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1154429 commits

Author SHA1 Message Date
Alistair Popple
7d4a8be0c4 mm/mmu_notifier: remove unused mmu_notifier_range_update_to_read_only export
mmu_notifier_range_update_to_read_only() was originally introduced in
commit c6d23413f8 ("mm/mmu_notifier:
mmu_notifier_range_update_to_read_only() helper") as an optimisation for
device drivers that know a range has only been mapped read-only.  However
there are no users of this feature so remove it.  As it is the only user
of the struct mmu_notifier_range.vma field remove that also.

Link: https://lkml.kernel.org/r/20230110025722.600912-1-apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:54 -08:00
Baolin Wang
9e5522715e mm: compaction: avoid fragmentation score calculation for empty zones
There is no need to calculate the fragmentation score for empty zones.

Link: https://lkml.kernel.org/r/100331ad9d274a9725e687b00d85d75d7e4a17c7.1673342761.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:54 -08:00
Baolin Wang
8fff8b6f8d mm: compaction: add missing kcompactd wakeup trace event
Add missing kcompactd wakeup trace event for proactive compaction,
meanwhile use order = -1 and the highest zone index of the pgdat for the
kcompactd wakeup trace event by proactive compaction.

Link: https://lkml.kernel.org/r/cbf8097a2d8a1b6800991f2a21575550d3613ce6.1673342761.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:54 -08:00
Baolin Wang
1bfb7684db mm: compaction: count the migration scanned pages events for proactive compaction
The proactive compaction will reuse per-node kcompactd threads, so we
should also count the KCOMPACTD_MIGRATE_SCANNED and KCOMPACTD_FREE_SCANNED
events for proactive compaction.

Link: https://lkml.kernel.org/r/b7f1ece1adc17defa47e3667b5f9fd61f496517a.1673342761.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:53 -08:00
Baolin Wang
753ec50d97 mm: compaction: move list validation into compact_zone()
Move the cc.freepages and cc.migratepages list validation into compact_zone()
to remove some duplicate code.

Link: https://lkml.kernel.org/r/15cf54f7d762e87b04ac3cc74536f7d1ebbcd8cd.1673342761.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:53 -08:00
Baolin Wang
c6835e8d86 mm: compaction: remove redundant VM_BUG_ON() in compact_zone()
Patch series "Some small improvements for compaction".

When I did some compaction testing, I found some small room for
improvement as well as some code cleanups.


This patch (of 5):

The compaction_suitable() will never return values other than
COMPACT_SUCCESS, COMPACT_SKIPPED and COMPACT_CONTINUE, so after validation
of COMPACT_SUCCESS and COMPACT_SKIPPED, we will never hit other unexpected
case.  Thus remove the redundant VM_BUG_ON() validation for the return
values of compaction_suitable().

Link: https://lkml.kernel.org/r/cover.1673342761.git.baolin.wang@linux.alibaba.com
Link: https://lkml.kernel.org/r/740a2396d9b98154dba76e326cba5e798b640ead.1673342761.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:53 -08:00
Vernon Yang
baabcfc93d mm/mmap: fix typo in comment
Replace "parital" with "partial".

Link: https://lkml.kernel.org/r/20230110145353.1658435-1-vernon2gm@gmail.com
Signed-off-by: Vernon Yang <vernon2gm@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:53 -08:00
Vernon Yang
c5d5546ea0 maple_tree: remove the parameter entry of mas_preallocate
The parameter entry of mas_preallocate is not used, so drop it.

Link: https://lkml.kernel.org/r/20230110154211.1758562-1-vernon2gm@gmail.com
Signed-off-by: Vernon Yang <vernon2gm@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:52 -08:00
SeongJae Park
75cb348714 selftests/damon/debugfs_rm_non_contexts: hide expected write error messages
A selftest case for DAMON debugfs interface has a test for expected
failure.  To make the test output clean, hide the expected failure error
message.

Link: https://lkml.kernel.org/r/20230110190400.119388-9-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:52 -08:00
SeongJae Park
16ddcb1549 selftests/damon/sysfs: hide expected write failures
DAMON selftests for sysfs (sysfs.sh) tests if some writes to DAMON sysfs
interface files fails as expected.  It makes the test results noisy with
the failure error message because it tests a number of such failures. 
Redirect the expected failure error messages to /dev/null to make the
results clean.

Link: https://lkml.kernel.org/r/20230110190400.119388-8-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:52 -08:00
SeongJae Park
2d2230efbc MAINTAINERS/DAMON: link maintainer profile, git trees, and website
Add links to below DAMON development related resource to DAMON section in
MAINTAINERS file.

- The basic policies and expectations of DAMON development,
- DAMON development trees, and
- DAMON introduction website.

Link: https://lkml.kernel.org/r/20230110190400.119388-7-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:52 -08:00
SeongJae Park
e7366f3a2e Docs/mm/damon: add a maintainer-profile for DAMON
Document the basic policies and expectations for DAMON development.

Link: https://lkml.kernel.org/r/20230110190400.119388-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:52 -08:00
SeongJae Park
9a47c411cc Docs/admin-guide/mm/damon/usage: update DAMOS actions/filters supports of each DAMON operations set
Supports of each DAMOS action and filters are up to DAMON operations set
implementation, but it's not mentioned in detail on the documentation. 
Update the information on the usage document.

Link: https://lkml.kernel.org/r/20230110190400.119388-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:51 -08:00
SeongJae Park
86834644e3 Docs/mm/damon/index: mention DAMOS on the intro
What DAMON aims to do is not only access monitoring but efficient and
effective access-aware system operations.  And DAMon-based Operation
Schemes (DAMOS) is the important feature of DAMON for the goal.  Make the
intro of DAMON documentation to emphasize the goal and mention DAMOS.

Link: https://lkml.kernel.org/r/20230110190400.119388-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:51 -08:00
SeongJae Park
55901e89d2 mm/damon/core: update kernel-doc comments for DAMOS filters supports of each DAMON operations set
Supports of each DAMOS filter type are up to DAMON operations set
implementation in use, but not well mentioned on the kernel-doc comments. 
Add the comment.

Link: https://lkml.kernel.org/r/20230110190400.119388-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:51 -08:00
SeongJae Park
fb6f026b83 mm/damon/core: update kernel-doc comments for DAMOS action supports of each DAMON operations set
Patch series "mm/damon: trivial fixups".

This patchset contains patches for trivial fixups of DAMON's
documentation, MAINTAINERS section, and selftests.


This patch (of 8):

Supports of each DAMOS action are up to DAMON operations set
implementation in use, but not well mentioned on the kernel-doc comments. 
Add the comment.

Link: https://lkml.kernel.org/r/20230110190400.119388-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20230110190400.119388-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:51 -08:00
Fabio M. De Francesco
92b64bd01f mm/highmem: add notes about conversions from kmap{,_atomic}()
kmap() and kmap_atomic() have been deprecated.  kmap_local_page() should
always be used in new code and the call sites of the two deprecated
functions should be converted.  This latter task can lead to errors if it
is not carried out with the necessary attention to the context around and
between the maps and unmaps.

Therefore, add further information to the Highmem's documentation for the
purpose to make it clearer that (1) kmap() and kmap_atomic() must not any
longer be called in new code and (2) developers doing conversions from
kmap() amd kmap_atomic() are expected to take care of the context around
and between the maps and unmaps, in order to not break the code.

Relevant parts of this patch have been taken from messages exchanged
privately with Ira Weiny (thanks!).

[fmdefrancesco@gmail.com: merge two sentences into one, per Bagas]
  Link: https://lkml.kernel.org/r/20230119123945.10471-1-fmdefrancesco@gmail.com
Link: https://lkml.kernel.org/r/20221207225308.8290-1-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:32:50 -08:00
Andrew Morton
5ab0fc155d Sync mm-stable with mm-hotfixes-stable to pick up dependent patches
Merge branch 'mm-hotfixes-stable' into mm-stable
2023-01-31 17:25:17 -08:00
Kefeng Wang
ac86f547ca mm: memcg: fix NULL pointer in mem_cgroup_track_foreign_dirty_slowpath()
As commit 18365225f0 ("hwpoison, memcg: forcibly uncharge LRU pages"),
hwpoison will forcibly uncharg a LRU hwpoisoned page, the folio_memcg
could be NULl, then, mem_cgroup_track_foreign_dirty_slowpath() could
occurs a NULL pointer dereference, let's do not record the foreign
writebacks for folio memcg is null in mem_cgroup_track_foreign_dirty() to
fix it.

Link: https://lkml.kernel.org/r/20230129040945.180629-1-wangkefeng.wang@huawei.com
Fixes: 97b27821b4 ("writeback, memcg: Implement foreign dirty flushing")
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reported-by: Ma Wupeng <mawupeng1@huawei.com>
Tested-by: Miko Larsson <mikoxyzzz@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Ma Wupeng <mawupeng1@huawei.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:10 -08:00
ye xingchen
1e90e35b62 Kconfig.debug: fix the help description in SCHED_DEBUG
The correct file path for SCHED_DEBUG is /sys/kernel/debug/sched.

Link: https://lkml.kernel.org/r/202301291013573466558@zte.com.cn
Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:10 -08:00
Longlong Xia
7717fc1a12 mm/swapfile: add cond_resched() in get_swap_pages()
The softlockup still occurs in get_swap_pages() under memory pressure.  64
CPU cores, 64GB memory, and 28 zram devices, the disksize of each zram
device is 50MB with same priority as si.  Use the stress-ng tool to
increase memory pressure, causing the system to oom frequently.

The plist_for_each_entry_safe() loops in get_swap_pages() could reach tens
of thousands of times to find available space (extreme case:
cond_resched() is not called in scan_swap_map_slots()).  Let's add
cond_resched() into get_swap_pages() when failed to find available space
to avoid softlockup.

Link: https://lkml.kernel.org/r/20230128094757.1060525-1-xialonglong1@huawei.com
Signed-off-by: Longlong Xia <xialonglong1@huawei.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Chen Wandun <chenwandun@huawei.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:10 -08:00
Zhaoyang Huang
993f57e027 mm: use stack_depot_early_init for kmemleak
Mirsad report the below error which is caused by stack_depot_init()
failure in kvcalloc.  Solve this by having stackdepot use
stack_depot_early_init().

On 1/4/23 17:08, Mirsad Goran Todorovac wrote:
I hate to bring bad news again, but there seems to be a problem with the output of /sys/kernel/debug/kmemleak:

[root@pc-mtodorov ~]# cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff951c118568b0 (size 16):
comm "kworker/u12:2", pid 56, jiffies 4294893952 (age 4356.548s)
hex dump (first 16 bytes):
    6d 65 6d 73 74 69 63 6b 30 00 00 00 00 00 00 00 memstick0.......
    backtrace:
[root@pc-mtodorov ~]#

Apparently, backtrace of called functions on the stack is no longer
printed with the list of memory leaks.  This appeared on Lenovo desktop
10TX000VCR, with AlmaLinux 8.7 and BIOS version M22KT49A (11/10/2022) and
6.2-rc1 and 6.2-rc2 builds.  This worked on 6.1 with the same
CONFIG_KMEMLEAK=y and MGLRU enabled on a vanilla mainstream kernel from
Mr.  Torvalds' tree.  I don't know if this is deliberate feature for some
reason or a bug.  Please find attached the config, lshw and kmemleak
output.

[vbabka@suse.cz: remove stack_depot_init() call]
Link: https://lore.kernel.org/all/5272a819-ef74-65ff-be61-4d2d567337de@alu.unizg.hr/
Link: https://lkml.kernel.org/r/1674091345-14799-2-git-send-email-zhaoyang.huang@unisoc.com
Fixes: 56a61617dd ("mm: use stack_depot for recording kmemleak's backtrace")
Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: ke.wang <ke.wang@unisoc.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:10 -08:00
Phillip Lougher
f65c4bbbd6 Squashfs: fix handling and sanity checking of xattr_ids count
A Sysbot [1] corrupted filesystem exposes two flaws in the handling and
sanity checking of the xattr_ids count in the filesystem.  Both of these
flaws cause computation overflow due to incorrect typing.

In the corrupted filesystem the xattr_ids value is 4294967071, which
stored in a signed variable becomes the negative number -225.

Flaw 1 (64-bit systems only):

The signed integer xattr_ids variable causes sign extension.

This causes variable overflow in the SQUASHFS_XATTR_*(A) macros.  The
variable is first multiplied by sizeof(struct squashfs_xattr_id) where the
type of the sizeof operator is "unsigned long".

On a 64-bit system this is 64-bits in size, and causes the negative number
to be sign extended and widened to 64-bits and then become unsigned.  This
produces the very large number 18446744073709548016 or 2^64 - 3600.  This
number when rounded up by SQUASHFS_METADATA_SIZE - 1 (8191 bytes) and
divided by SQUASHFS_METADATA_SIZE overflows and produces a length of 0
(stored in len).

Flaw 2 (32-bit systems only):

On a 32-bit system the integer variable is not widened by the unsigned
long type of the sizeof operator (32-bits), and the signedness of the
variable has no effect due it always being treated as unsigned.

The above corrupted xattr_ids value of 4294967071, when multiplied
overflows and produces the number 4294963696 or 2^32 - 3400.  This number
when rounded up by SQUASHFS_METADATA_SIZE - 1 (8191 bytes) and divided by
SQUASHFS_METADATA_SIZE overflows again and produces a length of 0.

The effect of the 0 length computation:

In conjunction with the corrupted xattr_ids field, the filesystem also has
a corrupted xattr_table_start value, where it matches the end of
filesystem value of 850.

This causes the following sanity check code to fail because the
incorrectly computed len of 0 matches the incorrect size of the table
reported by the superblock (0 bytes).

    len = SQUASHFS_XATTR_BLOCK_BYTES(*xattr_ids);
    indexes = SQUASHFS_XATTR_BLOCKS(*xattr_ids);

    /*
     * The computed size of the index table (len bytes) should exactly
     * match the table start and end points
    */
    start = table_start + sizeof(*id_table);
    end = msblk->bytes_used;

    if (len != (end - start))
            return ERR_PTR(-EINVAL);

Changing the xattr_ids variable to be "usigned int" fixes the flaw on a
64-bit system.  This relies on the fact the computation is widened by the
unsigned long type of the sizeof operator.

Casting the variable to u64 in the above macro fixes this flaw on a 32-bit
system.

It also means 64-bit systems do not implicitly rely on the type of the
sizeof operator to widen the computation.

[1] https://lore.kernel.org/lkml/000000000000cd44f005f1a0f17f@google.com/

Link: https://lkml.kernel.org/r/20230127061842.10965-1-phillip@squashfs.org.uk
Fixes: 506220d2ba ("squashfs: add more sanity checks in xattr id lookup")
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reported-by: <syzbot+082fa4af80a5bb1a9843@syzkaller.appspotmail.com>
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Fedor Pchelkin <pchelkin@ispras.ru>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:10 -08:00
Tom Saeger
c1c551bebf sh: define RUNTIME_DISCARD_EXIT
sh vmlinux fails to link with GNU ld < 2.40 (likely < 2.36) since
commit 99cb0d917f ("arch: fix broken BuildID for arm64 and riscv").

This is similar to fixes for powerpc and s390:
commit 4b9880dbf3 ("powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXIT").
commit a494398bde ("s390: define RUNTIME_DISCARD_EXIT to fix link error
with GNU ld < 2.36").

  $ sh4-linux-gnu-ld --version | head -n1
  GNU ld (GNU Binutils for Debian) 2.35.2

  $ make ARCH=sh CROSS_COMPILE=sh4-linux-gnu- microdev_defconfig
  $ make ARCH=sh CROSS_COMPILE=sh4-linux-gnu-

  `.exit.text' referenced in section `__bug_table' of crypto/algboss.o:
  defined in discarded section `.exit.text' of crypto/algboss.o
  `.exit.text' referenced in section `__bug_table' of
  drivers/char/hw_random/core.o: defined in discarded section
  `.exit.text' of drivers/char/hw_random/core.o
  make[2]: *** [scripts/Makefile.vmlinux:34: vmlinux] Error 1
  make[1]: *** [Makefile:1252: vmlinux] Error 2

arch/sh/kernel/vmlinux.lds.S keeps EXIT_TEXT:

	/*
	 * .exit.text is discarded at runtime, not link time, to deal with
	 * references from __bug_table
	 */
	.exit.text : AT(ADDR(.exit.text)) { EXIT_TEXT }

However, EXIT_TEXT is thrown away by
DISCARD(include/asm-generic/vmlinux.lds.h) because
sh does not define RUNTIME_DISCARD_EXIT.

GNU ld 2.40 does not have this issue and builds fine.
This corresponds with Masahiro's comments in a494398bde:
"Nathan [Chancellor] also found that binutils
commit 21401fc7bf67 ("Duplicate output sections in scripts") cured this
issue, so we cannot reproduce it with binutils 2.36+, but it is better
to not rely on it."

Link: https://lkml.kernel.org/r/9166a8abdc0f979e50377e61780a4bba1dfa2f52.1674518464.git.tom.saeger@oracle.com
Fixes: 99cb0d917f ("arch: fix broken BuildID for arm64 and riscv")
Link: https://lore.kernel.org/all/Y7Jal56f6UBh1abE@dev-arch.thelio-3990X/
Link: https://lore.kernel.org/all/20230123194218.47ssfzhrpnv3xfez@oracle.com/
Signed-off-by: Tom Saeger <tom.saeger@oracle.com>
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dennis Gilmore <dennis@ausil.us>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:09 -08:00
Matthew Wilcox (Oracle)
88d7b12068 highmem: round down the address passed to kunmap_flush_on_unmap()
We already round down the address in kunmap_local_indexed() which is the
other implementation of __kunmap_local().  The only implementation of
kunmap_flush_on_unmap() is PA-RISC which is expecting a page-aligned
address.  This may be causing PA-RISC to be flushing the wrong addresses
currently.

Link: https://lkml.kernel.org/r/20230126200727.1680362-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Fixes: 298fa1ad55 ("highmem: Provide generic variant of kmap_atomic*")
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Helge Deller <deller@gmx.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:09 -08:00
Mike Kravetz
73bdf65ea7 migrate: hugetlb: check for hugetlb shared PMD in node migration
migrate_pages/mempolicy semantics state that CAP_SYS_NICE is required to
move pages shared with another process to a different node.  page_mapcount
> 1 is being used to determine if a hugetlb page is shared.  However, a
hugetlb page will have a mapcount of 1 if mapped by multiple processes via
a shared PMD.  As a result, hugetlb pages shared by multiple processes and
mapped with a shared PMD can be moved by a process without CAP_SYS_NICE.

To fix, check for a shared PMD if mapcount is 1.  If a shared PMD is found
consider the page shared.

Link: https://lkml.kernel.org/r/20230126222721.222195-3-mike.kravetz@oracle.com
Fixes: e2d8cf4055 ("migrate: add hugepage migration code to migrate_pages()")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Peter Xu <peterx@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: James Houghton <jthoughton@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:09 -08:00
Mike Kravetz
3489dbb696 mm: hugetlb: proc: check for hugetlb shared PMD in /proc/PID/smaps
Patch series "Fixes for hugetlb mapcount at most 1 for shared PMDs".

This issue of mapcount in hugetlb pages referenced by shared PMDs was
discussed in [1].  The following two patches address user visible behavior
caused by this issue.

[1] https://lore.kernel.org/linux-mm/Y9BF+OCdWnCSilEu@monkey/


This patch (of 2):

A hugetlb page will have a mapcount of 1 if mapped by multiple processes
via a shared PMD.  This is because only the first process increases the
map count, and subsequent processes just add the shared PMD page to their
page table.

page_mapcount is being used to decide if a hugetlb page is shared or
private in /proc/PID/smaps.  Pages referenced via a shared PMD were
incorrectly being counted as private.

To fix, check for a shared PMD if mapcount is 1.  If a shared PMD is found
count the hugetlb page as shared.  A new helper to check for a shared PMD
is added.

[akpm@linux-foundation.org: simplification, per David]
[akpm@linux-foundation.org: hugetlb.h: include page_ref.h for page_count()]
Link: https://lkml.kernel.org/r/20230126222721.222195-2-mike.kravetz@oracle.com
Fixes: 25ee01a2fc ("mm: hugetlb: proc: add hugetlb-related fields to /proc/PID/smaps")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Peter Xu <peterx@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: James Houghton <jthoughton@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:09 -08:00
Zach O'Keefe
edb5d0cf55 mm/MADV_COLLAPSE: catch !none !huge !bad pmd lookups
In commit 34488399fa ("mm/madvise: add file and shmem support to
MADV_COLLAPSE") we make the following change to find_pmd_or_thp_or_none():

	-       if (!pmd_present(pmde))
	-               return SCAN_PMD_NULL;
	+       if (pmd_none(pmde))
	+               return SCAN_PMD_NONE;

This was for-use by MADV_COLLAPSE file/shmem codepaths, where
MADV_COLLAPSE might identify a pte-mapped hugepage, only to have
khugepaged race-in, free the pte table, and clear the pmd.  Such codepaths
include:

A) If we find a suitably-aligned compound page of order HPAGE_PMD_ORDER
   already in the pagecache.
B) In retract_page_tables(), if we fail to grab mmap_lock for the target
   mm/address.

In these cases, collapse_pte_mapped_thp() really does expect a none (not
just !present) pmd, and we want to suitably identify that case separate
from the case where no pmd is found, or it's a bad-pmd (of course, many
things could happen once we drop mmap_lock, and the pmd could plausibly
undergo multiple transitions due to intervening fault, split, etc). 
Regardless, the code is prepared install a huge-pmd only when the existing
pmd entry is either a genuine pte-table-mapping-pmd, or the none-pmd.

However, the commit introduces a logical hole; namely, that we've allowed
!none- && !huge- && !bad-pmds to be classified as genuine
pte-table-mapping-pmds.  One such example that could leak through are swap
entries.  The pmd values aren't checked again before use in
pte_offset_map_lock(), which is expecting nothing less than a genuine
pte-table-mapping-pmd.

We want to put back the !pmd_present() check (below the pmd_none() check),
but need to be careful to deal with subtleties in pmd transitions and
treatments by various arch.

The issue is that __split_huge_pmd_locked() temporarily clears the present
bit (or otherwise marks the entry as invalid), but pmd_present() and
pmd_trans_huge() still need to return true while the pmd is in this
transitory state.  For example, x86's pmd_present() also checks the
_PAGE_PSE , riscv's version also checks the _PAGE_LEAF bit, and arm64 also
checks a PMD_PRESENT_INVALID bit.

Covering all 4 cases for x86 (all checks done on the same pmd value):

1) pmd_present() && pmd_trans_huge()
   All we actually know here is that the PSE bit is set. Either:
   a) We aren't racing with __split_huge_page(), and PRESENT or PROTNONE
      is set.
      => huge-pmd
   b) We are currently racing with __split_huge_page().  The danger here
      is that we proceed as-if we have a huge-pmd, but really we are
      looking at a pte-mapping-pmd.  So, what is the risk of this
      danger?

      The only relevant path is:

	madvise_collapse() -> collapse_pte_mapped_thp()

      Where we might just incorrectly report back "success", when really
      the memory isn't pmd-backed.  This is fine, since split could
      happen immediately after (actually) successful madvise_collapse().
      So, it should be safe to just assume huge-pmd here.

2) pmd_present() && !pmd_trans_huge()
   Either:
   a) PSE not set and either PRESENT or PROTNONE is.
      => pte-table-mapping pmd (or PROT_NONE)
   b) devmap.  This routine can be called immediately after
      unlocking/locking mmap_lock -- or called with no locks held (see
      khugepaged_scan_mm_slot()), so previous VMA checks have since been
      invalidated.

3) !pmd_present() && pmd_trans_huge()
  Not possible.

4) !pmd_present() && !pmd_trans_huge()
  Neither PRESENT nor PROTNONE set
  => not present

I've checked all archs that implement pmd_trans_huge() (arm64, riscv,
powerpc, longarch, x86, mips, s390) and this logic roughly translates
(though devmap treatment is unique to x86 and powerpc, and (3) doesn't
necessarily hold in general -- but that doesn't matter since
!pmd_present() always takes failure path).

Also, add a comment above find_pmd_or_thp_or_none() to help future
travelers reason about the validity of the code; namely, the possible
mutations that might happen out from under us, depending on how mmap_lock
is held (if at all).

Link: https://lkml.kernel.org/r/20230125225358.2576151-1-zokeefe@google.com
Fixes: 34488399fa ("mm/madvise: add file and shmem support to MADV_COLLAPSE")
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Reported-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:09 -08:00
Isaac J. Manjarres
8ef852f1cb Revert "mm: kmemleak: alloc gray object for reserved region with direct map"
This reverts commit 972fa3a7c1.

Kmemleak operates by periodically scanning memory regions for pointers to
allocated memory blocks to determine if they are leaked or not.  However,
reserved memory regions can be used for DMA transactions between a device
and a CPU, and thus, wouldn't contain pointers to allocated memory blocks,
making them inappropriate for kmemleak to scan.  Thus, revert this commit.

Link: https://lkml.kernel.org/r/20230124230254.295589-1-isaacmanjarres@google.com
Fixes: 972fa3a7c1 ("mm: kmemleak: alloc gray object for reserved region with direct map")
Signed-off-by: Isaac J. Manjarres <isaacmanjarres@google.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Calvin Zhang <calvinzhang.cool@gmail.com>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: <stable@vger.kernel.org>	[5.17+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:09 -08:00
Randy Dunlap
0d7866eace freevxfs: Kconfig: fix spelling
Fix a spello in freevxfs Kconfig.
(reported by codespell)

Link: https://lkml.kernel.org/r/20230124181638.15604-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:08 -08:00
Wei Yang
ab6ef70a8b maple_tree: should get pivots boundary by type
We should get pivots boundary by type.  Fixes a potential overindexing of
mt_pivots[].

Link: https://lkml.kernel.org/r/20221112234308.23823-1-richard.weiyang@gmail.com
Fixes: 54a611b605 ("Maple Tree: add new data structure")
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:08 -08:00
Eugen Hristev
889a904fe3 .mailmap: update e-mail address for Eugen Hristev
Update e-mail address.

Link: https://lkml.kernel.org/r/20230119072229.99603-1-eugen.hristev@collabora.com
Signed-off-by: Eugen Hristev <eugen.hristev@collabora.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:08 -08:00
Vlastimil Babka
d014cd7c1c mm, mremap: fix mremap() expanding for vma's with vm_ops->close()
Fabian has reported another regression in 6.1 due to ca3d76b0aa ("mm:
add merging after mremap resize").  The problem is that vma_merge() can
fail when vma has a vm_ops->close() method, causing is_mergeable_vma()
test to be negative.  This was happening for vma mapping a file from
fuse-overlayfs, which does have the method.  But when we are simply
expanding the vma, we never remove it due to the "merge" with the added
area, so the test should not prevent the expansion.

As a quick fix, check for such vmas and expand them using vma_adjust()
directly as was done before commit ca3d76b0aa.  For a more robust long
term solution we should try to limit the check for vma_ops->close only to
cases that actually result in vma removal, so that no merge would be
prevented unnecessarily.

[akpm@linux-foundation.org: fix indenting whitespace, reflow comment]
Link: https://lkml.kernel.org/r/20230117101939.9753-1-vbabka@suse.cz
Fixes: ca3d76b0aa ("mm: add merging after mremap resize")
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Fabian Vogt <fvogt@suse.com>
  Link: https://bugzilla.suse.com/show_bug.cgi?id=1206359#c35
Tested-by: Fabian Vogt <fvogt@suse.com>
Cc: Jakub Matěna <matenajakub@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:08 -08:00
Fedor Pchelkin
72e544b1b2 squashfs: harden sanity check in squashfs_read_xattr_id_table
While mounting a corrupted filesystem, a signed integer '*xattr_ids' can
become less than zero.  This leads to the incorrect computation of 'len'
and 'indexes' values which can cause null-ptr-deref in copy_bio_to_actor()
or out-of-bounds accesses in the next sanity checks inside
squashfs_read_xattr_id_table().

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Link: https://lkml.kernel.org/r/20230117105226.329303-2-pchelkin@ispras.ru
Fixes: 506220d2ba ("squashfs: add more sanity checks in xattr id lookup")
Reported-by: <syzbot+082fa4af80a5bb1a9843@syzkaller.appspotmail.com>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:08 -08:00
James Morse
6f28a26134 ia64: fix build error due to switch case label appearing next to declaration
Since commit aa06a9bd85 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to
report ITC frequency"), gcc 10.1.0 fails to build ia64 with the gnomic:
| ../arch/ia64/kernel/sys_ia64.c: In function 'ia64_clock_getres':
| ../arch/ia64/kernel/sys_ia64.c:189:3: error: a label can only be part of a statement and a declaration is not a statement
|   189 |   s64 tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);

This line appears immediately after a case label in a switch.

Move the declarations out of the case, to the top of the function.

Link: https://lkml.kernel.org/r/20230117151632.393836-1-james.morse@arm.com
Fixes: aa06a9bd85 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to report ITC frequency")
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Sergei Trofimovich <slyich@gmail.com>
Cc: Émeric Maschino <emeric.maschino@gmail.com>
Cc: matoro <matoro_mailinglist_kernel@matoro.tk>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:08 -08:00
Yu Zhao
de08eaa615 mm: multi-gen LRU: fix crash during cgroup migration
lru_gen_migrate_mm() assumes lru_gen_add_mm() runs prior to itself.  This
isn't true for the following scenario:

    CPU 1                         CPU 2

  clone()
    cgroup_can_fork()
                                cgroup_procs_write()
    cgroup_post_fork()
                                  task_lock()
                                  lru_gen_migrate_mm()
                                  task_unlock()
    task_lock()
    lru_gen_add_mm()
    task_unlock()

And when the above happens, kernel crashes because of linked list
corruption (mm_struct->lru_gen.list).

Link: https://lore.kernel.org/r/20230115134651.30028-1-msizanoen@qtmlabs.xyz/
Link: https://lkml.kernel.org/r/20230116034405.2960276-1-yuzhao@google.com
Fixes: bd74fdaea1 ("mm: multi-gen LRU: support page table walks")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Reported-by: msizanoen <msizanoen@qtmlabs.xyz>
Tested-by: msizanoen <msizanoen@qtmlabs.xyz>
Cc: <stable@vger.kernel.org>	[6.1+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:08 -08:00
Michal Hocko
55ab834a86 Revert "mm: add nodes= arg to memory.reclaim"
This reverts commit 12a5d39552.

Although it is recognized that a finer grained pro-active reclaim is
something we need and want the semantic of this implementation is really
ambiguous.

In a follow up discussion it became clear that there are two essential
usecases here.  One is to use memory.reclaim to pro-actively reclaim
memory and expectation is that the requested and reported amount of memory
is uncharged from the memcg.  Another usecase focuses on pro-active
demotion when the memory is merely shuffled around to demotion targets
while the overall charged memory stays unchanged.

The current implementation considers demoted pages as reclaimed and that
break both usecases.  [1] has tried to address the reporting part but
there are more issues with that summarized in [2] and follow up emails.

Let's revert the nodemask based extension of the memcg pro-active
reclaim for now until we settle with a more robust semantic.

[1] http://lkml.kernel.org/r/http://lkml.kernel.org/r/20221206023406.3182800-1-almasrymina@google.com
[2] http://lkml.kernel.org/r/Y5bsmpCyeryu3Zz1@dhcp22.suse.cz

Link: https://lkml.kernel.org/r/Y5xASNe1x8cusiTx@dhcp22.suse.cz
Fixes: 12a5d39552 ("mm: add nodes= arg to memory.reclaim")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Wei Xu <weixugc@google.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: zefan li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:07 -08:00
Nhat Pham
85b325815b zsmalloc: fix a race with deferred_handles storing
Currently, there is a race between zs_free() and zs_reclaim_page():
zs_reclaim_page() finds a handle to an allocated object, but before the
eviction happens, an independent zs_free() call to the same handle could
come in and overwrite the object value stored at the handle with the last
deferred handle.  When zs_reclaim_page() finally gets to call the eviction
handler, it will see an invalid object value (i.e the previous deferred
handle instead of the original object value).

This race happens quite infrequently.  We only managed to produce it with
out-of-tree developmental code that triggers zsmalloc writeback with a
much higher frequency than usual.

This patch fixes this race by storing the deferred handle in the object
header instead.  We differentiate the deferred handle from the other two
cases (handle for allocated object, and linkage for free object) with a
new tag.  If zspage reclamation succeeds, we will free these deferred
handles by walking through the zspage objects.  On the other hand, if
zspage reclamation fails, we reconstruct the zspage freelist (with the
deferred handle tag and allocated tag) before trying again with the
reclamation.

[arnd@arndb.de: avoid unused-function warning]
  Link: https://lkml.kernel.org/r/20230117170507.2651972-1-arnd@kernel.org
Link: https://lkml.kernel.org/r/20230110231701.326724-1-nphamcs@gmail.com
Fixes: 9997bc0175 ("zsmalloc: implement writeback mechanism for zsmalloc")
Signed-off-by: Nhat Pham <nphamcs@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:07 -08:00
Jann Horn
023f47a825 mm/khugepaged: fix ->anon_vma race
If an ->anon_vma is attached to the VMA, collapse_and_free_pmd() requires
it to be locked.

Page table traversal is allowed under any one of the mmap lock, the
anon_vma lock (if the VMA is associated with an anon_vma), and the
mapping lock (if the VMA is associated with a mapping); and so to be
able to remove page tables, we must hold all three of them. 
retract_page_tables() bails out if an ->anon_vma is attached, but does
this check before holding the mmap lock (as the comment above the check
explains).

If we racily merged an existing ->anon_vma (shared with a child
process) from a neighboring VMA, subsequent rmap traversals on pages
belonging to the child will be able to see the page tables that we are
concurrently removing while assuming that nothing else can access them.

Repeat the ->anon_vma check once we hold the mmap lock to ensure that
there really is no concurrent page table access.

Hitting this bug causes a lockdep warning in collapse_and_free_pmd(),
in the line "lockdep_assert_held_write(&vma->anon_vma->root->rwsem)". 
It can also lead to use-after-free access.

Link: https://lore.kernel.org/linux-mm/CAG48ez3434wZBKFFbdx4M9j6eUwSUVPd4dxhzW_k_POneSDF+A@mail.gmail.com/
Link: https://lkml.kernel.org/r/20230111133351.807024-1-jannh@google.com
Fixes: f3f0e1d215 ("khugepaged: add support of collapse for tmpfs/shmem pages")
Signed-off-by: Jann Horn <jannh@google.com>
Reported-by: Zach O'Keefe <zokeefe@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@intel.linux.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:07 -08:00
Liam Howlett
7327e8111a maple_tree: fix mas_empty_area_rev() lower bound validation
mas_empty_area_rev() was not correctly validating the start of a gap
against the lower limit.  This could lead to the range starting lower than
the requested minimum.

Fix the issue by better validating a gap once one is found.

This commit also adds tests to the maple tree test suite for this issue
and tests the mas_empty_area() function for similar bound checking.

Link: https://lkml.kernel.org/r/20230111200136.1851322-1-Liam.Howlett@oracle.com
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216911
Fixes: 54a611b605 ("Maple Tree: add new data structure")
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: <amanieu@gmail.com>
  Link: https://lore.kernel.org/linux-mm/0b9f5425-08d4-8013-aa4c-e620c3b10bb2@leemhuis.info/
Tested-by: Holger Hoffsttte <holger@applied-asynchrony.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31 16:44:07 -08:00
Pengfei Xu
24b5308cf5 selftests/filesystems: grant executable permission to run_fat_tests.sh
When use tools/testing/selftests/kselftest_install.sh to make the
kselftest-list.txt under tools/testing/selftests/kselftest_install.

Then use tools/testing/selftests/kselftest_install/run_kselftest.sh to run
all the kselftests in kselftest-list.txt, it will be blocked by case
"filesystems/fat: run_fat_tests.sh" with "Warning: file run_fat_tests.sh
is not executable", so grant executable permission to run_fat_tests.sh to
fix this issue.

Link: https://lkml.kernel.org/r/dfdbba6df8a1ab34bb1e81cd8bd7ca3f9ed5c369.1673424747.git.pengfei.xu@intel.com
Fixes: dd7c9be330 ("selftests/filesystems: add a vfat RENAME_EXCHANGE test")
Signed-off-by: Pengfei Xu <pengfei.xu@intel.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-19 17:27:25 -08:00
Peter Xu
0ca2c535f5 selftests/vm: remove __USE_GNU in hugetlb-madvise.c
__USE_GNU should be an internal macro only used inside glibc.  Either
memfd_create() or fallocate() requires _GNU_SOURCE per man page, where
__USE_GNU will further be defined by glibc headers include/features.h:

  #ifdef _GNU_SOURCE
  # define __USE_GNU	1
  #endif

This fixes:

   >> hugetlb-madvise.c:20: warning: "__USE_GNU" redefined
      20 | #define __USE_GNU
         |
   In file included from /usr/include/x86_64-linux-gnu/bits/libc-header-start.h:33,
                    from /usr/include/stdlib.h:26,
                    from hugetlb-madvise.c:16:
   /usr/include/features.h:407: note: this is the location of the previous definition
     407 | # define __USE_GNU      1
         |

Link: https://lkml.kernel.org/r/Y8V9z+z6Tk7NetI3@x1n
Signed-off-by: Peter Xu <peterx@redhat.com>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18 17:20:52 -08:00
Björn Töpel
9a3f21fe5c selftests: vm: enable cross-compilation
Selftests vm builds break when doing cross-compilation.  The Makefile
MACHINE variable incorrectly picks upp the host machine architecture.

If the CROSS_COMPILE variable is set, dig out the target host architecture
from CROSS_COMPILE, instead of calling uname.

Link: https://lkml.kernel.org/r/20230109114251.3349638-1-bjorn@kernel.org
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18 17:12:59 -08:00
Alexander Pantyukhin
d526643f15 tools:cgroup:memcg_shrinker remove redundant import
Remove redundant import of the sys module.

Also use the sort function instead of sorted.  It sorts the direct array
without create the new one in memory.

Link: https://lkml.kernel.org/r/20230108105023.4289-1-apantykhin@gmail.com
Signed-off-by: Alexander Pantyukhin <apantykhin@gmail.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18 17:12:59 -08:00
Xu Panda
b6f00c9190 mm/damon/sysfs-schemes: use strscpy() to instead of strncpy()
The implementation of strscpy() is more robust and safer.
That's now the recommended way to copy NUL-terminated strings.

Link: https://lkml.kernel.org/r/202301091946553770006@zte.com.cn
Signed-off-by: Xu Panda <xu.panda@zte.com.cn>
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18 17:12:59 -08:00
Vishal Moola (Oracle)
e8dfc854ee ext4: convert mext_page_double_lock() to mext_folio_double_lock()
Convert mext_page_double_lock() to use folios.  This change saves 146
bytes of kernel text.  It also removes 6 calls to compound_head() and 2
calls to folio_file_page().

Link: https://lkml.kernel.org/r/20221207181009.4016-1-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18 17:12:59 -08:00
David Hildenbrand
f4d9139f13 selftests/mm: define MADV_PAGEOUT to fix compilation issues
If MADV_PAGEOUT is not defined (e.g., on AlmaLinux 8), compilation will
fail.  Let's fix that like khugepaged.c does by conditionally defining
MADV_PAGEOUT.

Link: https://lkml.kernel.org/r/20230109171255.488749-1-david@redhat.com
Fixes: 69c66add56 ("selftests/vm: anon_cow: test COW handling of anonymous memory")
Signed-off-by: David Hildenbrand <david@redhat.com>
Reported-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18 17:12:59 -08:00
Frank van der Linden
c4876ff687 mm/debug: use valid physical memory for pmd/pud tests
The page table debug tests need a physical address to validate low-level
page table manipulation with.  The memory at this address is not actually
touched, it just encoded in the page table entries at various levels
during the tests only.

Since the memory is not used, the code just picks the physical address of
the start_kernel symbol.  This value is then truncated to get a properly
aligned address that is to be used for various tests.  Because of the
truncation, the address might not actually exist, or might not describe a
complete huge page.  That's not a problem for most tests, but the
arch-specific code may check for attribute validity and consistency.  The
x86 version of {pud,pmd}_set_huge actually validates the MTRRs for the
PMD/PUD range.  This may fail with an address derived from start_kernel,
depending on where the kernel was loaded and what the physical memory
layout of the system is.  This then leads to false negatives for the
{pud,pmd}_set_huge tests.

Avoid this by finding a properly aligned memory range that exists and is
usable.  If such a range is not found, skip the tests that needed it.

[fvdl@google.com: v3]
  Link: https://lkml.kernel.org/r/20230110181208.1633879-1-fvdl@google.com
Link: https://lkml.kernel.org/r/20230109174332.329366-1-fvdl@google.com
Fixes: 399145f9eb ("mm/debug: add tests validating architecture page table helpers")
Signed-off-by: Frank van der Linden <fvdl@google.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18 17:12:59 -08:00
SeongJae Park
b0c0e744e8 mm/damon/paddr: remove damon_pa_access_chk_result struct
'damon_pa_access_chk_result' struct contains only one field.  Use a
variable instead.

Link: https://lkml.kernel.org/r/20230109213335.62525-7-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18 17:12:58 -08:00
SeongJae Park
397b0c3a58 mm/damon/paddr: remove folio_sz field from damon_pa_access_chk_result
DAMON physical address space monitoring operations set gets and saves size
of the folio for a given physical address inside rmap walks, but it can be
directly caluclated outside of the walks.  Remove the 'folio_sz' field
from 'damon_pa_access_chk_result struct' and calculate the size directly
from outside of the walks.

Link: https://lkml.kernel.org/r/20230109213335.62525-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18 17:12:58 -08:00