroup: convert hugetlb_cgroup_uncharge_page() to folios 
Continue to use a folio inside free_huge_page() by converting
hugetlb_cgroup_uncharge_page*() to folios.

Link: https://lkml.kernel.org/r/20221101223059.460937-8-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Bui Quang Minh <minhquangbui99@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-30 15:58:43 -08:00
Sidhartha Kumar
0356c4b96f mm/hugetlb: convert free_huge_page to folios 
Use folios inside free_huge_page(), this is in preparation for converting
hugetlb_cgroup_uncharge_page() to take in a folio.

Link: https://lkml.kernel.org/r/20221101223059.460937-7-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Bui Quang Minh <minhquangbui99@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-30 15:58:43 -08:00
Sidhartha Kumar
d5e33bd8c1 mm/hugetlb: convert isolate_or_dissolve_huge_page to folios 
Removes a call to compound_head() by using a folio when operating on the
head page of a hugetlb compound page.

Link: https://lkml.kernel.org/r/20221101223059.460937-6-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Bui Quang Minh <minhquangbui99@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-30 15:58:42 -08:00
Sidhartha Kumar
29f394304f mm/hugetlb_cgroup: convert hugetlb_cgroup_migrate to folios 
Cleans up intermediate page to folio conversion code in
hugetlb_cgroup_migrate() by changing its arguments from pages to folios.

Link: https://lkml.kernel.org/r/20221101223059.460937-5-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Bui Quang Minh <minhquangbui99@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-30 15:58:42 -08:00
Sidhartha Kumar
de656ed376 mm/hugetlb_cgroup: convert set_hugetlb_cgroup*() to folios 
Allows __prep_new_huge_page() to operate on a folio by converting
set_hugetlb_cgroup*() to take in a folio.

Link: https://lkml.kernel.org/r/20221101223059.460937-4-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Bui Quang Minh <minhquangbui99@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-30 15:58:42 -08:00
Sidhartha Kumar
f074732d59 mm/hugetlb_cgroup: convert hugetlb_cgroup_from_page() to folios 
Introduce folios in __remove_hugetlb_page() by converting
hugetlb_cgroup_from_page() to use folios.

Also gets rid of unsed hugetlb_cgroup_from_page_resv() function.

Link: https://lkml.kernel.org/r/20221101223059.460937-3-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Bui Quang Minh <minhquangbui99@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mina Almasry <almasrymina@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-30 15:58:42 -08:00
Andrew Morton
a38358c934 Merge branch 'mm-hotfixes-stable' into mm-stable 2022-11-30 14:58:42 -08:00
Mike Kravetz
04ada095dc hugetlb: don't delete vma_lock in hugetlb MADV_DONTNEED processing 
madvise(MADV_DONTNEED) ends up calling zap_page_range() to clear page
tables associated with the address range.  For hugetlb vmas,
zap_page_range will call __unmap_hugepage_range_final.  However,
__unmap_hugepage_range_final assumes the passed vma is about to be removed
and deletes the vma_lock to prevent pmd sharing as the vma is on the way
out.  In the case of madvise(MADV_DONTNEED) the vma remains, but the
missing vma_lock prevents pmd sharing and could potentially lead to issues
with truncation/fault races.

This issue was originally reported here [1] as a BUG triggered in
page_try_dup_anon_rmap.  Prior to the introduction of the hugetlb
vma_lock, __unmap_hugepage_range_final cleared the VM_MAYSHARE flag to
prevent pmd sharing.  Subsequent faults on this vma were confused as
VM_MAYSHARE indicates a sharable vma, but was not set so page_mapping was
not set in new pages added to the page table.  This resulted in pages that
appeared anonymous in a VM_SHARED vma and triggered the BUG.

Address issue by adding a new zap flag ZAP_FLAG_UNMAP to indicate an unmap
call from unmap_vmas().  This is used to indicate the 'final' unmapping of
a hugetlb vma.  When called via MADV_DONTNEED, this flag is not set and
the vm_lock is not deleted.

[1] https://lore.kernel.org/lkml/CAO4mrfdLMXsao9RF4fUE8-Wfde8xmjsKrTNMNC9wjUb6JudD0g@mail.gmail.com/

Link: https://lkml.kernel.org/r/20221114235507.294320-3-mike.kravetz@oracle.com
Fixes: 90e7e7f5ef ("mm: enable MADV_DONTNEED for hugetlb mappings")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Wei Chen <harperchen1110@gmail.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-30 14:49:40 -08:00
Mike Kravetz
7fb0728a9b hugetlb: fix __prep_compound_gigantic_page page flag setting 
Commit 2b21624fc2 ("hugetlb: freeze allocated pages before creating
hugetlb pages") changed the order page flags were cleared and set in the
head page.  It moved the __ClearPageReserved after __SetPageHead. 
However, there is a check to make sure __ClearPageReserved is never done
on a head page.  If CONFIG_DEBUG_VM_PGFLAGS is enabled, the following BUG
will be hit when creating a hugetlb gigantic page:

    page dumped because: VM_BUG_ON_PAGE(1 && PageCompound(page))
    ------------[ cut here ]------------
    kernel BUG at include/linux/page-flags.h:500!
    Call Trace will differ depending on whether hugetlb page is created
    at boot time or run time.

Make sure to __ClearPageReserved BEFORE __SetPageHead.

Link: https://lkml.kernel.org/r/20221118195249.178319-1-mike.kravetz@oracle.com
Fixes: 2b21624fc2 ("hugetlb: freeze allocated pages before creating hugetlb pages")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Tested-by: Tarun Sahu <tsahu@linux.ibm.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-22 18:50:44 -08:00
Logan Gunthorpe
4003f107fa mm: introduce FOLL_PCI_P2PDMA to gate getting PCI P2PDMA pages 
GUP Callers that expect PCI P2PDMA pages can now set FOLL_PCI_P2PDMA to
allow obtaining P2PDMA pages. If GUP is called without the flag and a
P2PDMA page is found, it will return an error in try_grab_page() or
try_grab_folio().

The check is safe to do before taking the reference to the page in both
cases seeing the page should be protected by either the appropriate
ptl or mmap_lock; or the gup fast guarantees preventing TLB flushes.

try_grab_folio() has one call site that WARNs on failure and cannot
actually deal with the failure of this function (it seems it will
get into an infinite loop). Expand the comment there to document a
couple more conditions on why it will not fail.

FOLL_PCI_P2PDMA cannot be set if FOLL_LONGTERM is set. This is to copy
fsdax until pgmap refcounts are fixed (see the link below for more
information).

Link: https://lkml.kernel.org/r/Yy4Ot5MoOhsgYLTQ@ziepe.ca
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-3-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
 2022-11-09 11:29:20 -07:00
Logan Gunthorpe
0f0892356f mm: allow multiple error returns in try_grab_page() 
In order to add checks for P2PDMA memory into try_grab_page(), expand
the error return from a bool to an int/error code. Update all the
callsites handle change in usage.

Also remove the WARN_ON_ONCE() call at the callsites seeing there
already is a WARN_ON_ONCE() inside the function if it fails.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221021174116.7200-2-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
 2022-11-09 11:29:20 -07:00
Peter Xu
93c5c61d9e mm/gup: Add FOLL_INTERRUPTIBLE 
We have had FAULT_FLAG_INTERRUPTIBLE but it was never applied to GUPs.  One
issue with it is that not all GUP paths are able to handle signal delivers
besides SIGKILL.

That's not ideal for the GUP users who are actually able to handle these
cases, like KVM.

KVM uses GUP extensively on faulting guest pages, during which we've got
existing infrastructures to retry a page fault at a later time.  Allowing
the GUP to be interrupted by generic signals can make KVM related threads
to be more responsive.  For examples:

  (1) SIGUSR1: which QEMU/KVM uses to deliver an inter-process IPI,
      e.g. when the admin issues a vm_stop QMP command, SIGUSR1 can be
      generated to kick the vcpus out of kernel context immediately,

  (2) SIGINT: which can be used with interactive hypervisor users to stop a
      virtual machine with Ctrl-C without any delays/hangs,

  (3) SIGTRAP: which grants GDB capability even during page faults that are
      stuck for a long time.

Normally hypervisor will be able to receive these signals properly, but not
if we're stuck in a GUP for a long time for whatever reason.  It happens
easily with a stucked postcopy migration when e.g. a network temp failure
happens, then some vcpu threads can hang death waiting for the pages.  With
the new FOLL_INTERRUPTIBLE, we can allow GUP users like KVM to selectively
enable the ability to trap these signals.

Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20221011195809.557016-2-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
 2022-11-09 12:31:26 -05:00
Naoya Horiguchi
e591ef7d96 mm,hwpoison,hugetlb,memory_hotplug: hotremove memory section with hwpoisoned hugepage 
Patch series "mm, hwpoison: improve handling workload related to hugetlb
and memory_hotplug", v7.

This patchset tries to solve the issue among memory_hotplug, hugetlb and hwpoison.
In this patchset, memory hotplug handles hwpoison pages like below:

  - hwpoison pages should not prevent memory hotremove,
  - memory block with hwpoison pages should not be onlined.


This patch (of 4):

HWPoisoned page is not supposed to be accessed once marked, but currently
such accesses can happen during memory hotremove because
do_migrate_range() can be called before dissolve_free_huge_pages() is
called.

Clear HPageMigratable for hwpoisoned hugepages to prevent them from being
migrated.  This should be done in hugetlb_lock to avoid race against
isolate_hugetlb().

get_hwpoison_huge_page() needs to have a flag to show it's called from
unpoison to take refcount of hwpoisoned hugepages, so add it.

[naoya.horiguchi@linux.dev: remove TestClearHPageMigratable and reduce to test and clear separately]
  Link: https://lkml.kernel.org/r/20221025053559.GA2104800@ik1-406-35019.vs.sakura.ne.jp
Link: https://lkml.kernel.org/r/20221024062012.1520887-1-naoya.horiguchi@linux.dev
Link: https://lkml.kernel.org/r/20221024062012.1520887-2-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reported-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-08 17:37:21 -08:00
Peter Xu
b12fdbf15f Revert "mm/uffd: fix warning without PTE_MARKER_UFFD_WP compiled in" 
With " mm/uffd: Fix vma check on userfault for wp" to fix the
registration, we'll be safe to remove the macro hacks now.

Link: https://lkml.kernel.org/r/20221024193336.1233616-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-08 17:37:21 -08:00
Peter Xu
4781593d5d mm/hugetlb: unify clearing of RestoreReserve for private pages 
A trivial cleanup to move clearing of RestoreReserve into adding anon rmap
of private hugetlb mappings.  It matches with the shared mappings where we
only clear the bit when adding into page cache, rather than spreading it
around the code paths.

Link: https://lkml.kernel.org/r/20221020193832.776173-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-08 17:37:19 -08:00
Mike Kravetz
57a196a584 hugetlb: simplify hugetlb handling in follow_page_mask 
During discussions of this series [1], it was suggested that hugetlb
handling code in follow_page_mask could be simplified.  At the beginning
of follow_page_mask, there currently is a call to follow_huge_addr which
'may' handle hugetlb pages.  ia64 is the only architecture which provides
a follow_huge_addr routine that does not return error.  Instead, at each
level of the page table a check is made for a hugetlb entry.  If a hugetlb
entry is found, a call to a routine associated with that entry is made.

Currently, there are two checks for hugetlb entries at each page table
level.  The first check is of the form:

        if (p?d_huge())
                page = follow_huge_p?d();

the second check is of the form:

        if (is_hugepd())
                page = follow_huge_pd().

We can replace these checks, as well as the special handling routines such
as follow_huge_p?d() and follow_huge_pd() with a single routine to handle
hugetlb vmas.

A new routine hugetlb_follow_page_mask is called for hugetlb vmas at the
beginning of follow_page_mask.  hugetlb_follow_page_mask will use the
existing routine huge_pte_offset to walk page tables looking for hugetlb
entries.  huge_pte_offset can be overwritten by architectures, and already
handles special cases such as hugepd entries.

[1] https://lore.kernel.org/linux-mm/cover.1661240170.git.baolin.wang@linux.alibaba.com/

[mike.kravetz@oracle.com: remove vma (pmd sharing) per Peter]
  Link: https://lkml.kernel.org/r/20221028181108.119432-1-mike.kravetz@oracle.com
[mike.kravetz@oracle.com: remove left over hugetlb_vma_unlock_read()]
  Link: https://lkml.kernel.org/r/20221030225825.40872-1-mike.kravetz@oracle.com
Link: https://lkml.kernel.org/r/20220919021348.22151-1-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-08 17:37:10 -08:00
James Houghton
8625147caf hugetlbfs: don't delete error page from pagecache 
This change is very similar to the change that was made for shmem [1], and
it solves the same problem but for HugeTLBFS instead.

Currently, when poison is found in a HugeTLB page, the page is removed
from the page cache.  That means that attempting to map or read that
hugepage in the future will result in a new hugepage being allocated
instead of notifying the user that the page was poisoned.  As [1] states,
this is effectively memory corruption.

The fix is to leave the page in the page cache.  If the user attempts to
use a poisoned HugeTLB page with a syscall, the syscall will fail with
EIO, the same error code that shmem uses.  For attempts to map the page,
the thread will get a BUS_MCEERR_AR SIGBUS.

[1]: commit a760542666 ("mm: shmem: don't truncate page if memory failure happens")

Link: https://lkml.kernel.org/r/20221018200125.848471-1-jthoughton@google.com
Signed-off-by: James Houghton <jthoughton@google.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Tested-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: James Houghton <jthoughton@google.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-11-08 15:57:22 -08:00
Mike Kravetz
612b8a3170 hugetlb: fix memory leak associated with vma_lock structure 
The hugetlb vma_lock structure hangs off the vm_private_data pointer of
sharable hugetlb vmas.  The structure is vma specific and can not be
shared between vmas.  At fork and various other times, vmas are duplicated
via vm_area_dup().  When this happens, the pointer in the newly created
vma must be cleared and the structure reallocated.  Two hugetlb specific
routines deal with this hugetlb_dup_vma_private and hugetlb_vm_op_open. 
Both routines are called for newly created vmas.  hugetlb_dup_vma_private
would always clear the pointer and hugetlb_vm_op_open would allocate the
new vms_lock structure.  This did not work in the case of this calling
sequence pointed out in [1].

  move_vma
    copy_vma
      new_vma = vm_area_dup(vma);
      new_vma->vm_ops->open(new_vma); --> new_vma has its own vma lock.
    is_vm_hugetlb_page(vma)
      clear_vma_resv_huge_pages
        hugetlb_dup_vma_private --> vma->vm_private_data is set to NULL

When clearing hugetlb_dup_vma_private we actually leak the associated
vma_lock structure.

The vma_lock structure contains a pointer to the associated vma.  This
information can be used in hugetlb_dup_vma_private and hugetlb_vm_op_open
to ensure we only clear the vm_private_data of newly created (copied)
vmas.  In such cases, the vma->vma_lock->vma field will not point to the
vma.

Update hugetlb_dup_vma_private and hugetlb_vm_op_open to not clear
vm_private_data if vma->vma_lock->vma == vma.  Also, log a warning if
hugetlb_vm_op_open ever encounters the case where vma_lock has already
been correctly allocated for the vma.

[1] https://lore.kernel.org/linux-mm/5154292a-4c55-28cd-0935-82441e512fc3@huawei.com/

Link: https://lkml.kernel.org/r/20221019201957.34607-1-mike.kravetz@oracle.com
Fixes: 131a79b474 ("hugetlb: fix vma lock handling during split vma and range unmapping")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: James Houghton <jthoughton@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Prakash Sangappa <prakash.sangappa@oracle.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-10-20 21:27:23 -07:00
Rik van Riel
12df140f0b mm,hugetlb: take hugetlb_lock before decrementing h->resv_huge_pages 
The h->*_huge_pages counters are protected by the hugetlb_lock, but
alloc_huge_page has a corner case where it can decrement the counter
outside of the lock.

This could lead to a corrupted value of h->resv_huge_pages, which we have
observed on our systems.

Take the hugetlb_lock before decrementing h->resv_huge_pages to avoid a
potential race.

Link: https://lkml.kernel.org/r/20221017202505.0e6a4fcd@imladris.surriel.com
Fixes: a88c769548 ("mm: hugetlb: fix hugepage memory leak caused by wrong reserve count")
Signed-off-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Glen McCready <gkmccready@meta.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-10-20 21:27:23 -07:00
Linus Torvalds
5e714bf171 - Alistair Popple has a series which addresses a race which causes page 
refcounting errors in ZONE_DEVICE pages.
 
 - Peter Xu fixes some userfaultfd test harness instability.
 
 - Various other patches in MM, mainly fixes.
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Merge tag 'mm-stable-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull more MM updates from Andrew Morton:

 - fix a race which causes page refcounting errors in ZONE_DEVICE pages
   (Alistair Popple)

 - fix userfaultfd test harness instability (Peter Xu)

 - various other patches in MM, mainly fixes

* tag 'mm-stable-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (29 commits)
  highmem: fix kmap_to_page() for kmap_local_page() addresses
  mm/page_alloc: fix incorrect PGFREE and PGALLOC for high-order page
  mm/selftest: uffd: explain the write missing fault check
  mm/hugetlb: use hugetlb_pte_stable in migration race check
  mm/hugetlb: fix race condition of uffd missing/minor handling
  zram: always expose rw_page
  LoongArch: update local TLB if PTE entry exists
  mm: use update_mmu_tlb() on the second thread
  kasan: fix array-bounds warnings in tests
  hmm-tests: add test for migrate_device_range()
  nouveau/dmem: evict device private memory during release
  nouveau/dmem: refactor nouveau_dmem_fault_copy_one()
  mm/migrate_device.c: add migrate_device_range()
  mm/migrate_device.c: refactor migrate_vma and migrate_deivce_coherent_page()
  mm/memremap.c: take a pgmap reference on page allocation
  mm: free device private pages have zero refcount
  mm/memory.c: fix race when faulting a device private page
  mm/damon: use damon_sz_region() in appropriate place
  mm/damon: move sz_damon_region to damon_sz_region
  lib/test_meminit: add checks for the allocation functions
  ...
 2022-10-14 12:28:43 -07:00
Peter Xu
f9bf6c03ec mm/hugetlb: use hugetlb_pte_stable in migration race check 
After hugetlb_pte_stable() introduced, we can also rewrite the migration
race condition against page allocation to use the new helper too.

Link: https://lkml.kernel.org/r/20221004193400.110155-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-10-12 18:51:50 -07:00
Peter Xu
2ea7ff1e39 mm/hugetlb: fix race condition of uffd missing/minor handling 
Patch series "mm/hugetlb: Fix selftest failures with write check", v3.

Currently akpm mm-unstable fails with uffd hugetlb private mapping test
randomly on a write check.

The initial bisection of that points to the recent pmd unshare series, but
it turns out there's no direction relationship with the series but only
some timing change caused the race to start trigger.

The race should be fixed in patch 1.  Patch 2 is a trivial cleanup on the
similar race with hugetlb migrations, patch 3 comment on the write check
so when anyone read it again it'll be clear why it's there.


This patch (of 3):

After the recent rework patchset of hugetlb locking on pmd sharing,
kselftest for userfaultfd sometimes fails on hugetlb private tests with
unexpected write fault checks.

It turns out there's nothing wrong within the locking series regarding
this matter, but it could have changed the timing of threads so it can
trigger an old bug.

The real bug is when we call hugetlb_no_page() we're not with the pgtable
lock.  It means we're reading the pte values lockless.  It's perfectly
fine in most cases because before we do normal page allocations we'll take
the lock and check pte_same() again.  However before that, there are
actually two paths on userfaultfd missing/minor handling that may directly
move on with the fault process without checking the pte values.

It means for these two paths we may be generating an uffd message based on
an unstable pte, while an unstable pte can legally be anything as long as
the modifier holds the pgtable lock.

One example, which is also what happened in the failing kselftest and
caused the test failure, is that for private mappings wr-protection
changes can happen on one page.  While hugetlb_change_protection()
generally requires pte being cleared before being changed, then there can
be a race condition like:

        thread 1                              thread 2
        --------                              --------

      UFFDIO_WRITEPROTECT                     hugetlb_fault
        hugetlb_change_protection
          pgtable_lock()
          huge_ptep_modify_prot_start
                                              pte==NULL
                                              hugetlb_no_page
                                                generate uffd missing event
                                                even if page existed!!
          huge_ptep_modify_prot_commit
          pgtable_unlock()

Fix this by rechecking the pte after pgtable lock for both userfaultfd
missing & minor fault paths.

This bug should have been around starting from uffd hugetlb introduced, so
attaching a Fixes to the commit.  Also attach another Fixes to the minor
support commit for easier tracking.

Note that userfaultfd is actually fine with false positives (e.g.  caused
by pte changed), but not wrong logical events (e.g.  caused by reading a
pte during changing).  The latter can confuse the userspace, so the
strictness is very much preferred.  E.g., MISSING event should never
happen on the page after UFFDIO_COPY has correctly installed the page and
returned.

Link: https://lkml.kernel.org/r/20221004193400.110155-1-peterx@redhat.com
Link: https://lkml.kernel.org/r/20221004193400.110155-2-peterx@redhat.com
Fixes: 1a1aad8a9b ("userfaultfd: hugetlbfs: add userfaultfd hugetlb hook")
Fixes: 7677f7fd8b ("userfaultfd: add minor fault registration mode")
Signed-off-by: Peter Xu <peterx@redhat.com>
Co-developed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-10-12 18:51:50 -07:00
Peter Xu
515778e2d7 mm/uffd: fix warning without PTE_MARKER_UFFD_WP compiled in 
When PTE_MARKER_UFFD_WP not configured, it's still possible to reach pte
marker code and trigger an warning. Add a few CONFIG_PTE_MARKER_UFFD_WP
ifdefs to make sure the code won't be reached when not compiled in.

Link: https://lkml.kernel.org/r/YzeR+R6b4bwBlBHh@x1n
Fixes: b1f9e87686 ("mm/uffd: enable write protection for shmem & hugetlbfs")
Signed-off-by: Peter Xu <peterx@redhat.com>
Reported-by: <syzbot+2b9b4f0895be09a6dec3@syzkaller.appspotmail.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Edward Liaw <edliaw@google.com>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-10-12 15:56:46 -07:00
Andrew Morton
acfac37851 mm/hugetlb.c: make __hugetlb_vma_unlock_write_put() static 
Reported-by: kernel test robot <lkp@intel.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-10-12 15:56:45 -07:00
Linus Torvalds
1440f57602 Five hotfixes - three for nilfs2, two for MM. For are cc:stable, one is 
not.
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Merge tag 'mm-hotfixes-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc hotfixes from Andrew Morton:
 "Five hotfixes - three for nilfs2, two for MM. For are cc:stable, one
  is not"

* tag 'mm-hotfixes-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  nilfs2: fix leak of nilfs_root in case of writer thread creation failure
  nilfs2: fix NULL pointer dereference at nilfs_bmap_lookup_at_level()
  nilfs2: fix use-after-free bug of struct nilfs_root
  mm/damon/core: initialize damon_target->list in damon_new_target()
  mm/hugetlb: fix races when looking up a CONT-PTE/PMD size hugetlb page
 2022-10-12 11:16:58 -07:00
Baolin Wang
fac35ba763 mm/hugetlb: fix races when looking up a CONT-PTE/PMD size hugetlb page 
On some architectures (like ARM64), it can support CONT-PTE/PMD size
hugetlb, which means it can support not only PMD/PUD size hugetlb (2M and
1G), but also CONT-PTE/PMD size(64K and 32M) if a 4K page size specified.

So when looking up a CONT-PTE size hugetlb page by follow_page(), it will
use pte_offset_map_lock() to get the pte entry lock for the CONT-PTE size
hugetlb in follow_page_pte().  However this pte entry lock is incorrect
for the CONT-PTE size hugetlb, since we should use huge_pte_lock() to get
the correct lock, which is mm->page_table_lock.

That means the pte entry of the CONT-PTE size hugetlb under current pte
lock is unstable in follow_page_pte(), we can continue to migrate or
poison the pte entry of the CONT-PTE size hugetlb, which can cause some
potential race issues, even though they are under the 'pte lock'.

For example, suppose thread A is trying to look up a CONT-PTE size hugetlb
page by move_pages() syscall under the lock, however antoher thread B can
migrate the CONT-PTE hugetlb page at the same time, which will cause
thread A to get an incorrect page, if thread A also wants to do page
migration, then data inconsistency error occurs.

Moreover we have the same issue for CONT-PMD size hugetlb in
follow_huge_pmd().

To fix above issues, rename the follow_huge_pmd() as follow_huge_pmd_pte()
to handle PMD and PTE level size hugetlb, which uses huge_pte_lock() to
get the correct pte entry lock to make the pte entry stable.

Mike said:

Support for CONT_PMD/_PTE was added with bb9dd3df8e ("arm64: hugetlb:
refactor find_num_contig()").  Patch series "Support for contiguous pte
hugepages", v4.  However, I do not believe these code paths were
executed until migration support was added with 5480280d3f ("arm64/mm:
enable HugeTLB migration for contiguous bit HugeTLB pages") I would go
with 5480280d3f for the Fixes: targe.

Link: https://lkml.kernel.org/r/635f43bdd85ac2615a58405da82b4d33c6e5eb05.1662017562.git.baolin.wang@linux.alibaba.com
Fixes: 5480280d3f ("arm64/mm: enable HugeTLB migration for contiguous bit HugeTLB pages")
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Suggested-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-10-11 19:05:44 -07:00
Mike Kravetz
bbff39cc6c hugetlb: allocate vma lock for all sharable vmas 
The hugetlb vma lock was originally designed to synchronize pmd sharing. 
As such, it was only necessary to allocate the lock for vmas that were
capable of pmd sharing.  Later in the development cycle, it was discovered
that it could also be used to simplify fault/truncation races as described
in [1].  However, a subsequent change to allocate the lock for all vmas
that use the page cache was never made.  A fault/truncation race could
leave pages in a file past i_size until the file is removed.

Remove the previous restriction and allocate lock for all VM_MAYSHARE
vmas.  Warn in the unlikely event of allocation failure.

[1] https://lore.kernel.org/lkml/Yxiv0SkMkZ0JWGGp@monkey/#t

Link: https://lkml.kernel.org/r/20221005011707.514612-4-mike.kravetz@oracle.com
Fixes: "hugetlb: clean up code checking for fault/truncation races"
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: James Houghton <jthoughton@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Prakash Sangappa <prakash.sangappa@oracle.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-10-07 14:28:40 -07:00
Mike Kravetz
ecfbd73387 hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer 
hugetlb file truncation/hole punch code may need to back out and take
locks in order in the routine hugetlb_unmap_file_folio().  This code could
race with vma freeing as pointed out in [1] and result in accessing a
stale vma pointer.  To address this, take the vma_lock when clearing the
vma_lock->vma pointer.

[1] https://lore.kernel.org/linux-mm/01f10195-7088-4462-6def-909549c75ef4@huawei.com/

[mike.kravetz@oracle.com: address build issues]
  Link: https://lkml.kernel.org/r/Yz5L1uxQYR1VqFtJ@monkey
Link: https://lkml.kernel.org/r/20221005011707.514612-3-mike.kravetz@oracle.com
Fixes: "hugetlb: use new vma_lock for pmd sharing synchronization"
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: James Houghton <jthoughton@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Prakash Sangappa <prakash.sangappa@oracle.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-10-07 14:28:40 -07:00
Mike Kravetz
131a79b474 hugetlb: fix vma lock handling during split vma and range unmapping 
Patch series "hugetlb: fixes for new vma lock series".

In review of the series "hugetlb: Use new vma lock for huge pmd sharing
synchronization", Miaohe Lin pointed out two key issues:

1) There is a race in the routine hugetlb_unmap_file_folio when locks
   are dropped and reacquired in the correct order [1].

2) With the switch to using vma lock for fault/truncate synchronization,
   we need to make sure lock exists for all VM_MAYSHARE vmas, not just
   vmas capable of pmd sharing.

These two issues are addressed here.  In addition, having a vma lock
present in all VM_MAYSHARE vmas, uncovered some issues around vma
splitting.  Those are also addressed.

[1] https://lore.kernel.org/linux-mm/01f10195-7088-4462-6def-909549c75ef4@huawei.com/


This patch (of 3):

The hugetlb vma lock hangs off the vm_private_data field and is specific
to the vma.  When vm_area_dup() is called as part of vma splitting, the
vma lock pointer is copied to the new vma.  This will result in issues
such as double freeing of the structure.  Update the hugetlb open vm_ops
to allocate a new vma lock for the new vma.

The routine __unmap_hugepage_range_final unconditionally unset VM_MAYSHARE
to prevent subsequent pmd sharing.  hugetlb_vma_lock_free attempted to
anticipate this by checking both VM_MAYSHARE and VM_SHARED.  However, if
only VM_MAYSHARE was set we would miss the free.  With the introduction of
the vma lock, a vma can not participate in pmd sharing if vm_private_data
is NULL.  Instead of clearing VM_MAYSHARE in __unmap_hugepage_range_final,
free the vma lock to prevent sharing.  Also, update the sharing code to
make sure vma lock is indeed a condition for pmd sharing. 
hugetlb_vma_lock_free can then key off VM_MAYSHARE and not miss any vmas.

Link: https://lkml.kernel.org/r/20221005011707.514612-1-mike.kravetz@oracle.com
Link: https://lkml.kernel.org/r/20221005011707.514612-2-mike.kravetz@oracle.com
Fixes: "hugetlb: add vma based lock for pmd sharing"
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: James Houghton <jthoughton@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Prakash Sangappa <prakash.sangappa@oracle.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-10-07 14:28:40 -07:00
Xin Hao
8346d69d8b mm/hugetlb: add available_huge_pages() func 
In hugetlb.c there are several places which compare the values of
'h->free_huge_pages' and 'h->resv_huge_pages', it looks a bit messy, so
add a new available_huge_pages() function to do these.

Link: https://lkml.kernel.org/r/20220922021929.98961-1-xhao@linux.alibaba.com
Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2022-10-03 14:03:35 -07:00