History log of /openbmc/linux/mm/gup.c (Results 201 – 225 of 1609)
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# a63f7778 08-Jul-2022 Dmitry Torokhov <dmitry.torokhov@gmail.com>

Merge tag 'v5.19-rc5' into next

Merge with mainline to bring up the latest definition from MFD subsystem
needed for Mediatek keypad driver.


# dd84cfff 04-Jul-2022 Takashi Iwai <tiwai@suse.de>

Merge tag 'asoc-fix-v5.19-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v5.19

A collection of fixes for v5.19, quite large but nothing major -

Merge tag 'asoc-fix-v5.19-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v5.19

A collection of fixes for v5.19, quite large but nothing major - a good
chunk of it is more stuff that was identified by mixer-test regarding
event generation.

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# 7ce82f4c 30-May-2022 Miaohe Lin <linmiaohe@huawei.com>

mm/migration: return errno when isolate_huge_page failed

We might fail to isolate huge page due to e.g. the page is under
migration which cleared HPageMigratable. We should return errno in this
ca

mm/migration: return errno when isolate_huge_page failed

We might fail to isolate huge page due to e.g. the page is under
migration which cleared HPageMigratable. We should return errno in this
case rather than always return 1 which could confuse the user, i.e. the
caller might think all of the memory is migrated while the hugetlb page is
left behind. We make the prototype of isolate_huge_page consistent with
isolate_lru_page as suggested by Huang Ying and rename isolate_huge_page
to isolate_hugetlb as suggested by Muchun to improve the readability.

Link: https://lkml.kernel.org/r/20220530113016.16663-4-linmiaohe@huawei.com
Fixes: e8db67eb0ded ("mm: migrate: move_pages() supports thp migration")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Suggested-by: Huang Ying <ying.huang@intel.com>
Reported-by: kernel test robot <lkp@intel.com> (build error)
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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# 2b1333b8 20-Jun-2022 Thomas Zimmermann <tzimmermann@suse.de>

Merge drm/drm-next into drm-misc-next

Backmerging to get new regmap APIs of v5.19-rc1.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>


# d9272525 30-May-2022 Peter Xu <peterx@redhat.com>

mm: avoid unnecessary page fault retires on shared memory types

I observed that for each of the shared file-backed page faults, we're very
likely to retry one more time for the 1st write fault upon

mm: avoid unnecessary page fault retires on shared memory types

I observed that for each of the shared file-backed page faults, we're very
likely to retry one more time for the 1st write fault upon no page. It's
because we'll need to release the mmap lock for dirty rate limit purpose
with balance_dirty_pages_ratelimited() (in fault_dirty_shared_page()).

Then after that throttling we return VM_FAULT_RETRY.

We did that probably because VM_FAULT_RETRY is the only way we can return
to the fault handler at that time telling it we've released the mmap lock.

However that's not ideal because it's very likely the fault does not need
to be retried at all since the pgtable was well installed before the
throttling, so the next continuous fault (including taking mmap read lock,
walk the pgtable, etc.) could be in most cases unnecessary.

It's not only slowing down page faults for shared file-backed, but also add
more mmap lock contention which is in most cases not needed at all.

To observe this, one could try to write to some shmem page and look at
"pgfault" value in /proc/vmstat, then we should expect 2 counts for each
shmem write simply because we retried, and vm event "pgfault" will capture
that.

To make it more efficient, add a new VM_FAULT_COMPLETED return code just to
show that we've completed the whole fault and released the lock. It's also
a hint that we should very possibly not need another fault immediately on
this page because we've just completed it.

This patch provides a ~12% perf boost on my aarch64 test VM with a simple
program sequentially dirtying 400MB shmem file being mmap()ed and these are
the time it needs:

Before: 650.980 ms (+-1.94%)
After: 569.396 ms (+-1.38%)

I believe it could help more than that.

We need some special care on GUP and the s390 pgfault handler (for gmap
code before returning from pgfault), the rest changes in the page fault
handlers should be relatively straightforward.

Another thing to mention is that mm_account_fault() does take this new
fault as a generic fault to be accounted, unlike VM_FAULT_RETRY.

I explicitly didn't touch hmm_vma_fault() and break_ksm() because they do
not handle VM_FAULT_RETRY even with existing code, so I'm literally keeping
them as-is.

Link: https://lkml.kernel.org/r/20220530183450.42886-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vineet Gupta <vgupta@kernel.org>
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [arm part]
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Stafford Horne <shorne@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Richard Weinberger <richard@nod.at>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Will Deacon <will@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Chris Zankel <chris@zankel.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Rich Felker <dalias@libc.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Helge Deller <deller@gmx.de>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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# f777316e 15-Jun-2022 Takashi Iwai <tiwai@suse.de>

Merge branch 'topic/ctl-enhancements' into for-next

Pull ALSA control enhancement patches.
One is the faster lookup of control elements, and another is to
introduce the input data validation.

Signe

Merge branch 'topic/ctl-enhancements' into for-next

Pull ALSA control enhancement patches.
One is the faster lookup of control elements, and another is to
introduce the input data validation.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

show more ...


# 66da6500 09-Jun-2022 Paolo Bonzini <pbonzini@redhat.com>

Merge tag 'kvm-riscv-fixes-5.19-1' of https://github.com/kvm-riscv/linux into HEAD

KVM/riscv fixes for 5.19, take #1

- Typo fix in arch/riscv/kvm/vmid.c

- Remove broken reference pattern from MAIN

Merge tag 'kvm-riscv-fixes-5.19-1' of https://github.com/kvm-riscv/linux into HEAD

KVM/riscv fixes for 5.19, take #1

- Typo fix in arch/riscv/kvm/vmid.c

- Remove broken reference pattern from MAINTAINERS entry

show more ...


# 6e2b347d 08-Jun-2022 Maxime Ripard <maxime@cerno.tech>

Merge v5.19-rc1 into drm-misc-fixes

Let's kick-off the start of the 5.19 fix cycle

Signed-off-by: Maxime Ripard <maxime@cerno.tech>


# 073350da 07-Jun-2022 Mark Brown <broonie@kernel.org>

Merge tag 'v5.19-rc1' into asoc-5.19

Linux 5.19-rc1


# 03ab8e62 31-May-2022 Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

Merge tag 'v5.18'

Linux 5.18


# 690e1790 27-May-2022 Dmitry Torokhov <dmitry.torokhov@gmail.com>

Merge tag 'v5.18' into next

Sync up with mainline to get updates to OMAP4 keypad driver and other
upstream goodies.


# 98931dd9 26-May-2022 Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:
"Almost all of MM here. A few things are still getting finished off,

Merge tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:
"Almost all of MM here. A few things are still getting finished off,
reviewed, etc.

- Yang Shi has improved the behaviour of khugepaged collapsing of
readonly file-backed transparent hugepages.

- Johannes Weiner has arranged for zswap memory use to be tracked and
managed on a per-cgroup basis.

- Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for
runtime enablement of the recent huge page vmemmap optimization
feature.

- Baolin Wang contributes a series to fix some issues around hugetlb
pagetable invalidation.

- Zhenwei Pi has fixed some interactions between hwpoisoned pages and
virtualization.

- Tong Tiangen has enabled the use of the presently x86-only
page_table_check debugging feature on arm64 and riscv.

- David Vernet has done some fixup work on the memcg selftests.

- Peter Xu has taught userfaultfd to handle write protection faults
against shmem- and hugetlbfs-backed files.

- More DAMON development from SeongJae Park - adding online tuning of
the feature and support for monitoring of fixed virtual address
ranges. Also easier discovery of which monitoring operations are
available.

- Nadav Amit has done some optimization of TLB flushing during
mprotect().

- Neil Brown continues to labor away at improving our swap-over-NFS
support.

- David Hildenbrand has some fixes to anon page COWing versus
get_user_pages().

- Peng Liu fixed some errors in the core hugetlb code.

- Joao Martins has reduced the amount of memory consumed by
device-dax's compound devmaps.

- Some cleanups of the arch-specific pagemap code from Anshuman
Khandual.

- Muchun Song has found and fixed some errors in the TLB flushing of
transparent hugepages.

- Roman Gushchin has done more work on the memcg selftests.

... and, of course, many smaller fixes and cleanups. Notably, the
customary million cleanup serieses from Miaohe Lin"

* tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (381 commits)
mm: kfence: use PAGE_ALIGNED helper
selftests: vm: add the "settings" file with timeout variable
selftests: vm: add "test_hmm.sh" to TEST_FILES
selftests: vm: check numa_available() before operating "merge_across_nodes" in ksm_tests
selftests: vm: add migration to the .gitignore
selftests/vm/pkeys: fix typo in comment
ksm: fix typo in comment
selftests: vm: add process_mrelease tests
Revert "mm/vmscan: never demote for memcg reclaim"
mm/kfence: print disabling or re-enabling message
include/trace/events/percpu.h: cleanup for "percpu: improve percpu_alloc_percpu event trace"
include/trace/events/mmflags.h: cleanup for "tracing: incorrect gfp_t conversion"
mm: fix a potential infinite loop in start_isolate_page_range()
MAINTAINERS: add Muchun as co-maintainer for HugeTLB
zram: fix Kconfig dependency warning
mm/shmem: fix shmem folio swapoff hang
cgroup: fix an error handling path in alloc_pagecache_max_30M()
mm: damon: use HPAGE_PMD_SIZE
tracing: incorrect isolate_mote_t cast in mm_vmscan_lru_isolate
nodemask.h: fix compilation error with GCC12
...

show more ...


# 143a6252 23-May-2022 Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:

- Initial support for the ARMv9 Scalable Matrix Extension (SME).

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:

- Initial support for the ARMv9 Scalable Matrix Extension (SME).

SME takes the approach used for vectors in SVE and extends this to
provide architectural support for matrix operations. No KVM support
yet, SME is disabled in guests.

- Support for crashkernel reservations above ZONE_DMA via the
'crashkernel=X,high' command line option.

- btrfs search_ioctl() fix for live-lock with sub-page faults.

- arm64 perf updates: support for the Hisilicon "CPA" PMU for
monitoring coherent I/O traffic, support for Arm's CMN-650 and
CMN-700 interconnect PMUs, minor driver fixes, kerneldoc cleanup.

- Kselftest updates for SME, BTI, MTE.

- Automatic generation of the system register macros from a 'sysreg'
file describing the register bitfields.

- Update the type of the function argument holding the ESR_ELx register
value to unsigned long to match the architecture register size
(originally 32-bit but extended since ARMv8.0).

- stacktrace cleanups.

- ftrace cleanups.

- Miscellaneous updates, most notably: arm64-specific huge_ptep_get(),
avoid executable mappings in kexec/hibernate code, drop TLB flushing
from get_clear_flush() (and rename it to get_clear_contig()),
ARCH_NR_GPIO bumped to 2048 for ARCH_APPLE.

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (145 commits)
arm64/sysreg: Generate definitions for FAR_ELx
arm64/sysreg: Generate definitions for DACR32_EL2
arm64/sysreg: Generate definitions for CSSELR_EL1
arm64/sysreg: Generate definitions for CPACR_ELx
arm64/sysreg: Generate definitions for CONTEXTIDR_ELx
arm64/sysreg: Generate definitions for CLIDR_EL1
arm64/sve: Move sve_free() into SVE code section
arm64: Kconfig.platforms: Add comments
arm64: Kconfig: Fix indentation and add comments
arm64: mm: avoid writable executable mappings in kexec/hibernate code
arm64: lds: move special code sections out of kernel exec segment
arm64/hugetlb: Implement arm64 specific huge_ptep_get()
arm64/hugetlb: Use ptep_get() to get the pte value of a huge page
arm64: kdump: Do not allocate crash low memory if not needed
arm64/sve: Generate ZCR definitions
arm64/sme: Generate defintions for SVCR
arm64/sme: Generate SMPRI_EL1 definitions
arm64/sme: Automatically generate SMPRIMAP_EL2 definitions
arm64/sme: Automatically generate SMIDR_EL1 defines
arm64/sme: Automatically generate defines for SMCR
...

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# 201729d5 20-May-2022 Catalin Marinas <catalin.marinas@arm.com>

Merge branches 'for-next/sme', 'for-next/stacktrace', 'for-next/fault-in-subpage', 'for-next/misc', 'for-next/ftrace' and 'for-next/crashkernel', remote-tracking branch 'arm64/for-next/perf' into for

Merge branches 'for-next/sme', 'for-next/stacktrace', 'for-next/fault-in-subpage', 'for-next/misc', 'for-next/ftrace' and 'for-next/crashkernel', remote-tracking branch 'arm64/for-next/perf' into for-next/core

* arm64/for-next/perf:
perf/arm-cmn: Decode CAL devices properly in debugfs
perf/arm-cmn: Fix filter_sel lookup
perf/marvell_cn10k: Fix tad_pmu_event_init() to check pmu type first
drivers/perf: hisi: Add Support for CPA PMU
drivers/perf: hisi: Associate PMUs in SICL with CPUs online
drivers/perf: arm_spe: Expose saturating counter to 16-bit
perf/arm-cmn: Add CMN-700 support
perf/arm-cmn: Refactor occupancy filter selector
perf/arm-cmn: Add CMN-650 support
dt-bindings: perf: arm-cmn: Add CMN-650 and CMN-700
perf: check return value of armpmu_request_irq()
perf: RISC-V: Remove non-kernel-doc ** comments

* for-next/sme: (30 commits)
: Scalable Matrix Extensions support.
arm64/sve: Move sve_free() into SVE code section
arm64/sve: Make kernel FPU protection RT friendly
arm64/sve: Delay freeing memory in fpsimd_flush_thread()
arm64/sme: More sensibly define the size for the ZA register set
arm64/sme: Fix NULL check after kzalloc
arm64/sme: Add ID_AA64SMFR0_EL1 to __read_sysreg_by_encoding()
arm64/sme: Provide Kconfig for SME
KVM: arm64: Handle SME host state when running guests
KVM: arm64: Trap SME usage in guest
KVM: arm64: Hide SME system registers from guests
arm64/sme: Save and restore streaming mode over EFI runtime calls
arm64/sme: Disable streaming mode and ZA when flushing CPU state
arm64/sme: Add ptrace support for ZA
arm64/sme: Implement ptrace support for streaming mode SVE registers
arm64/sme: Implement ZA signal handling
arm64/sme: Implement streaming SVE signal handling
arm64/sme: Disable ZA and streaming mode when handling signals
arm64/sme: Implement traps and syscall handling for SME
arm64/sme: Implement ZA context switching
arm64/sme: Implement streaming SVE context switching
...

* for-next/stacktrace:
: Stacktrace cleanups.
arm64: stacktrace: align with common naming
arm64: stacktrace: rename stackframe to unwind_state
arm64: stacktrace: rename unwinder functions
arm64: stacktrace: make struct stackframe private to stacktrace.c
arm64: stacktrace: delete PCS comment
arm64: stacktrace: remove NULL task check from unwind_frame()

* for-next/fault-in-subpage:
: btrfs search_ioctl() live-lock fix using fault_in_subpage_writeable().
btrfs: Avoid live-lock in search_ioctl() on hardware with sub-page faults
arm64: Add support for user sub-page fault probing
mm: Add fault_in_subpage_writeable() to probe at sub-page granularity

* for-next/misc:
: Miscellaneous patches.
arm64: Kconfig.platforms: Add comments
arm64: Kconfig: Fix indentation and add comments
arm64: mm: avoid writable executable mappings in kexec/hibernate code
arm64: lds: move special code sections out of kernel exec segment
arm64/hugetlb: Implement arm64 specific huge_ptep_get()
arm64/hugetlb: Use ptep_get() to get the pte value of a huge page
arm64: mm: Make arch_faults_on_old_pte() check for migratability
arm64: mte: Clean up user tag accessors
arm64/hugetlb: Drop TLB flush from get_clear_flush()
arm64: Declare non global symbols as static
arm64: mm: Cleanup useless parameters in zone_sizes_init()
arm64: fix types in copy_highpage()
arm64: Set ARCH_NR_GPIO to 2048 for ARCH_APPLE
arm64: cputype: Avoid overflow using MIDR_IMPLEMENTOR_MASK
arm64: document the boot requirements for MTE
arm64/mm: Compute PTRS_PER_[PMD|PUD] independently of PTRS_PER_PTE

* for-next/ftrace:
: ftrace cleanups.
arm64/ftrace: Make function graph use ftrace directly
ftrace: cleanup ftrace_graph_caller enable and disable

* for-next/crashkernel:
: Support for crashkernel reservations above ZONE_DMA.
arm64: kdump: Do not allocate crash low memory if not needed
docs: kdump: Update the crashkernel description for arm64
of: Support more than one crash kernel regions for kexec -s
of: fdt: Add memory for devices by DT property "linux,usable-memory-range"
arm64: kdump: Reimplement crashkernel=X
arm64: Use insert_resource() to simplify code
kdump: return -ENOENT if required cmdline option does not exist

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# 0768c8de 09-May-2022 Yury Norov <yury.norov@gmail.com>

mm/gup: fix comments to pin_user_pages_*()

pin_user_pages API forces FOLL_PIN in gup_flags, which means that the API
requires struct page **pages to be provided (not NULL). However, the
comment to

mm/gup: fix comments to pin_user_pages_*()

pin_user_pages API forces FOLL_PIN in gup_flags, which means that the API
requires struct page **pages to be provided (not NULL). However, the
comment to pin_user_pages() clearly allows for passing in a NULL @pages
argument.

Remove the incorrect comments, and add WARN_ON_ONCE(!pages) calls to
enforce the API.

It has been independently spotted by Minchan Kim and confirmed with
John Hubbard:

https://lore.kernel.org/all/YgWA0ghrrzHONehH@google.com/

Link: https://lkml.kernel.org/r/20220422015839.1274328-1-yury.norov@gmail.com
Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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# b6a2619c 09-May-2022 David Hildenbrand <david@redhat.com>

mm/gup: sanity-check with CONFIG_DEBUG_VM that anonymous pages are exclusive when (un)pinning

Let's verify when (un)pinning anonymous pages that we always deal with
exclusive anonymous pages, which

mm/gup: sanity-check with CONFIG_DEBUG_VM that anonymous pages are exclusive when (un)pinning

Let's verify when (un)pinning anonymous pages that we always deal with
exclusive anonymous pages, which guarantees that we'll have a reliable
PIN, meaning that we cannot end up with the GUP pin being inconsistent
with he pages mapped into the page tables due to a COW triggered by a
write fault.

When pinning pages, after conditionally triggering GUP unsharing of
possibly shared anonymous pages, we should always only see exclusive
anonymous pages. Note that anonymous pages that are mapped writable must
be marked exclusive, otherwise we'd have a BUG.

When pinning during ordinary GUP, simply add a check after our conditional
GUP-triggered unsharing checks. As we know exactly how the page is
mapped, we know exactly in which page we have to check for
PageAnonExclusive().

When pinning via GUP-fast we have to be careful, because we can race with
fork(): verify only after we made sure via the seqcount that we didn't
race with concurrent fork() that we didn't end up pinning a possibly
shared anonymous page.

Similarly, when unpinning, verify that the pages are still marked as
exclusive: otherwise something turned the pages possibly shared, which can
result in random memory corruptions, which we really want to catch.

With only the pinned pages at hand and not the actual page table entries
we have to be a bit careful: hugetlb pages are always mapped via a single
logical page table entry referencing the head page and PG_anon_exclusive
of the head page applies. Anon THP are a bit more complicated, because we
might have obtained the page reference either via a PMD or a PTE --
depending on the mapping type we either have to check PageAnonExclusive of
the head page (PMD-mapped THP) or the tail page (PTE-mapped THP) applies:
as we don't know and to make our life easier, check that either is set.

Take care to not verify in case we're unpinning during GUP-fast because we
detected concurrent fork(): we might stumble over an anonymous page that
is now shared.

Link: https://lkml.kernel.org/r/20220428083441.37290-18-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Liang Zhang <zhangliang5@huawei.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Oded Gabbay <oded.gabbay@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pedro Demarchi Gomes <pedrodemargomes@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...


# a7f22660 09-May-2022 David Hildenbrand <david@redhat.com>

mm/gup: trigger FAULT_FLAG_UNSHARE when R/O-pinning a possibly shared anonymous page

Whenever GUP currently ends up taking a R/O pin on an anonymous page that
might be shared -- mapped R/O and !Page

mm/gup: trigger FAULT_FLAG_UNSHARE when R/O-pinning a possibly shared anonymous page

Whenever GUP currently ends up taking a R/O pin on an anonymous page that
might be shared -- mapped R/O and !PageAnonExclusive() -- any write fault
on the page table entry will end up replacing the mapped anonymous page
due to COW, resulting in the GUP pin no longer being consistent with the
page actually mapped into the page table.

The possible ways to deal with this situation are:
(1) Ignore and pin -- what we do right now.
(2) Fail to pin -- which would be rather surprising to callers and
could break user space.
(3) Trigger unsharing and pin the now exclusive page -- reliable R/O
pins.

Let's implement 3) because it provides the clearest semantics and allows
for checking in unpin_user_pages() and friends for possible BUGs: when
trying to unpin a page that's no longer exclusive, clearly something went
very wrong and might result in memory corruptions that might be hard to
debug. So we better have a nice way to spot such issues.

This change implies that whenever user space *wrote* to a private mapping
(IOW, we have an anonymous page mapped), that GUP pins will always remain
consistent: reliable R/O GUP pins of anonymous pages.

As a side note, this commit fixes the COW security issue for hugetlb with
FOLL_PIN as documented in:
https://lore.kernel.org/r/3ae33b08-d9ef-f846-56fb-645e3b9b4c66@redhat.com
The vmsplice reproducer still applies, because vmsplice uses FOLL_GET
instead of FOLL_PIN.

Note that follow_huge_pmd() doesn't apply because we cannot end up in
there with FOLL_PIN.

This commit is heavily based on prototype patches by Andrea.

Link: https://lkml.kernel.org/r/20220428083441.37290-17-david@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Co-developed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Liang Zhang <zhangliang5@huawei.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Oded Gabbay <oded.gabbay@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pedro Demarchi Gomes <pedrodemargomes@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...


# 8909691b 09-May-2022 David Hildenbrand <david@redhat.com>

mm/gup: disallow follow_page(FOLL_PIN)

We want to change the way we handle R/O pins on anonymous pages that might
be shared: if we detect a possibly shared anonymous page -- mapped R/O and
not !Page

mm/gup: disallow follow_page(FOLL_PIN)

We want to change the way we handle R/O pins on anonymous pages that might
be shared: if we detect a possibly shared anonymous page -- mapped R/O and
not !PageAnonExclusive() -- we want to trigger unsharing via a page fault,
resulting in an exclusive anonymous page that can be pinned reliably
without getting replaced via COW on the next write fault.

However, the required page fault will be problematic for follow_page(): in
contrast to ordinary GUP, follow_page() doesn't trigger faults internally.
So we would have to end up failing a R/O pin via follow_page(), although
there is something mapped R/O into the page table, which might be rather
surprising.

We don't seem to have follow_page(FOLL_PIN) users, and it's a purely
internal MM function. Let's just make our life easier and the semantics
of follow_page() clearer by just disallowing FOLL_PIN for follow_page()
completely.

Link: https://lkml.kernel.org/r/20220428083441.37290-15-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Liang Zhang <zhangliang5@huawei.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Oded Gabbay <oded.gabbay@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pedro Demarchi Gomes <pedrodemargomes@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...


# da32b581 23-Apr-2022 Catalin Marinas <catalin.marinas@arm.com>

mm: Add fault_in_subpage_writeable() to probe at sub-page granularity

On hardware with features like arm64 MTE or SPARC ADI, an access fault
can be triggered at sub-page granularity. Depending on ho

mm: Add fault_in_subpage_writeable() to probe at sub-page granularity

On hardware with features like arm64 MTE or SPARC ADI, an access fault
can be triggered at sub-page granularity. Depending on how the
fault_in_writeable() function is used, the caller can get into a
live-lock by continuously retrying the fault-in on an address different
from the one where the uaccess failed.

In the majority of cases progress is ensured by the following
conditions:

1. copy_to_user_nofault() guarantees at least one byte access if the
user address is not faulting.

2. The fault_in_writeable() loop is resumed from the first address that
could not be accessed by copy_to_user_nofault().

If the loop iteration is restarted from an earlier (initial) point, the
loop is repeated with the same conditions and it would live-lock.

Introduce an arch-specific probe_subpage_writeable() and call it from
the newly added fault_in_subpage_writeable() function. The arch code
with sub-page faults will have to implement the specific probing
functionality.

Note that no other fault_in_subpage_*() functions are added since they
have no callers currently susceptible to a live-lock.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20220423100751.1870771-2-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

show more ...


# 651a8879 13-Apr-2022 Takashi Iwai <tiwai@suse.de>

Merge branch 'topic/cs35l41' into for-next

Pull CS35L41 codec updates

Signed-off-by: Takashi Iwai <tiwai@suse.de>


# c16c8bfa 12-Apr-2022 Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

Merge drm/drm-next into drm-intel-gt-next

Pull in TTM changes needed for DG2 CCS enabling from Ram.

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>


# 83970cd6 11-Apr-2022 Jani Nikula <jani.nikula@intel.com>

Merge drm/drm-next into drm-intel-next

Sync up with v5.18-rc1, in particular to get 5e3094cfd9fb
("drm/i915/xehpsdv: Add has_flat_ccs to device info").

Signed-off-by: Jani Nikula <jani.nikula@intel

Merge drm/drm-next into drm-intel-next

Sync up with v5.18-rc1, in particular to get 5e3094cfd9fb
("drm/i915/xehpsdv: Add has_flat_ccs to device info").

Signed-off-by: Jani Nikula <jani.nikula@intel.com>

show more ...


# 9cbbd694 05-Apr-2022 Maxime Ripard <maxime@cerno.tech>

Merge drm/drm-next into drm-misc-next

Let's start the 5.19 development cycle.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>


# 230bc2be 02-Mar-2022 Rodrigo Vivi <rodrigo.vivi@intel.com>

Merge drm/drm-next into drm-intel-next

To catch up with recent rounds of pull requests
and get some drm-misc dependencies so we can merge
linux/string_helpers related changes.

Signed-off-by: Rodrig

Merge drm/drm-next into drm-intel-next

To catch up with recent rounds of pull requests
and get some drm-misc dependencies so we can merge
linux/string_helpers related changes.

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

show more ...


# 0aea30a0 19-Apr-2022 Takashi Iwai <tiwai@suse.de>

Merge tag 'asoc-fix-v5.18-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v5.18

A collection of fixes that came in since the merge window, plus

Merge tag 'asoc-fix-v5.18-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v5.18

A collection of fixes that came in since the merge window, plus one new
device ID for an x86 laptop. Nothing that really stands out with
particularly big impact outside of the affected device.

show more ...


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