- Remove unused generic cpuidle support (replaced by PSCI version)
- Fix documentation describing the kernel virtual address space
- Handling of some new CPU errata in Arm implementations
- Rework of our exception table code in preparation for handling
machine checks (i.e. RAS errors) more gracefully
- Switch over to the generic implementation of ioremap()
- Fix lockdep tracking in NMI context
- Instrument our memory barrier macros for KCSAN
- Rework of the kPTI G->nG page-table repainting so that the MMU remains
enabled and the boot time is no longer slowed to a crawl for systems
which require the late remapping
- Enable support for direct swapping of 2MiB transparent huge-pages on
systems without MTE
- Fix handling of MTE tags with allocating new pages with HW KASAN
- Expose the SMIDR register to userspace via sysfs
- Continued rework of the stack unwinder, particularly improving the
behaviour under KASAN
- More repainting of our system register definitions to match the
architectural terminology
- Improvements to the layout of the vDSO objects
- Support for allocating additional bits of HWCAP2 and exposing
FEAT_EBF16 to userspace on CPUs that support it
- Considerable rework and optimisation of our early boot code to reduce
the need for cache maintenance and avoid jumping in and out of the
kernel when handling relocation under KASLR
- Support for disabling SVE and SME support on the kernel command-line
- Support for the Hisilicon HNS3 PMU
- Miscellanous cleanups, trivial updates and minor fixes
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"Highlights include a major rework of our kPTI page-table rewriting
code (which makes it both more maintainable and considerably faster in
the cases where it is required) as well as significant changes to our
early boot code to reduce the need for data cache maintenance and
greatly simplify the KASLR relocation dance.
Summary:
- Remove unused generic cpuidle support (replaced by PSCI version)
- Fix documentation describing the kernel virtual address space
- Handling of some new CPU errata in Arm implementations
- Rework of our exception table code in preparation for handling
machine checks (i.e. RAS errors) more gracefully
- Switch over to the generic implementation of ioremap()
- Fix lockdep tracking in NMI context
- Instrument our memory barrier macros for KCSAN
- Rework of the kPTI G->nG page-table repainting so that the MMU
remains enabled and the boot time is no longer slowed to a crawl
for systems which require the late remapping
- Enable support for direct swapping of 2MiB transparent huge-pages
on systems without MTE
- Fix handling of MTE tags with allocating new pages with HW KASAN
- Expose the SMIDR register to userspace via sysfs
- Continued rework of the stack unwinder, particularly improving the
behaviour under KASAN
- More repainting of our system register definitions to match the
architectural terminology
- Improvements to the layout of the vDSO objects
- Support for allocating additional bits of HWCAP2 and exposing
FEAT_EBF16 to userspace on CPUs that support it
- Considerable rework and optimisation of our early boot code to
reduce the need for cache maintenance and avoid jumping in and out
of the kernel when handling relocation under KASLR
- Support for disabling SVE and SME support on the kernel
command-line
- Support for the Hisilicon HNS3 PMU
- Miscellanous cleanups, trivial updates and minor fixes"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (136 commits)
arm64: Delay initialisation of cpuinfo_arm64::reg_{zcr,smcr}
arm64: fix KASAN_INLINE
arm64/hwcap: Support FEAT_EBF16
arm64/cpufeature: Store elf_hwcaps as a bitmap rather than unsigned long
arm64/hwcap: Document allocation of upper bits of AT_HWCAP
arm64: enable THP_SWAP for arm64
arm64/mm: use GENMASK_ULL for TTBR_BADDR_MASK_52
arm64: errata: Remove AES hwcap for COMPAT tasks
arm64: numa: Don't check node against MAX_NUMNODES
drivers/perf: arm_spe: Fix consistency of SYS_PMSCR_EL1.CX
perf: RISC-V: Add of_node_put() when breaking out of for_each_of_cpu_node()
docs: perf: Include hns3-pmu.rst in toctree to fix 'htmldocs' WARNING
arm64: kasan: Revert "arm64: mte: reset the page tag in page->flags"
mm: kasan: Skip page unpoisoning only if __GFP_SKIP_KASAN_UNPOISON
mm: kasan: Skip unpoisoning of user pages
mm: kasan: Ensure the tags are visible before the tag in page->flags
drivers/perf: hisi: add driver for HNS3 PMU
drivers/perf: hisi: Add description for HNS3 PMU driver
drivers/perf: riscv_pmu_sbi: perf format
perf/arm-cci: Use the bitmap API to allocate bitmaps
...
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Merge tag 'mm-hotfixes-stable-2022-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"Two hotfixes, both cc:stable"
* tag 'mm-hotfixes-stable-2022-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm/hmm: fault non-owner device private entries
page_alloc: fix invalid watermark check on a negative value
If hmm_range_fault() is called with the HMM_PFN_REQ_FAULT flag and a
device private PTE is found, the hmm_range::dev_private_owner page is used
to determine if the device private page should not be faulted in.
However, if the device private page is not owned by the caller,
hmm_range_fault() returns an error instead of calling migrate_to_ram() to
fault in the page.
For example, if a page is migrated to GPU private memory and a RDMA fault
capable NIC tries to read the migrated page, without this patch it will
get an error. With this patch, the page will be migrated back to system
memory and the NIC will be able to read the data.
Link: https://lkml.kernel.org/r/20220727000837.4128709-2-rcampbell@nvidia.com
Link: https://lkml.kernel.org/r/20220725183615.4118795-2-rcampbell@nvidia.com
Fixes: 08ddddda66 ("mm/hmm: check the device private page owner in hmm_range_fault()")
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Reported-by: Felix Kuehling <felix.kuehling@amd.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Cc: Philip Yang <Philip.Yang@amd.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There was a report that a task is waiting at the
throttle_direct_reclaim. The pgscan_direct_throttle in vmstat was
increasing.
This is a bug where zone_watermark_fast returns true even when the free
is very low. The commit f27ce0e140 ("page_alloc: consider highatomic
reserve in watermark fast") changed the watermark fast to consider
highatomic reserve. But it did not handle a negative value case which
can be happened when reserved_highatomic pageblock is bigger than the
actual free.
If watermark is considered as ok for the negative value, allocating
contexts for order-0 will consume all free pages without direct reclaim,
and finally free page may become depleted except highatomic free.
Then allocating contexts may fall into throttle_direct_reclaim. This
symptom may easily happen in a system where wmark min is low and other
reclaimers like kswapd does not make free pages quickly.
Handle the negative case by using MIN.
Link: https://lkml.kernel.org/r/20220725095212.25388-1-jaewon31.kim@samsung.com
Fixes: f27ce0e140 ("page_alloc: consider highatomic reserve in watermark fast")
Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
Reported-by: GyeongHwan Hong <gh21.hong@samsung.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Yong-Taek Lee <ytk.lee@samsung.com>
Cc: <stable@vger.kerenl.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
issues or are too minor to warrant backporting
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Merge tag 'mm-hotfixes-stable-2022-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"Thirteen hotfixes.
Eight are cc:stable and the remainder are for post-5.18 issues or are
too minor to warrant backporting"
* tag 'mm-hotfixes-stable-2022-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mailmap: update Gao Xiang's email addresses
userfaultfd: provide properly masked address for huge-pages
Revert "ocfs2: mount shared volume without ha stack"
hugetlb: fix memoryleak in hugetlb_mcopy_atomic_pte
fs: sendfile handles O_NONBLOCK of out_fd
ntfs: fix use-after-free in ntfs_ucsncmp()
secretmem: fix unhandled fault in truncate
mm/hugetlb: separate path for hwpoison entry in copy_hugetlb_page_range()
mm: fix missing wake-up event for FSDAX pages
mm: fix page leak with multiple threads mapping the same page
mailmap: update Seth Forshee's email address
tmpfs: fix the issue that the mount and remount results are inconsistent.
mm: kfence: apply kmemleak_ignore_phys on early allocated pool
* for-next/mte:
arm64: kasan: Revert "arm64: mte: reset the page tag in page->flags"
mm: kasan: Skip page unpoisoning only if __GFP_SKIP_KASAN_UNPOISON
mm: kasan: Skip unpoisoning of user pages
mm: kasan: Ensure the tags are visible before the tag in page->flags
THP_SWAP has been proven to improve the swap throughput significantly
on x86_64 according to commit bd4c82c22c ("mm, THP, swap: delay
splitting THP after swapped out").
As long as arm64 uses 4K page size, it is quite similar with x86_64
by having 2MB PMD THP. THP_SWAP is architecture-independent, thus,
enabling it on arm64 will benefit arm64 as well.
A corner case is that MTE has an assumption that only base pages
can be swapped. We won't enable THP_SWAP for ARM64 hardware with
MTE support until MTE is reworked to coexist with THP_SWAP.
A micro-benchmark is written to measure thp swapout throughput as
below,
unsigned long long tv_to_ms(struct timeval tv)
{
return tv.tv_sec * 1000 + tv.tv_usec / 1000;
}
main()
{
struct timeval tv_b, tv_e;;
#define SIZE 400*1024*1024
volatile void *p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (!p) {
perror("fail to get memory");
exit(-1);
}
madvise(p, SIZE, MADV_HUGEPAGE);
memset(p, 0x11, SIZE); /* write to get mem */
gettimeofday(&tv_b, NULL);
madvise(p, SIZE, MADV_PAGEOUT);
gettimeofday(&tv_e, NULL);
printf("swp out bandwidth: %ld bytes/ms\n",
SIZE/(tv_to_ms(tv_e) - tv_to_ms(tv_b)));
}
Testing is done on rk3568 64bit Quad Core Cortex-A55 platform -
ROCK 3A.
thp swp throughput w/o patch: 2734bytes/ms (mean of 10 tests)
thp swp throughput w/ patch: 3331bytes/ms (mean of 10 tests)
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Steven Price <steven.price@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Link: https://lore.kernel.org/r/20220720093737.133375-1-21cnbao@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
When alloc_huge_page fails, *pagep is set to NULL without put_page first.
So the hugepage indicated by *pagep is leaked.
Link: https://lkml.kernel.org/r/20220709092629.54291-1-linmiaohe@huawei.com
Fixes: 8cc5fcbb5b ("mm, hugetlb: fix racy resv_huge_pages underflow on UFFDIO_COPY")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Originally copy_hugetlb_page_range() handles migration entries and
hwpoisoned entries in similar manner. But recently the related code path
has more code for migration entries, and when
is_writable_migration_entry() was converted to
!is_readable_migration_entry(), hwpoison entries on source processes got
to be unexpectedly updated (which is legitimate for migration entries, but
not for hwpoison entries). This results in unexpected serious issues like
kernel panic when forking processes with hwpoison entries in pmd.
Separate the if branch into one for hwpoison entries and one for migration
entries.
Link: https://lkml.kernel.org/r/20220704013312.2415700-3-naoya.horiguchi@linux.dev
Fixes: 6c287605fd ("mm: remember exclusively mapped anonymous pages with PG_anon_exclusive")
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: <stable@vger.kernel.org> [5.18]
Cc: David Hildenbrand <david@redhat.com>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
FSDAX page refcounts are 1-based, rather than 0-based: if refcount is
1, then the page is freed. The FSDAX pages can be pinned through GUP,
then they will be unpinned via unpin_user_page() using a folio variant
to put the page, however, folio variants did not consider this special
case, the result will be to miss a wakeup event (like the user of
__fuse_dax_break_layouts()). This results in a task being permanently
stuck in TASK_INTERRUPTIBLE state.
Since FSDAX pages are only possibly obtained by GUP users, so fix GUP
instead of folio_put() to lower overhead.
Link: https://lkml.kernel.org/r/20220705123532.283-1-songmuchun@bytedance.com
Fixes: d8ddc099c6 ("mm/gup: Add gup_put_folio()")
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We have an application with a lot of threads that use a shared mmap backed
by tmpfs mounted with -o huge=within_size. This application started
leaking loads of huge pages when we upgraded to a recent kernel.
Using the page ref tracepoints and a BPF program written by Tejun Heo we
were able to determine that these pages would have multiple refcounts from
the page fault path, but when it came to unmap time we wouldn't drop the
number of refs we had added from the faults.
I wrote a reproducer that mmap'ed a file backed by tmpfs with -o
huge=always, and then spawned 20 threads all looping faulting random
offsets in this map, while using madvise(MADV_DONTNEED) randomly for huge
page aligned ranges. This very quickly reproduced the problem.
The problem here is that we check for the case that we have multiple
threads faulting in a range that was previously unmapped. One thread maps
the PMD, the other thread loses the race and then returns 0. However at
this point we already have the page, and we are no longer putting this
page into the processes address space, and so we leak the page. We
actually did the correct thing prior to f9ce0be71d, however it looks
like Kirill copied what we do in the anonymous page case. In the
anonymous page case we don't yet have a page, so we don't have to drop a
reference on anything. Previously we did the correct thing for file based
faults by returning VM_FAULT_NOPAGE so we correctly drop the reference on
the page we faulted in.
Fix this by returning VM_FAULT_NOPAGE in the pmd_devmap_trans_unstable()
case, this makes us drop the ref on the page properly, and now my
reproducer no longer leaks the huge pages.
[josef@toxicpanda.com: v2]
Link: https://lkml.kernel.org/r/e90c8f0dbae836632b669c2afc434006a00d4a67.1657721478.git.josef@toxicpanda.com
Link: https://lkml.kernel.org/r/2b798acfd95c9ab9395fe85e8d5a835e2e10a920.1657051137.git.josef@toxicpanda.com
Fixes: f9ce0be71d ("mm: Cleanup faultaround and finish_fault() codepaths")
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
An undefined-behavior issue has not been completely fixed since commit
d14f5efadd ("tmpfs: fix undefined-behaviour in shmem_reconfigure()").
In the commit, check in the shmem_reconfigure() is added in remount
process to avoid the Ubsan problem. However, the check is not added to
the mount process. It causes inconsistent results between mount and
remount. The operations to reproduce the problem in user mode as follows:
If nr_blocks is set to 0x8000000000000000, the mounting is successful.
# mount tmpfs /dev/shm/ -t tmpfs -o nr_blocks=0x8000000000000000
However, when -o remount is used, the mount fails because of the
check in the shmem_reconfigure()
# mount tmpfs /dev/shm/ -t tmpfs -o remount,nr_blocks=0x8000000000000000
mount: /dev/shm: mount point not mounted or bad option.
Therefore, add checks in the shmem_parse_one() function and remove the
check in shmem_reconfigure() to avoid this problem.
Link: https://lkml.kernel.org/r/20220629124324.1640807-1-wangzhaolong1@huawei.com
Signed-off-by: ZhaoLong Wang <wangzhaolong1@huawei.com>
Cc: Luo Meng <luomeng12@huawei.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Yu Kuai <yukuai3@huawei.com>
Cc: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This patch solves two issues.
(1) The pool allocated by memblock needs to unregister from
kmemleak scanning. Apply kmemleak_ignore_phys to replace the
original kmemleak_free as its address now is stored in the phys tree.
(2) The pool late allocated by page-alloc doesn't need to unregister.
Move out the freeing operation from its call path.
Link: https://lkml.kernel.org/r/20220628113714.7792-2-yee.lee@mediatek.com
Fixes: 0c24e06119 ("mm: kmemleak: add rbtree and store physical address for objects allocated with PA")
Signed-off-by: Yee Lee <yee.lee@mediatek.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Suggested-by: Marco Elver <elver@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently post_alloc_hook() skips the kasan unpoisoning if the tags will
be zeroed (__GFP_ZEROTAGS) or __GFP_SKIP_KASAN_UNPOISON is passed. Since
__GFP_ZEROTAGS is now accompanied by __GFP_SKIP_KASAN_UNPOISON, remove
the extra check.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20220610152141.2148929-4-catalin.marinas@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Commit c275c5c6d5 ("kasan: disable freed user page poisoning with HW
tags") added __GFP_SKIP_KASAN_POISON to GFP_HIGHUSER_MOVABLE. A similar
argument can be made about unpoisoning, so also add
__GFP_SKIP_KASAN_UNPOISON to user pages. To ensure the user page is
still accessible via page_address() without a kasan fault, reset the
page->flags tag.
With the above changes, there is no need for the arm64
tag_clear_highpage() to reset the page->flags tag.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20220610152141.2148929-3-catalin.marinas@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
__kasan_unpoison_pages() colours the memory with a random tag and stores
it in page->flags in order to re-create the tagged pointer via
page_to_virt() later. When the tag from the page->flags is read, ensure
that the in-memory tags are already visible by re-ordering the
page_kasan_tag_set() after kasan_unpoison(). The former already has
barriers in place through try_cmpxchg(). On the reader side, the order
is ensured by the address dependency between page->flags and the memory
access.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/r/20220610152141.2148929-2-catalin.marinas@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Currently the implementation will split the PUD when a fallback is taken
inside the create_huge_pud function. This isn't where it should be done:
the splitting should be done in wp_huge_pud, just like it's done for PMDs.
Reason being that if a callback is taken during create, there is no PUD
yet so nothing to split, whereas if a fallback is taken when encountering
a write protection fault there is something to split.
It looks like this was the original intention with the commit where the
splitting was introduced, but somehow it got moved to the wrong place
between v1 and v2 of the patch series. Rebase mistake perhaps.
Link: https://lkml.kernel.org/r/6f48d622eb8bce1ae5dd75327b0b73894a2ec407.camel@amazon.com
Fixes: 327e9fd489 ("mm: Split huge pages on write-notify or COW")
Signed-off-by: James Gowans <jgowans@amazon.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Higher order allocations for vmemmap pages from buddy allocator must be
able to be treated as indepdenent small pages as they can be freed
individually by the caller. There is no problem for higher order vmemmap
pages allocated at boot time since each individual small page will be
initialized at boot time. However, it will be an issue for memory hotplug
case since those higher order vmemmap pages are allocated from buddy
allocator without initializing each individual small page's refcount. The
system will panic in put_page_testzero() when CONFIG_DEBUG_VM is enabled
if the vmemmap page is freed.
Link: https://lkml.kernel.org/r/20220620023019.94257-1-songmuchun@bytedance.com
Fixes: d8d55f5616 ("mm: sparsemem: use page table lock to protect kernel pmd operations")
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The huge_ptep_set_access_flags() can not make the huge pte old according
to the discussion [1], that means we will always mornitor the young state
of the hugetlb though we stopped accessing the hugetlb, as a result DAMON
will get inaccurate accessing statistics.
So changing to use set_huge_pte_at() to make the huge pte old to fix this
issue.
[1] https://lore.kernel.org/all/Yqy97gXI4Nqb7dYo@arm.com/
Link: https://lkml.kernel.org/r/1655692482-28797-1-git-send-email-baolin.wang@linux.alibaba.com
Fixes: 49f4203aae ("mm/damon: add access checking for hugetlb pages")
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When fallocate() is used on a shmem file, the pages we allocate can end up
with !PageUptodate.
Since UFFDIO_CONTINUE tries to find the existing page the user wants to
map with SGP_READ, we would fail to find such a page, since
shmem_getpage_gfp returns with a "NULL" pagep for SGP_READ if it discovers
!PageUptodate. As a result, UFFDIO_CONTINUE returns -EFAULT, as it would
do if the page wasn't found in the page cache at all.
This isn't the intended behavior. UFFDIO_CONTINUE is just trying to find
if a page exists, and doesn't care whether it still needs to be cleared or
not. So, instead of SGP_READ, pass in SGP_NOALLOC. This is the same,
except for one critical difference: in the !PageUptodate case, SGP_NOALLOC
will clear the page and then return it. With this change, UFFDIO_CONTINUE
works properly (succeeds) on a shmem file which has been fallocated, but
otherwise not modified.
Link: https://lkml.kernel.org/r/20220610173812.1768919-1-axelrasmussen@google.com
Fixes: 153132571f ("userfaultfd/shmem: support UFFDIO_CONTINUE for shmem")
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Acked-by: Peter Xu <peterx@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add special hook for architecture to verify addr, size or prot
when ioremap() or iounmap(), which will make the generic ioremap
more useful.
ioremap_allowed() return a bool,
- true means continue to remap
- false means skip remap and return directly
iounmap_allowed() return a bool,
- true means continue to vunmap
- false code means skip vunmap and return directly
Meanwhile, only vunmap the address when it is in vmalloc area
as the generic ioremap only returns vmalloc addresses.
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Baoquan He <bhe@redhat.com>
Link: https://lore.kernel.org/r/20220607125027.44946-5-wangkefeng.wang@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Show physical address of each ioremap in /proc/vmallocinfo.
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Link: https://lore.kernel.org/r/20220607125027.44946-4-wangkefeng.wang@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Use more meaningful and sensible naming phys_addr
instead addr in ioremap_prot().
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220610092255.32445-1-wangkefeng.wang@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Fixes for post-5.18 changes:
- fix for a damon boot hang, from SeongJae
- fix for a kfence warning splat, from Jason Donenfeld
- fix for zero-pfn pinning, from Alex Williamson
- fix for fallocate hole punch clearing, from Mike Kravetz
Fixes pre-5.18 material:
- fix for a performance regression, from Marcelo
- fix for a hwpoisining BUG from zhenwei pi
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Merge tag 'mm-hotfixes-stable-2022-06-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull hotfixes from Andrew Morton:
"Minor things, mainly - mailmap updates, MAINTAINERS updates, etc.
Fixes for this merge window:
- fix for a damon boot hang, from SeongJae
- fix for a kfence warning splat, from Jason Donenfeld
- fix for zero-pfn pinning, from Alex Williamson
- fix for fallocate hole punch clearing, from Mike Kravetz
Fixes for previous releases:
- fix for a performance regression, from Marcelo
- fix for a hwpoisining BUG from zhenwei pi"
* tag 'mm-hotfixes-stable-2022-06-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mailmap: add entry for Christian Marangi
mm/memory-failure: disable unpoison once hw error happens
hugetlbfs: zero partial pages during fallocate hole punch
mm: memcontrol: reference to tools/cgroup/memcg_slabinfo.py
mm: re-allow pinning of zero pfns
mm/kfence: select random number before taking raw lock
MAINTAINERS: add maillist information for LoongArch
MAINTAINERS: update MM tree references
MAINTAINERS: update Abel Vesa's email
MAINTAINERS: add MEMORY HOT(UN)PLUG section and add David as reviewer
MAINTAINERS: add Miaohe Lin as a memory-failure reviewer
mailmap: add alias for jarkko@profian.com
mm/damon/reclaim: schedule 'damon_reclaim_timer' only after 'system_wq' is initialized
kthread: make it clear that kthread_create_on_node() might be terminated by any fatal signal
mm: lru_cache_disable: use synchronize_rcu_expedited
mm/page_isolation.c: fix one kernel-doc comment
Commit 793917d997 ("mm/readahead: Add large folio readahead")
introduced support for using large folios for filebacked pages if the
filesystem supports it.
page_cache_ra_order() was introduced to allocate and add these large
folios to the page cache. However adding pages to the page cache should
be serialized against truncation and hole punching by taking
invalidate_lock. Not doing so can lead to data races resulting in stale
data getting added to the page cache and marked up-to-date. See commit
730633f0b7 ("mm: Protect operations adding pages to page cache with
invalidate_lock") for more details.
This issue was found by inspection but a testcase revealed it was
possible to observe in practice on XFS. Fix this by taking
invalidate_lock in page_cache_ra_order(), to mirror what is done for the
non-thp case in page_cache_ra_unbounded().
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Fixes: 793917d997 ("mm/readahead: Add large folio readahead")
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
In our efforts to remove uses of PG_private, we have found folios with
the private flag clear and folio->private not-NULL. That is the root
cause behind 642d51fb07 ("ceph: check folio PG_private bit instead
of folio->private"). It can also affect a few other filesystems that
haven't yet reported a problem.
compaction_alloc() can return a page with uninitialised page->private,
and rather than checking all the callers of migrate_pages(), just zero
page->private after calling get_new_page(). Similarly, the tail pages
from split_huge_page() may also have an uninitialised page->private.
Reported-by: Xiubo Li <xiubli@redhat.com>
Tested-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
If a read races with an invalidation followed by another read, it is
possible for a folio to be replaced with a higher-order folio. If that
happens, we'll see a sibling entry for the new folio in the next iteration
of the loop. This manifests as a NULL pointer dereference while holding
the RCU read lock.
Handle this by simply returning. The next call will find the new folio
and handle it correctly. The other ways of handling this rare race are
more complex and it's just not worth it.
Reported-by: Dave Chinner <david@fromorbit.com>
Reported-by: Brian Foster <bfoster@redhat.com>
Debugged-by: Brian Foster <bfoster@redhat.com>
Tested-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Fixes: cbd59c48ae ("mm/filemap: use head pages in generic_file_buffered_read")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
We had an off-by-one error which meant that we never marked the first page
in a read as accessed. This was visible as a slowdown when re-reading
a file as pages were being evicted from cache too soon. In reviewing
this code, we noticed a second bug where a multi-page folio would be
marked as accessed multiple times when doing reads that were less than
the size of the folio.
Abstract the comparison of whether two file positions are in the same
folio into a new function, fixing both of these bugs.
Reported-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
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Merge tag 'slab-for-5.19-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab fixes from Vlastimil Babka:
- A slub fix for PREEMPT_RT locking semantics from Sebastian.
- A slub fix for state corruption due to a possible race scenario from
Jann.
* tag 'slab-for-5.19-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
mm/slub: add missing TID updates on slab deactivation
mm/slub: Move the stackdepot related allocation out of IRQ-off section.
Pull writeback and ext2 fixes from Jan Kara:
"A fix for writeback bug which prevented machines with kdevtmpfs from
booting and also one small ext2 bugfix in IO error handling"
* tag 'fs_for_v5.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
init: Initialize noop_backing_dev_info early
ext2: fix fs corruption when trying to remove a non-empty directory with IO error
There is no slabinfo.py in tools/cgroup, but has memcg_slabinfo.py instead.
Link: https://lkml.kernel.org/r/20220610024451.744135-1-yang.yang29@zte.com.cn
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The RNG uses vanilla spinlocks, not raw spinlocks, so kfence should pick
its random numbers before taking its raw spinlocks. This also has the
nice effect of doing less work inside the lock. It should fix a splat
that Geert saw with CONFIG_PROVE_RAW_LOCK_NESTING:
dump_backtrace.part.0+0x98/0xc0
show_stack+0x14/0x28
dump_stack_lvl+0xac/0xec
dump_stack+0x14/0x2c
__lock_acquire+0x388/0x10a0
lock_acquire+0x190/0x2c0
_raw_spin_lock_irqsave+0x6c/0x94
crng_make_state+0x148/0x1e4
_get_random_bytes.part.0+0x4c/0xe8
get_random_u32+0x4c/0x140
__kfence_alloc+0x460/0x5c4
kmem_cache_alloc_trace+0x194/0x1dc
__kthread_create_on_node+0x5c/0x1a8
kthread_create_on_node+0x58/0x7c
printk_start_kthread.part.0+0x34/0xa8
printk_activate_kthreads+0x4c/0x54
do_one_initcall+0xec/0x278
kernel_init_freeable+0x11c/0x214
kernel_init+0x24/0x124
ret_from_fork+0x10/0x20
Link: https://lkml.kernel.org/r/20220609123319.17576-1-Jason@zx2c4.com
Fixes: d4150779e6 ("random32: use real rng for non-deterministic randomness")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Commit 059342d1dd ("mm/damon/reclaim: fix the timer always stays
active") made DAMON_RECLAIM's 'enabled' parameter store callback,
'enabled_store()', to schedule 'damon_reclaim_timer'. The scheduling uses
'system_wq', which is initialized in 'workqueue_init_early()'. As kernel
parameters parsing function ('parse_args()') is called before
'workqueue_init_early()', 'enabled_store()' can be executed before
'workqueue_init_early()' and end up accessing the uninitialized
'system_wq'. As a result, the booting hang[1]. This commit fixes the
issue by checking if the initialization is done before scheduling the
timer.
[1] https://lkml.kernel.org/20220604192222.1488-1-sj@kernel.org/
Link: https://lkml.kernel.org/r/20220604195051.1589-1-sj@kernel.org
Fixes: 059342d1dd ("mm/damon/reclaim: fix the timer always stays active")
Signed-off-by: SeongJae Park <sj@kernel.org>
Reported-by: Greg White <gwhite@kupulau.com>
Cc: Hailong Tu <tuhailong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
commit ff042f4a9b ("mm: lru_cache_disable: replace work queue
synchronization with synchronize_rcu") replaced lru_cache_disable's usage
of work queues with synchronize_rcu.
Some users reported large performance regressions due to this commit, for
example:
https://lore.kernel.org/all/20220521234616.GO1790663@paulmck-ThinkPad-P17-Gen-1/T/
Switching to synchronize_rcu_expedited fixes the problem.
Link: https://lkml.kernel.org/r/YpToHCmnx/HEcVyR@fuller.cnet
Fixes: ff042f4a9b ("mm: lru_cache_disable: replace work queue synchronization with synchronize_rcu")
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Tested-by: Michael Larabel <Michael@MichaelLarabel.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Phil Elwell <phil@raspberrypi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove one warning found by running scripts/kernel-doc, which is caused by
using 'make W=1':
mm/page_isolation.c:304: warning: Function parameter or member
'skip_isolation' not described in 'isolate_single_pageblock'
Link: https://lkml.kernel.org/r/20220602062116.61199-1-yang.lee@linux.alibaba.com
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
noop_backing_dev_info is used by superblocks of various
pseudofilesystems such as kdevtmpfs. After commit 10e1407310
("writeback: Fix inode->i_io_list not be protected by inode->i_lock
error") this broke because __mark_inode_dirty() started to access more
fields from noop_backing_dev_info and this led to crashes inside
locked_inode_to_wb_and_lock_list() called from __mark_inode_dirty().
Fix the problem by initializing noop_backing_dev_info before the
filesystems get mounted.
Fixes: 10e1407310 ("writeback: Fix inode->i_io_list not be protected by inode->i_lock error")
Reported-and-tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reported-and-tested-by: Alexandru Elisei <alexandru.elisei@arm.com>
Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
If 'n' is so large that it's negative, we might wrap around and mistakenly
think that the copy is OK when it's not. Such a copy would probably
crash, but just doing the arithmetic in a more simple way lets us detect
and refuse this case.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Tested-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220612213227.3881769-4-willy@infradead.org
Get rid of a lot of annoying casts by setting 'addr' once at the top
of the function.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Tested-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220612213227.3881769-3-willy@infradead.org
vmalloc does not allocate a vm_struct for vm_map_ram() areas. That causes
us to deny usercopies from those areas. This affects XFS which uses
vm_map_ram() for its directories.
Fix this by calling find_vmap_area() instead of find_vm_area().
Fixes: 0aef499f31 ("mm/usercopy: Detect vmalloc overruns")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Tested-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220612213227.3881769-2-willy@infradead.org
The fastpath in slab_alloc_node() assumes that c->slab is stable as long as
the TID stays the same. However, two places in __slab_alloc() currently
don't update the TID when deactivating the CPU slab.
If multiple operations race the right way, this could lead to an object
getting lost; or, in an even more unlikely situation, it could even lead to
an object being freed onto the wrong slab's freelist, messing up the
`inuse` counter and eventually causing a page to be freed to the page
allocator while it still contains slab objects.
(I haven't actually tested these cases though, this is just based on
looking at the code. Writing testcases for this stuff seems like it'd be
a pain...)
The race leading to state inconsistency is (all operations on the same CPU
and kmem_cache):
- task A: begin do_slab_free():
- read TID
- read pcpu freelist (==NULL)
- check `slab == c->slab` (true)
- [PREEMPT A->B]
- task B: begin slab_alloc_node():
- fastpath fails (`c->freelist` is NULL)
- enter __slab_alloc()
- slub_get_cpu_ptr() (disables preemption)
- enter ___slab_alloc()
- take local_lock_irqsave()
- read c->freelist as NULL
- get_freelist() returns NULL
- write `c->slab = NULL`
- drop local_unlock_irqrestore()
- goto new_slab
- slub_percpu_partial() is NULL
- get_partial() returns NULL
- slub_put_cpu_ptr() (enables preemption)
- [PREEMPT B->A]
- task A: finish do_slab_free():
- this_cpu_cmpxchg_double() succeeds()
- [CORRUPT STATE: c->slab==NULL, c->freelist!=NULL]
From there, the object on c->freelist will get lost if task B is allowed to
continue from here: It will proceed to the retry_load_slab label,
set c->slab, then jump to load_freelist, which clobbers c->freelist.
But if we instead continue as follows, we get worse corruption:
- task A: run __slab_free() on object from other struct slab:
- CPU_PARTIAL_FREE case (slab was on no list, is now on pcpu partial)
- task A: run slab_alloc_node() with NUMA node constraint:
- fastpath fails (c->slab is NULL)
- call __slab_alloc()
- slub_get_cpu_ptr() (disables preemption)
- enter ___slab_alloc()
- c->slab is NULL: goto new_slab
- slub_percpu_partial() is non-NULL
- set c->slab to slub_percpu_partial(c)
- [CORRUPT STATE: c->slab points to slab-1, c->freelist has objects
from slab-2]
- goto redo
- node_match() fails
- goto deactivate_slab
- existing c->freelist is passed into deactivate_slab()
- inuse count of slab-1 is decremented to account for object from
slab-2
At this point, the inuse count of slab-1 is 1 lower than it should be.
This means that if we free all allocated objects in slab-1 except for one,
SLUB will think that slab-1 is completely unused, and may free its page,
leading to use-after-free.
Fixes: c17dda40a6 ("slub: Separate out kmem_cache_cpu processing from deactivate_slab")
Fixes: 03e404af26 ("slub: fast release on full slab")
Cc: stable@vger.kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Link: https://lore.kernel.org/r/20220608182205.2945720-1-jannh@google.com
The set_track() invocation in free_debug_processing() is invoked with
acquired slab_lock(). The lock disables interrupts on PREEMPT_RT and
this forbids to allocate memory which is done in stack_depot_save().
Split set_track() into two parts: set_track_prepare() which allocate
memory and set_track_update() which only performs the assignment of the
trace data structure. Use set_track_prepare() before disabling
interrupts.
[ vbabka@suse.cz: make set_track() call set_track_update() instead of
open-coded assignments ]
Fixes: 5cf909c553 ("mm/slub: use stackdepot to save stack trace in objects")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Link: https://lore.kernel.org/r/Yp9sqoUi4fVa5ExF@linutronix.de
If xas_split_alloc() fails to allocate the necessary nodes to complete the
xarray entry split, it sets the xa_state to -ENOMEM, which xas_nomem()
then interprets as "Please allocate more memory", not as "Please free
any unnecessary memory" (which was the intended outcome). It's confusing
to use xas_nomem() to free memory in this context, so call xas_destroy()
instead.
Reported-by: syzbot+9e27a75a8c24f3fe75c1@syzkaller.appspotmail.com
Fixes: 6b24ca4a1a ("mm: Use multi-index entries in the page cache")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
After we have unlocked the mmap_lock for I/O, the file is pinned, but
the VMA is not. Checking this flag after that can be a use-after-free.
It's not a terribly interesting use-after-free as it can only read one
bit, and it's used to decide whether to read 2MB or 4MB. But it
upsets the automated tools and it's generally bad practice anyway,
so let's fix it.
Reported-by: syzbot+5b96d55e5b54924c77ad@syzkaller.appspotmail.com
Fixes: 4687fdbb80 ("mm/filemap: Support VM_HUGEPAGE for file mappings")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
We must hold a reference over the call to filemap_release_folio(),
otherwise the page cache will put the last reference to the folio
before we unlock it, leading to splats like this:
BUG: Bad page state in process u8:5 pfn:1ab1f4
page:ffffea0006ac7d00 refcount:0 mapcount:0 mapping:0000000000000000 index:0x28b1de pfn:0x1ab1f4
flags: 0x17ff80000040001(locked|reclaim|node=0|zone=2|lastcpupid=0xfff)
raw: 017ff80000040001 dead000000000100 dead000000000122 0000000000000000
raw: 000000000028b1de 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
It's an error path, so it doesn't see much testing.
Reported-by: Darrick J. Wong <djwong@kernel.org>
Fixes: a42634a6c0 ("readahead: Use a folio in read_pages()")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
- fixes for material merged during this merge window
- cc:stable fixes for more longstanding issues
- minor mailmap and MAINTAINERS updates
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Merge tag 'mm-hotfixes-stable-2022-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull mm hotfixes from Andrew Morton:
"Fixups for various recently-added and longer-term issues and a few
minor tweaks:
- fixes for material merged during this merge window
- cc:stable fixes for more longstanding issues
- minor mailmap and MAINTAINERS updates"
* tag 'mm-hotfixes-stable-2022-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm/oom_kill.c: fix vm_oom_kill_table[] ifdeffery
x86/kexec: fix memory leak of elf header buffer
mm/memremap: fix missing call to untrack_pfn() in pagemap_range()
mm: page_isolation: use compound_nr() correctly in isolate_single_pageblock()
mm: hugetlb_vmemmap: fix CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON
MAINTAINERS: add maintainer information for z3fold
mailmap: update Josh Poimboeuf's email
