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After commit c0e473a0d226 ("block: fix race between set_blocksize and read
paths") was merged, set_blocksize() called by sb_set_blocksize() now locks
the inode of the backing device file. As a result of this change, syzbot
started reporting deadlock warnings due to a circular dependency involving
the semaphore "ns_sem" of the nilfs object, the inode lock of the backing
device file, and the locks that this inode lock is transitively dependent
on.
This is caused by a new lock dependency added by the above change, since
init_nilfs() calls sb_set_blocksize() in the lock section of "ns_sem".
However, these warnings are false positives because init_nilfs() is called
in the early stage of the mount operation and the filesystem has not yet
started.
The reason why "ns_sem" is locked in init_nilfs() was to avoid a race
condition in nilfs_fill_super() caused by sharing a nilfs object among
multiple filesystem instances (super block structures) in the early
implementation. However, nilfs objects and super block structures have
long ago become one-to-one, and there is no longer any need to use the
semaphore there.
So, fix this issue by removing the use of the semaphore "ns_sem" in
init_nilfs().
Link: https://lkml.kernel.org/r/20250503053327.12294-1-konishi.ryusuke@gmail.com
Fixes: c0e473a0d226 ("block: fix race between set_blocksize and read paths")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+00f7f5b884b117ee6773@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=00f7f5b884b117ee6773
Tested-by: syzbot+00f7f5b884b117ee6773@syzkaller.appspotmail.com
Reported-by: syzbot+f30591e72bfc24d4715b@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=f30591e72bfc24d4715b
Tested-by: syzbot+f30591e72bfc24d4715b@syzkaller.appspotmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since commit d2d786714080 ("mm/hugetlb: enable bootmem allocation from CMA
areas"), a flag is used to mark hugetlb folios as allocated from CMA.
This flag is also used to decide if it should be freed to CMA.
However, the flag isn't copied to the smaller folios when a hugetlb folio
is broken up for demotion, which would cause it to be freed incorrectly.
Fix this by copying the flag to the smaller order hugetlb pages created
from the original one.
Link: https://lkml.kernel.org/r/20250501044325.20365-1-fvdl@google.com
Fixes: d2d786714080 ("mm/hugetlb: enable bootmem allocation from CMA areas")
Signed-off-by: Frank van der Linden <fvdl@google.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Jane Chu <Jane.Chu@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The !CONFIG_THP_SWAP check existed before just fine because slot cache
would reject high order allocation and let the caller split all folios and
try again.
But slot cache is gone, so large allocation will directly go to the
allocator, and the allocator should just fail silently to inform caller to
do the folio split, this is totally fine and expected.
Remove this meaningless warning.
Link: https://lkml.kernel.org/r/20250429094803.85518-1-ryncsn@gmail.com
Fixes: 0ff67f990bd4 ("mm, swap: remove swap slot cache")
Signed-off-by: Kairui Song <kasong@tencent.com>
Reported-by: Heiko Carstens <hca@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/20250428135252.25453B17-hca@linux.ibm.com/
Tested-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The compiler is unaware of the size of code generated by the ".rept"
assembler directive. This results in the compiler emitting branch
instructions where the offset to branch to exceeds the maximum allowed
value, resulting in build failures like the following:
CC protection_keys
/tmp/ccypKWAE.s: Assembler messages:
/tmp/ccypKWAE.s:2073: Error: operand out of range (0x0000000000020158
is not between 0xffffffffffff8000 and 0x0000000000007ffc)
/tmp/ccypKWAE.s:2509: Error: operand out of range (0x0000000000020130
is not between 0xffffffffffff8000 and 0x0000000000007ffc)
Fix the issue by manually adding nop instructions using the preprocessor.
Link: https://lkml.kernel.org/r/20250428131937.641989-2-nysal@linux.ibm.com
Fixes: 46036188ea1f ("selftests/mm: build with -O2")
Reported-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Nysal Jan K.A. <nysal@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Reviewed-by: Donet Tom <donettom@linux.ibm.com>
Tested-by: Donet Tom <donettom@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Commit 50910acd6f615 ("selftests/mm: use sys_pkey helpers consistently")
added a pkey_util.c to refactor some of the protection_keys functions
accessible by other tests. But this broken the build in powerpc in two
ways,
pkey-powerpc.h: In function `arch_is_powervm':
pkey-powerpc.h:73:21: error: storage size of `buf' isn't known
73 | struct stat buf;
| ^~~
pkey-powerpc.h:75:14: error: implicit declaration of function `stat'; did you mean `strcat'? [-Wimplicit-function-declaration]
75 | if ((stat("/sys/firmware/devicetree/base/ibm,partition-name", &buf) == 0) &&
| ^~~~
| strcat
Since pkey_util.c includes pkeys-helper.h, which in turn includes pkeys-powerpc.h,
stat.h including is missing for "struct stat". This is fixed by adding "sys/stat.h"
in pkeys-powerpc.h
Secondly,
pkey-powerpc.h:55:18: warning: format `%llx' expects argument of type `long long unsigned int', but argument 3 has type `u64' {aka `long unsigned int'} [-Wformat=]
55 | dprintf4("%s() changing %016llx to %016llx\n",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
56 | __func__, __read_pkey_reg(), pkey_reg);
| ~~~~~~~~~~~~~~~~~
| |
| u64 {aka long unsigned int}
pkey-helpers.h:63:32: note: in definition of macro `dprintf_level'
63 | sigsafe_printf(args); \
| ^~~~
These format specifier related warning are removed by adding
"__SANE_USERSPACE_TYPES__" to pkeys_utils.c.
Link: https://lkml.kernel.org/r/20250428131937.641989-1-nysal@linux.ibm.com
Fixes: 50910acd6f61 ("selftests/mm: use sys_pkey helpers consistently")
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Nysal Jan K.A. <nysal@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Introduce struct vm_struct::requested_size so that the requested
(re)allocation size is retained separately from the allocated area size.
This means that KASAN will correctly poison the correct spans of requested
bytes. This also means we can support growing the usable portion of an
allocation that can already be supported by the existing area's existing
allocation.
Link: https://lkml.kernel.org/r/20250426001105.it.679-kees@kernel.org
Fixes: 3ddc2fefe6f3 ("mm: vmalloc: implement vrealloc()")
Signed-off-by: Kees Cook <kees@kernel.org>
Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Closes: https://lore.kernel.org/all/20250408192503.6149a816@outsider.home/
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The current implementation of the guard region tests assume that /tmp is
mounted as tmpfs, that is shmem.
This isn't always the case, and at least one instance of a spurious test
failure has been reported as a result.
This assumption is unsafe, rushed and silly - and easily remedied by
simply using memfd, so do so.
We also have to fixup the readonly_file test to explicitly only be
applicable to file-backed cases.
Link: https://lkml.kernel.org/r/20250425162436.564002-1-lorenzo.stoakes@oracle.com
Fixes: 272f37d3e99a ("tools/selftests: expand all guard region tests to file-backed")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reported-by: Ryan Roberts <ryan.roberts@arm.com>
Closes: https://lore.kernel.org/linux-mm/a2d2766b-0ab4-437b-951a-8595a7506fe9@arm.com/
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently quota recovery is synchronized with unmount using sb->s_umount
semaphore. That is however prone to deadlocks because
flush_workqueue(osb->ocfs2_wq) called from umount code can wait for quota
recovery to complete while ocfs2_finish_quota_recovery() waits for
sb->s_umount semaphore.
Grabbing of sb->s_umount semaphore in ocfs2_finish_quota_recovery() is
only needed to protect that function from disabling of quotas from
ocfs2_dismount_volume(). Handle this problem by disabling quota recovery
early during unmount in ocfs2_dismount_volume() instead so that we can
drop acquisition of sb->s_umount from ocfs2_finish_quota_recovery().
Link: https://lkml.kernel.org/r/20250424134515.18933-6-jack@suse.cz
Fixes: 5f530de63cfc ("ocfs2: Use s_umount for quota recovery protection")
Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Shichangkuo <shi.changkuo@h3c.com>
Reported-by: Murad Masimov <m.masimov@mt-integration.ru>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Tested-by: Heming Zhao <heming.zhao@suse.com>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We will need ocfs2 recovery thread to acknowledge transitions of
recovery_state when disabling particular types of recovery. This is
similar to what currently happens when disabling recovery completely, just
more general. Implement the handshake and use it for exit from recovery.
Link: https://lkml.kernel.org/r/20250424134515.18933-5-jack@suse.cz
Fixes: 5f530de63cfc ("ocfs2: Use s_umount for quota recovery protection")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Tested-by: Heming Zhao <heming.zhao@suse.com>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Murad Masimov <m.masimov@mt-integration.ru>
Cc: Shichangkuo <shi.changkuo@h3c.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "ocfs2: Fix deadlocks in quota recovery", v3.
This implements another approach to fixing quota recovery deadlocks. We
avoid grabbing sb->s_umount semaphore from ocfs2_finish_quota_recovery()
and instead stop quota recovery early in ocfs2_dismount_volume().
This patch (of 3):
We will need more recovery states than just pure enable / disable to fix
deadlocks with quota recovery. Switch osb->disable_recovery to enum.
Link: https://lkml.kernel.org/r/20250424134301.1392-1-jack@suse.cz
Link: https://lkml.kernel.org/r/20250424134515.18933-4-jack@suse.cz
Fixes: 5f530de63cfc ("ocfs2: Use s_umount for quota recovery protection")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Tested-by: Heming Zhao <heming.zhao@suse.com>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Murad Masimov <m.masimov@mt-integration.ru>
Cc: Shichangkuo <shi.changkuo@h3c.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When I started working for BayLibre I wasn't aware that the mailserver
rewrote the sender address and so a few commits entered kernel history
with a working but unexpected address. Map the unexpected to the intended
one. This also makes the author of those commits (e.g. 32b4f1a4f07f
("pwm: jz4740: Another few conversions to regmap_{set,clear}_bits()"))
match the address used in the sign-off line.
Link: https://lkml.kernel.org/r/20250424060250.3085683-2-u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
As part of the ongoing efforts to sub-divide memory management
maintainership and reviewership, establish a section for Transparent Huge
Page support and add appropriate maintainers and reviewers.
[lorenzo.stoakes@oracle.com: add Dev Jain as THP reviewer]
Link: https://lkml.kernel.org/r/327e6f2f-0f0f-48af-9ca2-3f8cadf0d8bf@lucifer.local
Link: https://lkml.kernel.org/r/20250424111632.103637-1-lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mariano Pache <npache@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
While discussing some userfaultfd relevant issues recently, Andrea noticed
a potential ABI breakage with -EAGAIN on almost all userfaultfd ioctl()s.
Quote from Andrea, explaining how -EAGAIN was processed, and how this
should fix it (taking example of UFFDIO_COPY ioctl):
The "mmap_changing" and "stale pmd" conditions are already reported as
-EAGAIN written in the copy field, this does not change it. This change
removes the subnormal case that left copy.copy uninitialized and required
apps to explicitly set the copy field to get deterministic
behavior (which is a requirement contrary to the documentation in both
the manpage and source code). In turn there's no alteration to backwards
compatibility as result of this change because userland will find the
copy field consistently set to -EAGAIN, and not anymore sometime -EAGAIN
and sometime uninitialized.
Even then the change only can make a difference to non cooperative users
of userfaultfd, so when UFFD_FEATURE_EVENT_* is enabled, which is not
true for the vast majority of apps using userfaultfd or this unintended
uninitialized field may have been noticed sooner.
Meanwhile, since this bug existed for years, it also almost affects all
ioctl()s that was introduced later. Besides UFFDIO_ZEROPAGE, these also
get affected in the same way:
- UFFDIO_CONTINUE
- UFFDIO_POISON
- UFFDIO_MOVE
This patch should have fixed all of them.
Link: https://lkml.kernel.org/r/20250424215729.194656-2-peterx@redhat.com
Fixes: df2cc96e7701 ("userfaultfd: prevent non-cooperative events vs mcopy_atomic races")
Fixes: f619147104c8 ("userfaultfd: add UFFDIO_CONTINUE ioctl")
Fixes: fc71884a5f59 ("mm: userfaultfd: add new UFFDIO_POISON ioctl")
Fixes: adef440691ba ("userfaultfd: UFFDIO_MOVE uABI")
Signed-off-by: Peter Xu <peterx@redhat.com>
Reported-by: Andrea Arcangeli <aarcange@redhat.com>
Suggested-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When running mm selftest to verify mm patches, 'compaction_test' case
failed on an x86 server with 1TB memory. And the root cause is that it
has too much free memory than what the test supports.
The test case tries to allocate 100000 huge pages, which is about 200 GB
for that x86 server, and when it succeeds, it expects it's large than 1/3
of 80% of the free memory in system. This logic only works for platform
with 750 GB ( 200 / (1/3) / 80% ) or less free memory, and may raise false
alarm for others.
Fix it by changing the fixed page number to self-adjustable number
according to the real number of free memory.
Link: https://lkml.kernel.org/r/20250423103645.2758-1-feng.tang@linux.alibaba.com
Fixes: bd67d5c15cc1 ("Test compaction of mlocked memory")
Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com>
Acked-by: Dev Jain <dev.jain@arm.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Tested-by: Baolin Wang <baolin.wang@inux.alibaba.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Sri Jayaramappa <sjayaram@akamai.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In furtherance of ongoing efforts to ensure people are aware of who
de-facto maintains/has an interest in specific parts of mm, as well trying
to avoid get_maintainers.pl listing only Andrew and the mailing list for
mm files - establish a 'core' memory management section establishing David
as co-maintainer alongside Andrew (thanks David for volunteering!) along
with a number of relevant reviewers.
We try to keep things as fine-grained as possible, so we place only
obviously 'general' mm things here. For files which are specific to a
particular part of mm, we prefer new entries.
Link: https://lkml.kernel.org/r/20250423123042.59082-1-lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
commit 7e119cff9d0a ("ocfs2: convert w_pages to w_folios") and commit
9a5e08652dc4b ("ocfs2: use an array of folios instead of an array of
pages") save -ENOMEM in the folio array upon allocation failure and call
the folio array free code.
The folio array free code expects either valid folio pointers or NULL.
Finding the -ENOMEM will result in a panic. Fix by NULLing the error
folio entry.
Link: https://lkml.kernel.org/r/c879a52b-835c-4fa0-902b-8b2e9196dcbd@oracle.com
Fixes: 7e119cff9d0a ("ocfs2: convert w_pages to w_folios")
Fixes: 9a5e08652dc4b ("ocfs2: use an array of folios instead of an array of pages")
Signed-off-by: Mark Tinguely <mark.tinguely@oracle.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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