commit d9da8f6cf5 upstream.
Add a clear_highpage_kasan_tagged() helper that does clear_highpage() on a
page potentially tagged by KASAN.
This helper is used by the following patch.
Link: https://lkml.kernel.org/r/4471979b46b2c487787ddcd08b9dc5fedd1b6ffd.1654798516.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2727cfe407 ]
We forget to set cft->private for numa stat file. As a result, numa stat
of hstates[0] is always showed for all hstates. Encode the hstates index
into cft->private to fix this issue.
Link: https://lkml.kernel.org/r/20220723073804.53035-1-linmiaohe@huawei.com
Fixes: f477619990 ("hugetlb: add hugetlb.*.numa_stat file")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 188043c7f4 ]
damon_reclaim_init() allocates a memory chunk for ctx with
damon_new_ctx(). When damon_select_ops() fails, ctx is not released,
which will lead to a memory leak.
We should release the ctx with damon_destroy_ctx() when damon_select_ops()
fails to fix the memory leak.
Link: https://lkml.kernel.org/r/20220714063746.2343549-1-niejianglei2021@163.com
Fixes: 4d69c34578 ("mm/damon/reclaim: use damon_select_ops() instead of damon_{v,p}a_set_operations()")
Signed-off-by: Jianglei Nie <niejianglei2021@163.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7f82f92231 ]
Since the beginning, charged is set to 0 to avoid calling vm_unacct_memory
twice because vm_unacct_memory will be called by above unmap_region. But
since commit 4f74d2c8e8 ("vm: remove 'nr_accounted' calculations from
the unmap_vmas() interfaces"), unmap_region doesn't call vm_unacct_memory
anymore. So charged shouldn't be set to 0 now otherwise the calling to
paired vm_unacct_memory will be missed and leads to imbalanced account.
Link: https://lkml.kernel.org/r/20220618082027.43391-1-linmiaohe@huawei.com
Fixes: 4f74d2c8e8 ("vm: remove 'nr_accounted' calculations from the unmap_vmas() interfaces")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 000eca5d04 ]
When user specified more nodes than supported, get_nodes will access nmask
array out of bounds.
Link: https://lkml.kernel.org/r/20220601093211.2970565-1-tianyu.li@arm.com
Fixes: e130242dc3 ("mm: simplify compat numa syscalls")
Signed-off-by: Tianyu Li <tianyu.li@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6c2f761dad ]
HW_TAGS KASAN skips zeroing page_alloc allocations backing vmalloc
mappings via __GFP_SKIP_ZERO. Instead, these pages are zeroed via
kasan_unpoison_vmalloc() by passing the KASAN_VMALLOC_INIT flag.
The problem is that __kasan_unpoison_vmalloc() does not zero pages when
either kasan_vmalloc_enabled() or is_vmalloc_or_module_addr() fail.
Thus:
1. Change __vmalloc_node_range() to only set KASAN_VMALLOC_INIT when
__GFP_SKIP_ZERO is set.
2. Change __kasan_unpoison_vmalloc() to always zero pages when the
KASAN_VMALLOC_INIT flag is set.
3. Add WARN_ON() asserts to check that KASAN_VMALLOC_INIT cannot be set
in other early return paths of __kasan_unpoison_vmalloc().
Also clean up the comment in __kasan_unpoison_vmalloc.
Link: https://lkml.kernel.org/r/4bc503537efdc539ffc3f461c1b70162eea31cf6.1654798516.git.andreyknvl@google.com
Fixes: 23689e91fb ("kasan, vmalloc: add vmalloc tagging for HW_TAGS")
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ad1ac596e8 ]
__migration_entry_wait and migration_entry_wait_on_locked assume pte is
always mapped from caller. But this is not the case when it's called from
migration_entry_wait_huge and follow_huge_pmd. Add a hugetlbfs variant
that calls hugetlb_migration_entry_wait(ptep == NULL) to fix this issue.
Link: https://lkml.kernel.org/r/20220530113016.16663-5-linmiaohe@huawei.com
Fixes: 30dad30922 ("mm: migration: add migrate_entry_wait_huge()")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: kernel test robot <lkp@intel.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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7ce82f4c3f ]
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: e8db67eb0d ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1e57ffb6e3 ]
Think about the below scene:
CPU1 CPU2
memunmap_pages
percpu_ref_exit
__percpu_ref_exit
free_percpu(percpu_count);
/* percpu_count is freed here! */
get_dev_pagemap
xa_load(&pgmap_array, PHYS_PFN(phys))
/* pgmap still in the pgmap_array */
percpu_ref_tryget_live(&pgmap->ref)
if __ref_is_percpu
/* __PERCPU_REF_ATOMIC_DEAD not set yet */
this_cpu_inc(*percpu_count)
/* access freed percpu_count here! */
ref->percpu_count_ptr = __PERCPU_REF_ATOMIC_DEAD;
/* too late... */
pageunmap_range
To fix the issue, do percpu_ref_exit() after pgmap_array is emptied. So
we won't do percpu_ref_tryget_live() against a being freed percpu_ref.
Link: https://lkml.kernel.org/r/20220609121305.2508-1-linmiaohe@huawei.com
Fixes: b7b3c01b19 ("mm/memremap_pages: support multiple ranges per invocation")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fb5c2029f8 ]
If the last folio in a file is split as a result of truncation,
we simply clear the dirty bits for the pages we're discarding.
That causes NR_FILE_DIRTY (among other counters) to be thrown off
and eventually Linux will hang in balance_dirty_pages_ratelimited()
Reported-by: Dave Chinner <dchinner@redhat.com>
Tested-by: Dave Chinner <dchinner@redhat.com>
Tested-by: Darrick J. Wong <djwong@kernel.org>
Fixes: d68eccad37 ("mm/filemap: Allow large folios to be added to the page cache")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 9282012fc0 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8a295dbbaf upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit da9a298f5f upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f4f451a16d upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3fe2895cfe upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ed1523a895 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 14c99d6594 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 39d35edee4 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 73f37dbcfe upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3173346337 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 00fa15e0d5 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit eeaa345e12 upstream.
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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cb995f4eeb upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4bca7e80b6 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 69a37a8ba1 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dcfa24ba68 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a04e1928e2 upstream.
We forget to call untrack_pfn() to pair with track_pfn_remap() when range
is not allowed to hotplug. Fix it by jump err_kasan.
Link: https://lkml.kernel.org/r/20220531122643.25249-1-linmiaohe@huawei.com
Fixes: bca3feaa07 ("mm/memory_hotplug: prevalidate the address range being added with platform")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 48381273f8 upstream.
The routine huge_pmd_unshare() is passed a pointer to an address
associated with an area which may be unshared. If unshare is successful
this address is updated to 'optimize' callers iterating over huge page
addresses. For the optimization to work correctly, address should be
updated to the last huge page in the unmapped/unshared area. However, in
the common case where the passed address is PUD_SIZE aligned, the address
is incorrectly updated to the address of the preceding huge page. That
wastes CPU cycles as the unmapped/unshared range is scanned twice.
Link: https://lkml.kernel.org/r/20220524205003.126184-1-mike.kravetz@oracle.com
Fixes: 39dde65c99 ("shared page table for hugetlb page")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c572e4888a upstream.
Peter Pavlisko reported the following problem on kernel bugzilla 216007.
When I try to extract an uncompressed tar archive (2.6 milion
files, 760.3 GiB in size) on newly created (empty) XFS file system,
after first low tens of gigabytes extracted the process hangs in
iowait indefinitely. One CPU core is 100% occupied with iowait,
the other CPU core is idle (on 2-core Intel Celeron G1610T).
It was bisected to c9fa563072 ("xfs: use alloc_pages_bulk_array() for
buffers") but XFS is only the messenger. The problem is that nothing is
waking kswapd to reclaim some pages at a time the PCP lists cannot be
refilled until some reclaim happens. The bulk allocator checks that there
are some pages in the array and the original intent was that a bulk
allocator did not necessarily need all the requested pages and it was best
to return as quickly as possible.
This was fine for the first user of the API but both NFS and XFS require
the requested number of pages be available before making progress. Both
could be adjusted to call the page allocator directly if a bulk allocation
fails but it puts a burden on users of the API. Adjust the semantics to
attempt at least one allocation via __alloc_pages() before returning so
kswapd is woken if necessary.
It was reported via bugzilla that the patch addressed the problem and that
the tar extraction completed successfully. This may also address bug
215975 but has yet to be confirmed.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=216007
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215975
Link: https://lkml.kernel.org/r/20220526091210.GC3441@techsingularity.net
Fixes: 387ba26fb1 ("mm/page_alloc: add a bulk page allocator")
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: <stable@vger.kernel.org> [5.13+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 60a60e32cf upstream.
This reverts commit a4efc174b3 which introduced a regression issue
that when there're multiple processes allocating dma memory in parallel by
calling dma_alloc_coherent(), it may fail sometimes as follows:
Error log:
cma: cma_alloc: linux,cma: alloc failed, req-size: 148 pages, ret: -16
cma: number of available pages:
3@125+20@172+12@236+4@380+32@736+17@2287+23@2473+20@36076+99@40477+108@40852+44@41108+20@41196+108@41364+108@41620+
108@42900+108@43156+483@44061+1763@45341+1440@47712+20@49324+20@49388+5076@49452+2304@55040+35@58141+20@58220+20@58284+
7188@58348+84@66220+7276@66452+227@74525+6371@75549=> 33161 free of 81920 total pages
When issue happened, we saw there were still 33161 pages (129M) free CMA
memory and a lot available free slots for 148 pages in CMA bitmap that we
want to allocate.
When dumping memory info, we found that there was also ~342M normal
memory, but only 1352K CMA memory left in buddy system while a lot of
pageblocks were isolated.
Memory info log:
Normal free:351096kB min:30000kB low:37500kB high:45000kB reserved_highatomic:0KB
active_anon:98060kB inactive_anon:98948kB active_file:60864kB inactive_file:31776kB
unevictable:0kB writepending:0kB present:1048576kB managed:1018328kB mlocked:0kB
bounce:0kB free_pcp:220kB local_pcp:192kB free_cma:1352kB lowmem_reserve[]: 0 0 0
Normal: 78*4kB (UECI) 1772*8kB (UMECI) 1335*16kB (UMECI) 360*32kB (UMECI) 65*64kB (UMCI)
36*128kB (UMECI) 16*256kB (UMCI) 6*512kB (EI) 8*1024kB (UEI) 4*2048kB (MI) 8*4096kB (EI)
8*8192kB (UI) 3*16384kB (EI) 8*32768kB (M) = 489288kB
The root cause of this issue is that since commit a4efc174b3 ("mm/cma.c:
remove redundant cma_mutex lock"), CMA supports concurrent memory
allocation. It's possible that the memory range process A trying to alloc
has already been isolated by the allocation of process B during memory
migration.
The problem here is that the memory range isolated during one allocation
by start_isolate_page_range() could be much bigger than the real size we
want to alloc due to the range is aligned to MAX_ORDER_NR_PAGES.
Taking an ARMv7 platform with 1G memory as an example, when
MAX_ORDER_NR_PAGES is big (e.g. 32M with max_order 14) and CMA memory is
relatively small (e.g. 128M), there're only 4 MAX_ORDER slot, then it's
very easy that all CMA memory may have already been isolated by other
processes when one trying to allocate memory using dma_alloc_coherent().
Since current CMA code will only scan one time of whole available CMA
memory, then dma_alloc_coherent() may easy fail due to contention with
other processes.
This patch simply falls back to the original method that using cma_mutex
to make alloc_contig_range() run sequentially to avoid the issue.
Link: https://lkml.kernel.org/r/20220509094551.3596244-1-aisheng.dong@nxp.com
Link: https://lore.kernel.org/all/20220315144521.3810298-2-aisheng.dong@nxp.com/
Fixes: a4efc174b3 ("mm/cma.c: remove redundant cma_mutex lock")
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org> [5.11+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bbe832b9db upstream.
At present, pages not in the target zone are added to cc->migratepages
list in isolate_migratepages_block(). As a result, pages may migrate
between nodes unintentionally.
This would be a serious problem for older kernels without commit
a984226f45 ("mm: memcontrol: remove the pgdata parameter of
mem_cgroup_page_lruvec"), because it can corrupt the lru list by
handling pages in list without holding proper lru_lock.
Avoid returning a pfn outside the target zone in the case that it is
not aligned with a pageblock boundary. Otherwise
isolate_migratepages_block() will handle pages not in the target zone.
Link: https://lkml.kernel.org/r/20220511044300.4069-1-yamamoto.rei@jp.fujitsu.com
Fixes: 70b44595ea ("mm, compaction: use free lists to quickly locate a migration source")
Signed-off-by: Rei Yamamoto <yamamoto.rei@jp.fujitsu.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Wonhyuk Yang <vvghjk1234@gmail.com>
Cc: Rei Yamamoto <yamamoto.rei@jp.fujitsu.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2505a98111 upstream.
The asynchronous zspage free worker tries to lock a zspage's entire page
list without defending against page migration. Since pages which haven't
yet been locked can concurrently migrate off the zspage page list while
lock_zspage() churns away, lock_zspage() can suffer from a few different
lethal races.
It can lock a page which no longer belongs to the zspage and unsafely
dereference page_private(), it can unsafely dereference a torn pointer to
the next page (since there's a data race), and it can observe a spurious
NULL pointer to the next page and thus not lock all of the zspage's pages
(since a single page migration will reconstruct the entire page list, and
create_page_chain() unconditionally zeroes out each list pointer in the
process).
Fix the races by using migrate_read_lock() in lock_zspage() to synchronize
with page migration.
Link: https://lkml.kernel.org/r/20220509024703.243847-1-sultan@kerneltoast.com
Fixes: 77ff465799 ("zsmalloc: zs_page_migrate: skip unnecessary loops but not return -EBUSY if zspage is not inuse")
Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5ad7dd882e upstream.
randomize_page is an mm function. It is documented like one. It contains
the history of one. It has the naming convention of one. It looks
just like another very similar function in mm, randomize_stack_top().
And it has always been maintained and updated by mm people. There is no
need for it to be in random.c. In the "which shape does not look like
the other ones" test, pointing to randomize_page() is correct.
So move randomize_page() into mm/util.c, right next to the similar
randomize_stack_top() function.
This commit contains no actual code changes.
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'mm-hotfixes-stable-2022-05-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"Seven MM fixes, three of which address issues added in the most recent
merge window, four of which are cc:stable.
Three non-MM fixes, none very serious"
[ And yes, that's a real pull request from Andrew, not me creating a
branch from emailed patches. Woo-hoo! ]
* tag 'mm-hotfixes-stable-2022-05-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
MAINTAINERS: add a mailing list for DAMON development
selftests: vm: Makefile: rename TARGETS to VMTARGETS
mm/kfence: reset PG_slab and memcg_data before freeing __kfence_pool
mailmap: add entry for martyna.szapar-mudlaw@intel.com
arm[64]/memremap: don't abuse pfn_valid() to ensure presence of linear map
procfs: prevent unprivileged processes accessing fdinfo dir
mm: mremap: fix sign for EFAULT error return value
mm/hwpoison: use pr_err() instead of dump_page() in get_any_page()
mm/huge_memory: do not overkill when splitting huge_zero_page
Revert "mm/memory-failure.c: skip huge_zero_page in memory_failure()"
The mremap syscall is supposed to return a pointer to the new virtual
memory area on success, and a negative value of the error code in case of
failure. Currently, EFAULT is returned when the VMA is not found, instead
of -EFAULT. The users of this syscall will therefore believe the syscall
succeeded in case the VMA didn't exist, as it returns a pointer to address
0xe (0xe being the value of EFAULT). Fix the sign of the error value.
Link: https://lkml.kernel.org/r/20220427224439.23828-2-dossche.niels@gmail.com
Fixes: 550a7d60bd ("mm, hugepages: add mremap() support for hugepage backed vma")
Signed-off-by: Niels Dossche <dossche.niels@gmail.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reading 100KB chunks from a big file (eg dd bs=100K) leads to poor
readahead behaviour. Studying the traces in detail, I noticed two
problems.
The first is that we were setting the readahead flag on the folio which
contains the last byte read from the block. This is wrong because we
will trigger readahead at the end of the read without waiting to see
if a subsequent read is going to use the pages we just read. Instead,
we need to set the readahead flag on the first folio _after_ the one
which contains the last byte that we're reading.
The second is that we were looking for the index of the folio with the
readahead flag set to exactly match the start + size - async_size.
If we've rounded this, either down (as previously) or up (as now),
we'll think we hit a folio marked as readahead by a different read,
and try to read the wrong pages. So round the expected index to the
order of the folio we hit.
Reported-by: Guo Xuenan <guoxuenan@huawei.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Patch series "mm/memory-failure: rework fix on huge_zero_page splitting".
This patch (of 2):
This reverts commit d173d5417f.
The commit d173d5417f ("mm/memory-failure.c: skip huge_zero_page in
memory_failure()") explicitly skips huge_zero_page in memory_failure(), in
order to avoid triggering VM_BUG_ON_PAGE on huge_zero_page in
split_huge_page_to_list().
This works, but Yang Shi thinks that,
Raising BUG is overkilling for splitting huge_zero_page. The
huge_zero_page can't be met from normal paths other than memory
failure, but memory failure is a valid caller. So I tend to replace
the BUG to WARN + returning -EBUSY. If we don't care about the
reason code in memory failure, we don't have to touch memory
failure.
And for the issue that huge_zero_page will be set PG_has_hwpoisoned,
Yang Shi comments that,
The anonymous page fault doesn't check if the page is poisoned or
not since it typically gets a fresh allocated page and assumes the
poisoned page (isolated successfully) can't be reallocated again.
But huge zero page and base zero page are reused every time. So no
matter what fix we pick, the issue is always there.
Finally, Yang, David, Anshuman and Naoya all agree to fix the bug, i.e.,
to split huge_zero_page, in split_huge_page_to_list().
This reverts the commit d173d5417f ("mm/memory-failure.c: skip
huge_zero_page in memory_failure()"), and the original bug will be fixed
by the next patch.
Link: https://lkml.kernel.org/r/872cefb182ba1dd686b0e7db1e6b2ebe5a4fff87.1651039624.git.xuyu@linux.alibaba.com
Fixes: d173d5417f ("mm/memory-failure.c: skip huge_zero_page in memory_failure()")
Fixes: 6a46079cf5 ("HWPOISON: The high level memory error handler in the VM v7")
Signed-off-by: Xu Yu <xuyu@linux.alibaba.com>
Suggested-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
kasan_quarantine_remove_cache() is called in kmem_cache_shrink()/
destroy(). The kasan_quarantine_remove_cache() call is protected by
cpuslock in kmem_cache_destroy() to ensure serialization with
kasan_cpu_offline().
However the kasan_quarantine_remove_cache() call is not protected by
cpuslock in kmem_cache_shrink(). When a CPU is going offline and cache
shrink occurs at same time, the cpu_quarantine may be corrupted by
interrupt (per_cpu_remove_cache operation).
So add a cpu_quarantine offline flags check in per_cpu_remove_cache().
[akpm@linux-foundation.org: add comment, per Zqiang]
Link: https://lkml.kernel.org/r/20220414025925.2423818-1-qiang1.zhang@intel.com
Signed-off-by: Zqiang <qiang1.zhang@intel.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit 559089e0a9 ("vmalloc: replace VM_NO_HUGE_VMAP with
VM_ALLOW_HUGE_VMAP"), the use of hugepage mappings for vmalloc is an
opt-in strategy, because it caused a number of problems that weren't
noticed until x86 enabled it too.
One of the issues was fixed by Nick Piggin in commit 3b8000ae18
("mm/vmalloc: huge vmalloc backing pages should be split rather than
compound"), but I'm still worried about page protection issues, and
VM_FLUSH_RESET_PERMS in particular.
However, like the hash table allocation case (commit f2edd118d02d:
"page_alloc: use vmalloc_huge for large system hash"), the use of
kvmalloc() should be safe from any such games, since the returned
pointer might be a SLUB allocation, and as such no user should
reasonably be using it in any odd ways.
We also know that the allocations are fairly large, since it falls back
to the vmalloc case only when a kmalloc() fails. So using a hugepage
mapping seems both safe and relevant.
This patch does show a weakness in the opt-in strategy: since the opt-in
flag is in the 'vm_flags', not the usual gfp_t allocation flags, very
few of the usual interfaces actually expose it.
That's not much of an issue in this case that already used one of the
fairly specialized low-level vmalloc interfaces for the allocation, but
for a lot of other vmalloc() users that might want to opt in, it's going
to be very inconvenient.
We'll either have to fix any compatibility problems, or expose it in the
gfp flags (__GFP_COMP would have made a lot of sense) to allow normal
vmalloc() users to use hugepage mappings. That said, the cases that
really matter were probably already taken care of by the hash tabel
allocation.
Link: https://lore.kernel.org/all/20220415164413.2727220-1-song@kernel.org/
Link: https://lore.kernel.org/all/CAHk-=whao=iosX1s5Z4SF-ZGa-ebAukJoAdUJFk5SPwnofV+Vg@mail.gmail.com/
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Menzel <pmenzel@molgen.mpg.de>
Cc: Song Liu <songliubraving@fb.com>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use vmalloc_huge() in alloc_large_system_hash() so that large system
hash (>= PMD_SIZE) could benefit from huge pages.
Note that vmalloc_huge only allocates huge pages for systems with
HAVE_ARCH_HUGE_VMALLOC.
Signed-off-by: Song Liu <song@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge misc fixes from Andrew Morton:
"13 patches.
Subsystems affected by this patch series: mm (memory-failure, memcg,
userfaultfd, hugetlbfs, mremap, oom-kill, kasan, hmm), and kcov"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove()
kcov: don't generate a warning on vm_insert_page()'s failure
MAINTAINERS: add Vincenzo Frascino to KASAN reviewers
oom_kill.c: futex: delay the OOM reaper to allow time for proper futex cleanup
selftest/vm: add skip support to mremap_test
selftest/vm: support xfail in mremap_test
selftest/vm: verify remap destination address in mremap_test
selftest/vm: verify mmap addr in mremap_test
mm, hugetlb: allow for "high" userspace addresses
userfaultfd: mark uffd_wp regardless of VM_WRITE flag
memcg: sync flush only if periodic flush is delayed
mm/memory-failure.c: skip huge_zero_page in memory_failure()
mm/hwpoison: fix race between hugetlb free/demotion and memory_failure_hugetlb()
Huge vmalloc higher-order backing pages were allocated with __GFP_COMP
in order to allow the sub-pages to be refcounted by callers such as
"remap_vmalloc_page [sic]" (remap_vmalloc_range).
However a similar problem exists for other struct page fields callers
use, for example fb_deferred_io_fault() takes a vmalloc'ed page and
not only refcounts it but uses ->lru, ->mapping, ->index.
This is not compatible with compound sub-pages, and can cause bad page
state issues like
BUG: Bad page state in process swapper/0 pfn:00743
page:(____ptrval____) refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x743
flags: 0x7ffff000000000(node=0|zone=0|lastcpupid=0x7ffff)
raw: 007ffff000000000 c00c00000001d0c8 c00c00000001d0c8 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: corrupted mapping in tail page
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.18.0-rc3-00082-gfc6fff4a7ce1-dirty #2810
Call Trace:
dump_stack_lvl+0x74/0xa8 (unreliable)
bad_page+0x12c/0x170
free_tail_pages_check+0xe8/0x190
free_pcp_prepare+0x31c/0x4e0
free_unref_page+0x40/0x1b0
__vunmap+0x1d8/0x420
...
The correct approach is to use split high-order pages for the huge
vmalloc backing. These allow callers to treat them in exactly the same
way as individually-allocated order-0 pages.
Link: https://lore.kernel.org/all/14444103-d51b-0fb3-ee63-c3f182f0b546@molgen.mpg.de/
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Menzel <pmenzel@molgen.mpg.de>
Cc: Song Liu <songliubraving@fb.com>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrey Konovalov