Commit Graph

1310742 Commits

Author SHA1 Message Date
Jann Horn
a4a282daf1 mm/mremap: fix address wraparound in move_page_tables()
On 32-bit platforms, it is possible for the expression `len + old_addr <
old_end` to be false-positive if `len + old_addr` wraps around. 
`old_addr` is the cursor in the old range up to which page table entries
have been moved; so if the operation succeeded, `old_addr` is the *end* of
the old region, and adding `len` to it can wrap.

The overflow causes mremap() to mistakenly believe that PTEs have been
copied; the consequence is that mremap() bails out, but doesn't move the
PTEs back before the new VMA is unmapped, causing anonymous pages in the
region to be lost.  So basically if userspace tries to mremap() a
private-anon region and hits this bug, mremap() will return an error and
the private-anon region's contents appear to have been zeroed.

The idea of this check is that `old_end - len` is the original start
address, and writing the check that way also makes it easier to read; so
fix the check by rearranging the comparison accordingly.

(An alternate fix would be to refactor this function by introducing an
"orig_old_start" variable or such.)


Tested in a VM with a 32-bit X86 kernel; without the patch:

```
user@horn:~/big_mremap$ cat test.c
#define _GNU_SOURCE
#include <stdlib.h>
#include <stdio.h>
#include <err.h>
#include <sys/mman.h>

#define ADDR1 ((void*)0x60000000)
#define ADDR2 ((void*)0x10000000)
#define SIZE          0x50000000uL

int main(void) {
  unsigned char *p1 = mmap(ADDR1, SIZE, PROT_READ|PROT_WRITE,
      MAP_ANONYMOUS|MAP_PRIVATE|MAP_FIXED_NOREPLACE, -1, 0);
  if (p1 == MAP_FAILED)
    err(1, "mmap 1");
  unsigned char *p2 = mmap(ADDR2, SIZE, PROT_NONE,
      MAP_ANONYMOUS|MAP_PRIVATE|MAP_FIXED_NOREPLACE, -1, 0);
  if (p2 == MAP_FAILED)
    err(1, "mmap 2");
  *p1 = 0x41;
  printf("first char is 0x%02hhx\n", *p1);
  unsigned char *p3 = mremap(p1, SIZE, SIZE,
      MREMAP_MAYMOVE|MREMAP_FIXED, p2);
  if (p3 == MAP_FAILED) {
    printf("mremap() failed; first char is 0x%02hhx\n", *p1);
  } else {
    printf("mremap() succeeded; first char is 0x%02hhx\n", *p3);
  }
}
user@horn:~/big_mremap$ gcc -static -o test test.c
user@horn:~/big_mremap$ setarch -R ./test
first char is 0x41
mremap() failed; first char is 0x00
```

With the patch:

```
user@horn:~/big_mremap$ setarch -R ./test
first char is 0x41
mremap() succeeded; first char is 0x41
```

Link: https://lkml.kernel.org/r/20241111-fix-mremap-32bit-wrap-v1-1-61d6be73b722@google.com
Fixes: af8ca1c149 ("mm/mremap: optimize the start addresses in move_page_tables()")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Qi Zheng <zhengqi.arch@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-14 22:43:48 -08:00
Motiejus JakÅ`tys
a39326767c tools/mm: fix compile error
Add a missing semicolon.

Link: https://lkml.kernel.org/r/20241112171655.1662670-1-motiejus@jakstys.lt
Fixes: ece5897e5a ("tools/mm: -Werror fixes in page-types/slabinfo")
Signed-off-by: Motiejus JakÅ`tys <motiejus@jakstys.lt>
Closes: https://github.com/NixOS/nixpkgs/issues/355369
Reviewed-by: SeongJae Park <sj@kernel.org>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Cc: Wladislav Wiebe <wladislav.kw@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-14 22:43:48 -08:00
Kairui Song
0ec8bc9e88 mm, swap: fix allocation and scanning race with swapoff
There are two flags used to synchronize allocation and scanning with
swapoff: SWP_WRITEOK and SWP_SCANNING.

SWP_WRITEOK: Swapoff will first unset this flag, at this point any further
swap allocation or scanning on this device should just abort so no more
new entries will be referencing this device.  Swapoff will then unuse all
existing swap entries.

SWP_SCANNING: This flag is set when device is being scanned.  Swapoff will
wait for all scanner to stop before the final release of the swap device
structures to avoid UAF.  Note this flag is the highest used bit of
si->flags so it could be added up arithmetically, if there are multiple
scanner.

commit 5f843a9a3a ("mm: swap: separate SSD allocation from
scan_swap_map_slots()") ignored SWP_SCANNING and SWP_WRITEOK flags while
separating cluster allocation path from the old allocation path.  Add the
flags back to fix swapoff race.  The race is hard to trigger as si->lock
prevents most parallel operations, but si->lock could be dropped for
reclaim or discard.  This issue is found during code review.

This commit fixes this problem.  For SWP_SCANNING, Just like before, set
the flag before scan and remove it afterwards.

For SWP_WRITEOK, there are several places where si->lock could be dropped,
it will be error-prone and make the code hard to follow if we try to cover
these places one by one.  So just do one check before the real allocation,
which is also very similar like before.  With new cluster allocator it may
waste a bit of time iterating the clusters but won't take long, and
swapoff is not performance sensitive.

Link: https://lkml.kernel.org/r/20241112083414.78174-1-ryncsn@gmail.com
Fixes: 5f843a9a3a ("mm: swap: separate SSD allocation from scan_swap_map_slots()")
Reported-by: "Huang, Ying" <ying.huang@intel.com>
Closes: https://lore.kernel.org/linux-mm/87a5es3f1f.fsf@yhuang6-desk2.ccr.corp.intel.com/
Signed-off-by: Kairui Song <kasong@tencent.com>
Cc: Barry Song <v-songbaohua@oppo.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-14 15:25:07 -08:00
Johannes Weiner
dcf32ea7ec mm: swapfile: fix cluster reclaim work crash on rotational devices
syzbot and Daan report a NULL pointer crash in the new full swap cluster
reclaim work:

> Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI
> KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
> CPU: 1 UID: 0 PID: 51 Comm: kworker/1:1 Not tainted 6.12.0-rc6-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
> Workqueue: events swap_reclaim_work
> RIP: 0010:__list_del_entry_valid_or_report+0x20/0x1c0 lib/list_debug.c:49
> Code: 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 89 fe 48 83 c7 08 48 83 ec 18 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 19 01 00 00 48 89 f2 48 8b 4e 08 48 b8 00 00 00
> RSP: 0018:ffffc90000bb7c30 EFLAGS: 00010202
> RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff88807b9ae078
> RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000008
> RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
> R10: 0000000000000001 R11: 000000000000004f R12: dffffc0000000000
> R13: ffffffffffffffb8 R14: ffff88807b9ae000 R15: ffffc90003af1000
> FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007fffaca68fb8 CR3: 00000000791c8000 CR4: 00000000003526f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
>  <TASK>
>  __list_del_entry_valid include/linux/list.h:124 [inline]
>  __list_del_entry include/linux/list.h:215 [inline]
>  list_move_tail include/linux/list.h:310 [inline]
>  swap_reclaim_full_clusters+0x109/0x460 mm/swapfile.c:748
>  swap_reclaim_work+0x2e/0x40 mm/swapfile.c:779

The syzbot console output indicates a virtual environment where swapfile
is on a rotational device.  In this case, clusters aren't actually used,
and si->full_clusters is not initialized.  Daan's report is from qemu, so
likely rotational too.

Make sure to only schedule the cluster reclaim work when clusters are
actually in use.

Link: https://lkml.kernel.org/r/20241107142335.GB1172372@cmpxchg.org
Link: https://lore.kernel.org/lkml/672ac50b.050a0220.2edce.1517.GAE@google.com/
Link: https://github.com/systemd/systemd/issues/35044
Fixes: 5168a68eb7 ("mm, swap: avoid over reclaim of full clusters")
Reported-by: syzbot+078be8bfa863cb9e0c6b@syzkaller.appspotmail.com
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Cc: Kairui Song <ryncsn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-12 16:01:36 -08:00
Donet Tom
fae1980347 selftests: hugetlb_dio: fixup check for initial conditions to skip in the start
This test verifies that a hugepage, used as a user buffer for DIO
operations, is correctly freed upon unmapping.  To test this, we read the
count of free hugepages before and after the mmap, DIO, and munmap
operations, then check if the free hugepage count is the same.

Reading free hugepages before the test was removed by commit 0268d45799
('selftests: hugetlb_dio: check for initial conditions to skip at the
start'), causing the test to always fail.

This patch adds back reading the free hugepages before starting the test. 
With this patch, the tests are now passing.

Test results without this patch:

./tools/testing/selftests/mm/hugetlb_dio
TAP version 13
1..4
 # No. Free pages before allocation : 0
 # No. Free pages after munmap : 100
not ok 1 : Huge pages not freed!
 # No. Free pages before allocation : 0
 # No. Free pages after munmap : 100
not ok 2 : Huge pages not freed!
 # No. Free pages before allocation : 0
 # No. Free pages after munmap : 100
not ok 3 : Huge pages not freed!
 # No. Free pages before allocation : 0
 # No. Free pages after munmap : 100
not ok 4 : Huge pages not freed!
 # Totals: pass:0 fail:4 xfail:0 xpass:0 skip:0 error:0

Test results with this patch:

/tools/testing/selftests/mm/hugetlb_dio
TAP version 13
1..4
# No. Free pages before allocation : 100
# No. Free pages after munmap : 100
ok 1 : Huge pages freed successfully !
# No. Free pages before allocation : 100
# No. Free pages after munmap : 100
ok 2 : Huge pages freed successfully !
# No. Free pages before allocation : 100
# No. Free pages after munmap : 100
ok 3 : Huge pages freed successfully !
# No. Free pages before allocation : 100
# No. Free pages after munmap : 100
ok 4 : Huge pages freed successfully !

# Totals: pass:4 fail:0 xfail:0 xpass:0 skip:0 error:0

Link: https://lkml.kernel.org/r/20241110064903.23626-1-donettom@linux.ibm.com
Fixes: 0268d45799 ("selftests: hugetlb_dio: check for initial conditions to skip in the start")
Signed-off-by: Donet Tom <donettom@linux.ibm.com>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-12 10:14:00 -08:00
Hugh Dickins
a3477c9e02 mm/thp: fix deferred split queue not partially_mapped: fix
Though even more elusive than before, list_del corruption has still been
seen on THP's deferred split queue.

The idea in commit e66f3185fa was right, but its implementation wrong. 
The context omitted an important comment just before the critical test:
"split_folio() removes folio from list on success." In ignoring that
comment, when a THP split succeeded, the code went on to release the
preceding safe folio, preserving instead an irrelevant (formerly head)
folio: which gives no safety because it's not on the list.  Fix the logic.

Link: https://lkml.kernel.org/r/3c995a30-31ce-0998-1b9f-3a2cb9354c91@google.com
Fixes: e66f3185fa ("mm/thp: fix deferred split queue not partially_mapped")
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Usama Arif <usamaarif642@gmail.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-12 10:14:00 -08:00
John Hubbard
94efde1d15 mm/gup: avoid an unnecessary allocation call for FOLL_LONGTERM cases
commit 53ba78de06 ("mm/gup: introduce
check_and_migrate_movable_folios()") created a new constraint on the
pin_user_pages*() API family: a potentially large internal allocation must
now occur, for FOLL_LONGTERM cases.

A user-visible consequence has now appeared: user space can no longer pin
more than 2GB of memory anymore on x86_64.  That's because, on a 4KB
PAGE_SIZE system, when user space tries to (indirectly, via a device
driver that calls pin_user_pages()) pin 2GB, this requires an allocation
of a folio pointers array of MAX_PAGE_ORDER size, which is the limit for
kmalloc().

In addition to the directly visible effect described above, there is also
the problem of adding an unnecessary allocation.  The **pages array
argument has already been allocated, and there is no need for a redundant
**folios array allocation in this case.

Fix this by avoiding the new allocation entirely.  This is done by
referring to either the original page[i] within **pages, or to the
associated folio.  Thanks to David Hildenbrand for suggesting this
approach and for providing the initial implementation (which I've tested
and adjusted slightly) as well.

[jhubbard@nvidia.com: whitespace tweak, per David]
  Link: https://lkml.kernel.org/r/131cf9c8-ebc0-4cbb-b722-22fa8527bf3c@nvidia.com
[jhubbard@nvidia.com: bypass pofs_get_folio(), per Oscar]
  Link: https://lkml.kernel.org/r/c1587c7f-9155-45be-bd62-1e36c0dd6923@nvidia.com
Link: https://lkml.kernel.org/r/20241105032944.141488-2-jhubbard@nvidia.com
Fixes: 53ba78de06 ("mm/gup: introduce check_and_migrate_movable_folios()")
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Vivek Kasireddy <vivek.kasireddy@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dongwon Kim <dongwon.kim@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Junxiao Chang <junxiao.chang@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-12 10:14:00 -08:00
Hajime Tazaki
247d720b2c nommu: pass NULL argument to vma_iter_prealloc()
When deleting a vma entry from a maple tree, it has to pass NULL to
vma_iter_prealloc() in order to calculate internal state of the tree, but
it passed a wrong argument.  As a result, nommu kernels crashed upon
accessing a vma iterator, such as acct_collect() reading the size of vma
entries after do_munmap().

This commit fixes this issue by passing a right argument to the
preallocation call.

Link: https://lkml.kernel.org/r/20241108222834.3625217-1-thehajime@gmail.com
Fixes: b5df092264 ("mm: set up vma iterator for vma_iter_prealloc() calls")
Signed-off-by: Hajime Tazaki <thehajime@gmail.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-11 17:20:23 -08:00
Dmitry Antipov
23aab03710 ocfs2: fix UBSAN warning in ocfs2_verify_volume()
Syzbot has reported the following splat triggered by UBSAN:

UBSAN: shift-out-of-bounds in fs/ocfs2/super.c:2336:10
shift exponent 32768 is too large for 32-bit type 'int'
CPU: 2 UID: 0 PID: 5255 Comm: repro Not tainted 6.12.0-rc4-syzkaller-00047-gc2ee9f594da8 #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x241/0x360
 ? __pfx_dump_stack_lvl+0x10/0x10
 ? __pfx__printk+0x10/0x10
 ? __asan_memset+0x23/0x50
 ? lockdep_init_map_type+0xa1/0x910
 __ubsan_handle_shift_out_of_bounds+0x3c8/0x420
 ocfs2_fill_super+0xf9c/0x5750
 ? __pfx_ocfs2_fill_super+0x10/0x10
 ? __pfx_validate_chain+0x10/0x10
 ? __pfx_validate_chain+0x10/0x10
 ? validate_chain+0x11e/0x5920
 ? __lock_acquire+0x1384/0x2050
 ? __pfx_validate_chain+0x10/0x10
 ? string+0x26a/0x2b0
 ? widen_string+0x3a/0x310
 ? string+0x26a/0x2b0
 ? bdev_name+0x2b1/0x3c0
 ? pointer+0x703/0x1210
 ? __pfx_pointer+0x10/0x10
 ? __pfx_format_decode+0x10/0x10
 ? __lock_acquire+0x1384/0x2050
 ? vsnprintf+0x1ccd/0x1da0
 ? snprintf+0xda/0x120
 ? __pfx_lock_release+0x10/0x10
 ? do_raw_spin_lock+0x14f/0x370
 ? __pfx_snprintf+0x10/0x10
 ? set_blocksize+0x1f9/0x360
 ? sb_set_blocksize+0x98/0xf0
 ? setup_bdev_super+0x4e6/0x5d0
 mount_bdev+0x20c/0x2d0
 ? __pfx_ocfs2_fill_super+0x10/0x10
 ? __pfx_mount_bdev+0x10/0x10
 ? vfs_parse_fs_string+0x190/0x230
 ? __pfx_vfs_parse_fs_string+0x10/0x10
 legacy_get_tree+0xf0/0x190
 ? __pfx_ocfs2_mount+0x10/0x10
 vfs_get_tree+0x92/0x2b0
 do_new_mount+0x2be/0xb40
 ? __pfx_do_new_mount+0x10/0x10
 __se_sys_mount+0x2d6/0x3c0
 ? __pfx___se_sys_mount+0x10/0x10
 ? do_syscall_64+0x100/0x230
 ? __x64_sys_mount+0x20/0xc0
 do_syscall_64+0xf3/0x230
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f37cae96fda
Code: 48 8b 0d 51 ce 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 1e ce 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007fff6c1aa228 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fff6c1aa240 RCX: 00007f37cae96fda
RDX: 00000000200002c0 RSI: 0000000020000040 RDI: 00007fff6c1aa240
RBP: 0000000000000004 R08: 00007fff6c1aa280 R09: 0000000000000000
R10: 00000000000008c0 R11: 0000000000000206 R12: 00000000000008c0
R13: 00007fff6c1aa280 R14: 0000000000000003 R15: 0000000001000000
 </TASK>

For a really damaged superblock, the value of 'i_super.s_blocksize_bits'
may exceed the maximum possible shift for an underlying 'int'.  So add an
extra check whether the aforementioned field represents the valid block
size, which is 512 bytes, 1K, 2K, or 4K.

Link: https://lkml.kernel.org/r/20241106092100.2661330-1-dmantipov@yandex.ru
Fixes: ccd979bdbc ("[PATCH] OCFS2: The Second Oracle Cluster Filesystem")
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Reported-by: syzbot+56f7cd1abe4b8e475180@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=56f7cd1abe4b8e475180
Reviewed-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: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-11 17:20:23 -08:00
Ryusuke Konishi
2026559a6c nilfs2: fix null-ptr-deref in block_dirty_buffer tracepoint
When using the "block:block_dirty_buffer" tracepoint, mark_buffer_dirty()
may cause a NULL pointer dereference, or a general protection fault when
KASAN is enabled.

This happens because, since the tracepoint was added in
mark_buffer_dirty(), it references the dev_t member bh->b_bdev->bd_dev
regardless of whether the buffer head has a pointer to a block_device
structure.

In the current implementation, nilfs_grab_buffer(), which grabs a buffer
to read (or create) a block of metadata, including b-tree node blocks,
does not set the block device, but instead does so only if the buffer is
not in the "uptodate" state for each of its caller block reading
functions.  However, if the uptodate flag is set on a folio/page, and the
buffer heads are detached from it by try_to_free_buffers(), and new buffer
heads are then attached by create_empty_buffers(), the uptodate flag may
be restored to each buffer without the block device being set to
bh->b_bdev, and mark_buffer_dirty() may be called later in that state,
resulting in the bug mentioned above.

Fix this issue by making nilfs_grab_buffer() always set the block device
of the super block structure to the buffer head, regardless of the state
of the buffer's uptodate flag.

Link: https://lkml.kernel.org/r/20241106160811.3316-3-konishi.ryusuke@gmail.com
Fixes: 5305cb8308 ("block: add block_{touch|dirty}_buffer tracepoint")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ubisectech Sirius <bugreport@valiantsec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-11 17:20:23 -08:00
Ryusuke Konishi
cd45e963e4 nilfs2: fix null-ptr-deref in block_touch_buffer tracepoint
Patch series "nilfs2: fix null-ptr-deref bugs on block tracepoints".

This series fixes null pointer dereference bugs that occur when using
nilfs2 and two block-related tracepoints.


This patch (of 2):

It has been reported that when using "block:block_touch_buffer"
tracepoint, touch_buffer() called from __nilfs_get_folio_block() causes a
NULL pointer dereference, or a general protection fault when KASAN is
enabled.

This happens because since the tracepoint was added in touch_buffer(), it
references the dev_t member bh->b_bdev->bd_dev regardless of whether the
buffer head has a pointer to a block_device structure.  In the current
implementation, the block_device structure is set after the function
returns to the caller.

Here, touch_buffer() is used to mark the folio/page that owns the buffer
head as accessed, but the common search helper for folio/page used by the
caller function was optimized to mark the folio/page as accessed when it
was reimplemented a long time ago, eliminating the need to call
touch_buffer() here in the first place.

So this solves the issue by eliminating the touch_buffer() call itself.

Link: https://lkml.kernel.org/r/20241106160811.3316-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20241106160811.3316-2-konishi.ryusuke@gmail.com
Fixes: 5305cb8308 ("block: add block_{touch|dirty}_buffer tracepoint")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: Ubisectech Sirius <bugreport@valiantsec.com>
Closes: https://lkml.kernel.org/r/86bd3013-887e-4e38-960f-ca45c657f032.bugreport@valiantsec.com
Reported-by: syzbot+9982fb8d18eba905abe2@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=9982fb8d18eba905abe2
Tested-by: syzbot+9982fb8d18eba905abe2@syzkaller.appspotmail.com
Cc: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-11 17:20:23 -08:00
Roman Gushchin
66edc3a589 mm: page_alloc: move mlocked flag clearance into free_pages_prepare()
Syzbot reported a bad page state problem caused by a page being freed
using free_page() still having a mlocked flag at free_pages_prepare()
stage:

  BUG: Bad page state in process syz.5.504  pfn:61f45
  page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x61f45
  flags: 0xfff00000080204(referenced|workingset|mlocked|node=0|zone=1|lastcpupid=0x7ff)
  raw: 00fff00000080204 0000000000000000 dead000000000122 0000000000000000
  raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
  page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
  page_owner tracks the page as allocated
  page last allocated via order 0, migratetype Unmovable, gfp_mask 0x400dc0(GFP_KERNEL_ACCOUNT|__GFP_ZERO), pid 8443, tgid 8442 (syz.5.504), ts 201884660643, free_ts 201499827394
   set_page_owner include/linux/page_owner.h:32 [inline]
   post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537
   prep_new_page mm/page_alloc.c:1545 [inline]
   get_page_from_freelist+0x303f/0x3190 mm/page_alloc.c:3457
   __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4733
   alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
   kvm_coalesced_mmio_init+0x1f/0xf0 virt/kvm/coalesced_mmio.c:99
   kvm_create_vm virt/kvm/kvm_main.c:1235 [inline]
   kvm_dev_ioctl_create_vm virt/kvm/kvm_main.c:5488 [inline]
   kvm_dev_ioctl+0x12dc/0x2240 virt/kvm/kvm_main.c:5530
   __do_compat_sys_ioctl fs/ioctl.c:1007 [inline]
   __se_compat_sys_ioctl+0x510/0xc90 fs/ioctl.c:950
   do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
   __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386
   do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411
   entry_SYSENTER_compat_after_hwframe+0x84/0x8e
  page last free pid 8399 tgid 8399 stack trace:
   reset_page_owner include/linux/page_owner.h:25 [inline]
   free_pages_prepare mm/page_alloc.c:1108 [inline]
   free_unref_folios+0xf12/0x18d0 mm/page_alloc.c:2686
   folios_put_refs+0x76c/0x860 mm/swap.c:1007
   free_pages_and_swap_cache+0x5c8/0x690 mm/swap_state.c:335
   __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
   tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
   tlb_flush_mmu_free mm/mmu_gather.c:366 [inline]
   tlb_flush_mmu+0x3a3/0x680 mm/mmu_gather.c:373
   tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:465
   exit_mmap+0x496/0xc40 mm/mmap.c:1926
   __mmput+0x115/0x390 kernel/fork.c:1348
   exit_mm+0x220/0x310 kernel/exit.c:571
   do_exit+0x9b2/0x28e0 kernel/exit.c:926
   do_group_exit+0x207/0x2c0 kernel/exit.c:1088
   __do_sys_exit_group kernel/exit.c:1099 [inline]
   __se_sys_exit_group kernel/exit.c:1097 [inline]
   __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1097
   x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232
   do_syscall_x64 arch/x86/entry/common.c:52 [inline]
   do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
   entry_SYSCALL_64_after_hwframe+0x77/0x7f
  Modules linked in:
  CPU: 0 UID: 0 PID: 8442 Comm: syz.5.504 Not tainted 6.12.0-rc6-syzkaller #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
  Call Trace:
   <TASK>
   __dump_stack lib/dump_stack.c:94 [inline]
   dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
   bad_page+0x176/0x1d0 mm/page_alloc.c:501
   free_page_is_bad mm/page_alloc.c:918 [inline]
   free_pages_prepare mm/page_alloc.c:1100 [inline]
   free_unref_page+0xed0/0xf20 mm/page_alloc.c:2638
   kvm_destroy_vm virt/kvm/kvm_main.c:1327 [inline]
   kvm_put_kvm+0xc75/0x1350 virt/kvm/kvm_main.c:1386
   kvm_vcpu_release+0x54/0x60 virt/kvm/kvm_main.c:4143
   __fput+0x23f/0x880 fs/file_table.c:431
   task_work_run+0x24f/0x310 kernel/task_work.c:239
   exit_task_work include/linux/task_work.h:43 [inline]
   do_exit+0xa2f/0x28e0 kernel/exit.c:939
   do_group_exit+0x207/0x2c0 kernel/exit.c:1088
   __do_sys_exit_group kernel/exit.c:1099 [inline]
   __se_sys_exit_group kernel/exit.c:1097 [inline]
   __ia32_sys_exit_group+0x3f/0x40 kernel/exit.c:1097
   ia32_sys_call+0x2624/0x2630 arch/x86/include/generated/asm/syscalls_32.h:253
   do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
   __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386
   do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411
   entry_SYSENTER_compat_after_hwframe+0x84/0x8e
  RIP: 0023:0xf745d579
  Code: Unable to access opcode bytes at 0xf745d54f.
  RSP: 002b:00000000f75afd6c EFLAGS: 00000206 ORIG_RAX: 00000000000000fc
  RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: 00000000ffffff9c RDI: 00000000f744cff4
  RBP: 00000000f717ae61 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
  R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
   </TASK>

The problem was originally introduced by commit b109b87050 ("mm/munlock:
replace clear_page_mlock() by final clearance"): it was focused on
handling pagecache and anonymous memory and wasn't suitable for lower
level get_page()/free_page() API's used for example by KVM, as with this
reproducer.

Fix it by moving the mlocked flag clearance down to free_page_prepare().

The bug itself if fairly old and harmless (aside from generating these
warnings), aside from a small memory leak - "bad" pages are stopped from
being allocated again.

Link: https://lkml.kernel.org/r/20241106195354.270757-1-roman.gushchin@linux.dev
Fixes: b109b87050 ("mm/munlock: replace clear_page_mlock() by final clearance")
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Reported-by: syzbot+e985d3026c4fd041578e@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/6729f475.050a0220.701a.0019.GAE@google.com
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-11 17:20:23 -08:00
Barry Song
e7ac4daeed mm: count zeromap read and set for swapout and swapin
When the proportion of folios from the zeromap is small, missing their
accounting may not significantly impact profiling.  However, it's easy to
construct a scenario where this becomes an issue—for example, allocating
1 GB of memory, writing zeros from userspace, followed by MADV_PAGEOUT,
and then swapping it back in.  In this case, the swap-out and swap-in
counts seem to vanish into a black hole, potentially causing semantic
ambiguity.

On the other hand, Usama reported that zero-filled pages can exceed 10% in
workloads utilizing zswap, while Hailong noted that some app in Android
have more than 6% zero-filled pages.  Before commit 0ca0c24e32 ("mm:
store zero pages to be swapped out in a bitmap"), both zswap and zRAM
implemented similar optimizations, leading to these optimized-out pages
being counted in either zswap or zRAM counters (with pswpin/pswpout also
increasing for zRAM).  With zeromap functioning prior to both zswap and
zRAM, userspace will no longer detect these swap-out and swap-in actions.

We have three ways to address this:

1. Introduce a dedicated counter specifically for the zeromap.

2. Use pswpin/pswpout accounting, treating the zero map as a standard
   backend.  This approach aligns with zRAM's current handling of
   same-page fills at the device level.  However, it would mean losing the
   optimized-out page counters previously available in zRAM and would not
   align with systems using zswap.  Additionally, as noted by Nhat Pham,
   pswpin/pswpout counters apply only to I/O done directly to the backend
   device.

3. Count zeromap pages under zswap, aligning with system behavior when
   zswap is enabled.  However, this would not be consistent with zRAM, nor
   would it align with systems lacking both zswap and zRAM.

Given the complications with options 2 and 3, this patch selects
option 1.

We can find these counters from /proc/vmstat (counters for the whole
system) and memcg's memory.stat (counters for the interested memcg).

For example:

$ grep -E 'swpin_zero|swpout_zero' /proc/vmstat
swpin_zero 1648
swpout_zero 33536

$ grep -E 'swpin_zero|swpout_zero' /sys/fs/cgroup/system.slice/memory.stat
swpin_zero 3905
swpout_zero 3985

This patch does not address any specific zeromap bug, but the missing
swpout and swpin counts for zero-filled pages can be highly confusing and
may mislead user-space agents that rely on changes in these counters as
indicators.  Therefore, we add a Fixes tag to encourage the inclusion of
this counter in any kernel versions with zeromap.

Many thanks to Kanchana for the contribution of changing
count_objcg_event() to count_objcg_events() to support large folios[1],
which has now been incorporated into this patch.

[1] https://lkml.kernel.org/r/20241001053222.6944-5-kanchana.p.sridhar@intel.com

Link: https://lkml.kernel.org/r/20241107011246.59137-1-21cnbao@gmail.com
Fixes: 0ca0c24e32 ("mm: store zero pages to be swapped out in a bitmap")
Co-developed-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: Hailong Liu <hailong.liu@oppo.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-11 00:00:37 -08:00
Thorsten Blum
c289f4de8e mailmap: add entry for Thorsten Blum
Map my previously used email address to my @linux.dev address.

Link: https://lkml.kernel.org/r/20241103234411.2522-2-thorsten.blum@linux.dev
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Cc: Alex Elder <elder@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Geliang Tang <geliang@kernel.org>
Cc: Kees Cook <kees@kernel.org>
Cc: Mathieu Othacehe <m.othacehe@gmail.com>
Cc: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Cc: Matt Ranostay <matt@ranostay.sg>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
Cc: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:59 -08:00
Andrew Kanner
0b63c0e01f ocfs2: remove entry once instead of null-ptr-dereference in ocfs2_xa_remove()
Syzkaller is able to provoke null-ptr-dereference in ocfs2_xa_remove():

[   57.319872] (a.out,1161,7):ocfs2_xa_remove:2028 ERROR: status = -12
[   57.320420] (a.out,1161,7):ocfs2_xa_cleanup_value_truncate:1999 ERROR: Partial truncate while removing xattr overlay.upper.  Leaking 1 clusters and removing the entry
[   57.321727] BUG: kernel NULL pointer dereference, address: 0000000000000004
[...]
[   57.325727] RIP: 0010:ocfs2_xa_block_wipe_namevalue+0x2a/0xc0
[...]
[   57.331328] Call Trace:
[   57.331477]  <TASK>
[...]
[   57.333511]  ? do_user_addr_fault+0x3e5/0x740
[   57.333778]  ? exc_page_fault+0x70/0x170
[   57.334016]  ? asm_exc_page_fault+0x2b/0x30
[   57.334263]  ? __pfx_ocfs2_xa_block_wipe_namevalue+0x10/0x10
[   57.334596]  ? ocfs2_xa_block_wipe_namevalue+0x2a/0xc0
[   57.334913]  ocfs2_xa_remove_entry+0x23/0xc0
[   57.335164]  ocfs2_xa_set+0x704/0xcf0
[   57.335381]  ? _raw_spin_unlock+0x1a/0x40
[   57.335620]  ? ocfs2_inode_cache_unlock+0x16/0x20
[   57.335915]  ? trace_preempt_on+0x1e/0x70
[   57.336153]  ? start_this_handle+0x16c/0x500
[   57.336410]  ? preempt_count_sub+0x50/0x80
[   57.336656]  ? _raw_read_unlock+0x20/0x40
[   57.336906]  ? start_this_handle+0x16c/0x500
[   57.337162]  ocfs2_xattr_block_set+0xa6/0x1e0
[   57.337424]  __ocfs2_xattr_set_handle+0x1fd/0x5d0
[   57.337706]  ? ocfs2_start_trans+0x13d/0x290
[   57.337971]  ocfs2_xattr_set+0xb13/0xfb0
[   57.338207]  ? dput+0x46/0x1c0
[   57.338393]  ocfs2_xattr_trusted_set+0x28/0x30
[   57.338665]  ? ocfs2_xattr_trusted_set+0x28/0x30
[   57.338948]  __vfs_removexattr+0x92/0xc0
[   57.339182]  __vfs_removexattr_locked+0xd5/0x190
[   57.339456]  ? preempt_count_sub+0x50/0x80
[   57.339705]  vfs_removexattr+0x5f/0x100
[...]

Reproducer uses faultinject facility to fail ocfs2_xa_remove() ->
ocfs2_xa_value_truncate() with -ENOMEM.

In this case the comment mentions that we can return 0 if
ocfs2_xa_cleanup_value_truncate() is going to wipe the entry
anyway. But the following 'rc' check is wrong and execution flow do
'ocfs2_xa_remove_entry(loc);' twice:
* 1st: in ocfs2_xa_cleanup_value_truncate();
* 2nd: returning back to ocfs2_xa_remove() instead of going to 'out'.

Fix this by skipping the 2nd removal of the same entry and making
syzkaller repro happy.

Link: https://lkml.kernel.org/r/20241103193845.2940988-1-andrew.kanner@gmail.com
Fixes: 399ff3a748 ("ocfs2: Handle errors while setting external xattr values.")
Signed-off-by: Andrew Kanner <andrew.kanner@gmail.com>
Reported-by: syzbot+386ce9e60fa1b18aac5b@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/671e13ab.050a0220.2b8c0f.01d0.GAE@google.com/T/
Tested-by: syzbot+386ce9e60fa1b18aac5b@syzkaller.appspotmail.com
Reviewed-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: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:59 -08:00
Roman Gushchin
9e05e5c7ee signal: restore the override_rlimit logic
Prior to commit d646969055 ("Reimplement RLIMIT_SIGPENDING on top of
ucounts") UCOUNT_RLIMIT_SIGPENDING rlimit was not enforced for a class of
signals.  However now it's enforced unconditionally, even if
override_rlimit is set.  This behavior change caused production issues.  

For example, if the limit is reached and a process receives a SIGSEGV
signal, sigqueue_alloc fails to allocate the necessary resources for the
signal delivery, preventing the signal from being delivered with siginfo. 
This prevents the process from correctly identifying the fault address and
handling the error.  From the user-space perspective, applications are
unaware that the limit has been reached and that the siginfo is
effectively 'corrupted'.  This can lead to unpredictable behavior and
crashes, as we observed with java applications.

Fix this by passing override_rlimit into inc_rlimit_get_ucounts() and skip
the comparison to max there if override_rlimit is set.  This effectively
restores the old behavior.

Link: https://lkml.kernel.org/r/20241104195419.3962584-1-roman.gushchin@linux.dev
Fixes: d646969055 ("Reimplement RLIMIT_SIGPENDING on top of ucounts")
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Co-developed-by: Andrei Vagin <avagin@google.com>
Signed-off-by: Andrei Vagin <avagin@google.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Alexey Gladkov <legion@kernel.org>
Cc: Kees Cook <kees@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:59 -08:00
Qi Xi
b8ee299855 fs/proc: fix compile warning about variable 'vmcore_mmap_ops'
When build with !CONFIG_MMU, the variable 'vmcore_mmap_ops'
is defined but not used:

>> fs/proc/vmcore.c:458:42: warning: unused variable 'vmcore_mmap_ops'
     458 | static const struct vm_operations_struct vmcore_mmap_ops = {

Fix this by only defining it when CONFIG_MMU is enabled.

Link: https://lkml.kernel.org/r/20241101034803.9298-1-xiqi2@huawei.com
Fixes: 9cb218131d ("vmcore: introduce remap_oldmem_pfn_range()")
Signed-off-by: Qi Xi <xiqi2@huawei.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/lkml/202410301936.GcE8yUos-lkp@intel.com/
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Wang ShaoBo <bobo.shaobowang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:59 -08:00
Andrei Vagin
432dc0654c ucounts: fix counter leak in inc_rlimit_get_ucounts()
The inc_rlimit_get_ucounts() increments the specified rlimit counter and
then checks its limit.  If the value exceeds the limit, the function
returns an error without decrementing the counter.

Link: https://lkml.kernel.org/r/20241101191940.3211128-1-roman.gushchin@linux.dev
Fixes: 15bc01effe ("ucounts: Fix signal ucount refcounting")
Signed-off-by: Andrei Vagin <avagin@google.com>
Co-developed-by: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Tested-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Alexey Gladkov <legion@kernel.org>
Cc: Kees Cook <kees@kernel.org>
Cc: Andrei Vagin <avagin@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alexey Gladkov <legion@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:59 -08:00
Muhammad Usama Anjum
0268d45799 selftests: hugetlb_dio: check for initial conditions to skip in the start
The test should be skipped if initial conditions aren't fulfilled in the
start instead of failing and outputting non-compliant TAP logs.  This kind
of failure pollutes the results.  The initial conditions are:

- The test should only execute if /tmp file can be allocated.
- The test should only execute if huge pages are free.

Before:
TAP version 13
1..4
Bail out! Error opening file
: Read-only file system (30)
 # Planned tests != run tests (4 != 0)
 # Totals: pass:0 fail:0 xfail:0 xpass:0 skip:0 error:0

After:
TAP version 13
1..0 # SKIP Unable to allocate file: Read-only file system

Link: https://lkml.kernel.org/r/20241101141557.3159432-1-usama.anjum@collabora.com
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Fixes: 3a103b5315 ("selftest: mm: Test if hugepage does not get leaked during __bio_release_pages()")
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Donet Tom <donettom@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:59 -08:00
Maíra Canal
652e1a5146 mm: fix docs for the kernel parameter `thp_anon=`
If we add ``thp_anon=32,64K:always`` to the kernel command line, we
will see the following error:

[    0.000000] huge_memory: thp_anon=32,64K:always: error parsing string, ignoring setting

This happens because the correct format isn't ``thp_anon=<size>,<size>[KMG]:<state>```,
as [KMG] must follow each number to especify its unit. So, the correct
format is ``thp_anon=<size>[KMG],<size>[KMG]:<state>```.

Therefore, adjust the documentation to reflect the correct format of the
parameter ``thp_anon=``.

Link: https://lkml.kernel.org/r/20241101165719.1074234-3-mcanal@igalia.com
Fixes: dd4d30d1cd ("mm: override mTHP "enabled" defaults at kernel cmdline")
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Acked-by: Barry Song <baohua@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lance Yang <ioworker0@gmail.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:59 -08:00
SeongJae Park
4401e9d10a mm/damon/core: avoid overflow in damon_feed_loop_next_input()
damon_feed_loop_next_input() is inefficient and fragile to overflows. 
Specifically, 'score_goal_diff_bp' calculation can overflow when 'score'
is high.  The calculation is actually unnecessary at all because 'goal' is
a constant of value 10,000.  Calculation of 'compensation' is again
fragile to overflow.  Final calculation of return value for under-achiving
case is again fragile to overflow when the current score is
under-achieving the target.

Add two corner cases handling at the beginning of the function to make the
body easier to read, and rewrite the body of the function to avoid
overflows and the unnecessary bp value calcuation.

Link: https://lkml.kernel.org/r/20241031161203.47751-1-sj@kernel.org
Fixes: 9294a037c0 ("mm/damon/core: implement goal-oriented feedback-driven quota auto-tuning")
Signed-off-by: SeongJae Park <sj@kernel.org>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Closes: https://lore.kernel.org/944f3d5b-9177-48e7-8ec9-7f1331a3fea3@roeck-us.net
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: <stable@vger.kernel.org>	[6.8.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:59 -08:00
SeongJae Park
8e7bde615f mm/damon/core: handle zero schemes apply interval
DAMON's logics to determine if this is the time to apply damos schemes
assumes next_apply_sis is always set larger than current
passed_sample_intervals.  And therefore assume continuously incrementing
passed_sample_intervals will make it reaches to the next_apply_sis in
future.  The logic hence does apply the scheme and update next_apply_sis
only if passed_sample_intervals is same to next_apply_sis.

If Schemes apply interval is set as zero, however, next_apply_sis is set
same to current passed_sample_intervals, respectively.  And
passed_sample_intervals is incremented before doing the next_apply_sis
check.  Hence, next_apply_sis becomes larger than next_apply_sis, and the
logic says it is not the time to apply schemes and update next_apply_sis. 
In other words, DAMON stops applying schemes until passed_sample_intervals
overflows.

Based on the documents and the common sense, a reasonable behavior for
such inputs would be applying the schemes for every sampling interval. 
Handle the case by removing the assumption.

Link: https://lkml.kernel.org/r/20241031183757.49610-3-sj@kernel.org
Fixes: 42f994b714 ("mm/damon/core: implement scheme-specific apply interval")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>	[6.7.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:58 -08:00
SeongJae Park
3488af0970 mm/damon/core: handle zero {aggregation,ops_update} intervals
Patch series "mm/damon/core: fix handling of zero non-sampling intervals".

DAMON's internal intervals accounting logic is not correctly handling
non-sampling intervals of zero values for a wrong assumption.  This could
cause unexpected monitoring behavior, and even result in infinite hang of
DAMON sysfs interface user threads in case of zero aggregation interval. 
Fix those by updating the intervals accounting logic.  For details of the
root case and solutions, please refer to commit messages of fixes.


This patch (of 2):

DAMON's logics to determine if this is the time to do aggregation and ops
update assumes next_{aggregation,ops_update}_sis are always set larger
than current passed_sample_intervals.  And therefore it further assumes
continuously incrementing passed_sample_intervals every sampling interval
will make it reaches to the next_{aggregation,ops_update}_sis in future. 
The logic therefore make the action and update
next_{aggregation,ops_updaste}_sis only if passed_sample_intervals is same
to the counts, respectively.

If Aggregation interval or Ops update interval are zero, however,
next_aggregation_sis or next_ops_update_sis are set same to current
passed_sample_intervals, respectively.  And passed_sample_intervals is
incremented before doing the next_{aggregation,ops_update}_sis check. 
Hence, passed_sample_intervals becomes larger than
next_{aggregation,ops_update}_sis, and the logic says it is not the time
to do the action and update next_{aggregation,ops_update}_sis forever,
until an overflow happens.  In other words, DAMON stops doing aggregations
or ops updates effectively forever, and users cannot get monitoring
results.

Based on the documents and the common sense, a reasonable behavior for
such inputs is doing an aggregation and an ops update for every sampling
interval.  Handle the case by removing the assumption.

Note that this could incur particular real issue for DAMON sysfs interface
users, in case of zero Aggregation interval.  When user starts DAMON with
zero Aggregation interval and asks online DAMON parameter tuning via DAMON
sysfs interface, the request is handled by the aggregation callback. 
Until the callback finishes the work, the user who requested the online
tuning just waits.  Hence, the user will be stuck until the
passed_sample_intervals overflows.

Link: https://lkml.kernel.org/r/20241031183757.49610-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20241031183757.49610-2-sj@kernel.org
Fixes: 4472edf63d ("mm/damon/core: use number of passed access sampling as a timer")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>	[6.7.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:58 -08:00
Wei Yang
faa242b1d2 mm/mlock: set the correct prev on failure
After commit 94d7d92339 ("mm: abstract the vma_merge()/split_vma()
pattern for mprotect() et al."), if vma_modify_flags() return error, the
vma is set to an error code.  This will lead to an invalid prev be
returned.

Generally this shouldn't matter as the caller should treat an error as
indicating state is now invalidated, however unfortunately
apply_mlockall_flags() does not check for errors and assumes that
mlock_fixup() correctly maintains prev even if an error were to occur.

This patch fixes that assumption.

[lorenzo.stoakes@oracle.com: provide a better fix and rephrase the log]
Link: https://lkml.kernel.org/r/20241027123321.19511-1-richard.weiyang@gmail.com
Fixes: 94d7d92339 ("mm: abstract the vma_merge()/split_vma() pattern for mprotect() et al.")
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:58 -08:00
Masami Hiramatsu (Google)
cb6fcef8b4 objpool: fix to make percpu slot allocation more robust
Since gfp & GFP_ATOMIC == GFP_ATOMIC is true for GFP_KERNEL | GFP_HIGH, it
will use kmalloc if user specifies that combination.  Here the reason why
combining the __vmalloc_node() and kmalloc_node() is that the vmalloc does
not support all GFP flag, especially GFP_ATOMIC.  So we should check if
gfp & (GFP_ATOMIC | GFP_KERNEL) != GFP_ATOMIC for vmalloc first.  This
ensures caller can sleep.  And for the robustness, even if vmalloc fails,
it should retry with kmalloc to allocate it.

Link: https://lkml.kernel.org/r/173008598713.1262174.2959179484209897252.stgit@mhiramat.roam.corp.google.com
Fixes: aff1871bfc ("objpool: fix choosing allocation for percpu slots")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Closes: https://lore.kernel.org/all/CAHk-=whO+vSH+XVRio8byJU8idAWES0SPGVZ7KAVdc4qrV0VUA@mail.gmail.com/
Cc: Leo Yan <leo.yan@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Wu <wuqiang.matt@bytedance.com>
Cc: Mikel Rychliski <mikel@mikelr.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Viktor Malik <vmalik@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:58 -08:00
Yu Zhao
c928807f6f mm/page_alloc: keep track of free highatomic
OOM kills due to vastly overestimated free highatomic reserves were
observed:

  ... invoked oom-killer: gfp_mask=0x100cca(GFP_HIGHUSER_MOVABLE), order=0 ...
  Node 0 Normal free:1482936kB boost:0kB min:410416kB low:739404kB high:1068392kB reserved_highatomic:1073152KB ...
  Node 0 Normal: 1292*4kB (ME) 1920*8kB (E) 383*16kB (UE) 220*32kB (ME) 340*64kB (E) 2155*128kB (UE) 3243*256kB (UE) 615*512kB (U) 1*1024kB (M) 0*2048kB 0*4096kB = 1477408kB

The second line above shows that the OOM kill was due to the following
condition:

  free (1482936kB) - reserved_highatomic (1073152kB) = 409784KB < min (410416kB)

And the third line shows there were no free pages in any
MIGRATE_HIGHATOMIC pageblocks, which otherwise would show up as type 'H'. 
Therefore __zone_watermark_unusable_free() underestimated the usable free
memory by over 1GB, which resulted in the unnecessary OOM kill above.

The comments in __zone_watermark_unusable_free() warns about the potential
risk, i.e.,

  If the caller does not have rights to reserves below the min
  watermark then subtract the high-atomic reserves. This will
  over-estimate the size of the atomic reserve but it avoids a search.

However, it is possible to keep track of free pages in reserved highatomic
pageblocks with a new per-zone counter nr_free_highatomic protected by the
zone lock, to avoid a search when calculating the usable free memory.  And
the cost would be minimal, i.e., simple arithmetics in the highatomic
alloc/free/move paths.

Note that since nr_free_highatomic can be relatively small, using a
per-cpu counter might cause too much drift and defeat its purpose, in
addition to the extra memory overhead.

Dependson e0932b6c1f ("mm: page_alloc: consolidate free page accounting") - see [1]

[akpm@linux-foundation.org: s/if/else if/, per Johannes, stealth whitespace tweak]
Link: https://lkml.kernel.org/r/20241028182653.3420139-1-yuzhao@google.com
Link: https://lkml.kernel.org/r/0d0ddb33-fcdc-43e2-801f-0c1df2031afb@suse.cz [1]
Fixes: 0aaa29a56e ("mm, page_alloc: reserve pageblocks for high-order atomic allocations on demand")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Reported-by: Link Lin <linkl@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:14:58 -08:00
Lorenzo Stoakes
5de195060b mm: resolve faulty mmap_region() error path behaviour
The mmap_region() function is somewhat terrifying, with spaghetti-like
control flow and numerous means by which issues can arise and incomplete
state, memory leaks and other unpleasantness can occur.

A large amount of the complexity arises from trying to handle errors late
in the process of mapping a VMA, which forms the basis of recently
observed issues with resource leaks and observable inconsistent state.

Taking advantage of previous patches in this series we move a number of
checks earlier in the code, simplifying things by moving the core of the
logic into a static internal function __mmap_region().

Doing this allows us to perform a number of checks up front before we do
any real work, and allows us to unwind the writable unmap check
unconditionally as required and to perform a CONFIG_DEBUG_VM_MAPLE_TREE
validation unconditionally also.

We move a number of things here:

1. We preallocate memory for the iterator before we call the file-backed
   memory hook, allowing us to exit early and avoid having to perform
   complicated and error-prone close/free logic. We carefully free
   iterator state on both success and error paths.

2. The enclosing mmap_region() function handles the mapping_map_writable()
   logic early. Previously the logic had the mapping_map_writable() at the
   point of mapping a newly allocated file-backed VMA, and a matching
   mapping_unmap_writable() on success and error paths.

   We now do this unconditionally if this is a file-backed, shared writable
   mapping. If a driver changes the flags to eliminate VM_MAYWRITE, however
   doing so does not invalidate the seal check we just performed, and we in
   any case always decrement the counter in the wrapper.

   We perform a debug assert to ensure a driver does not attempt to do the
   opposite.

3. We also move arch_validate_flags() up into the mmap_region()
   function. This is only relevant on arm64 and sparc64, and the check is
   only meaningful for SPARC with ADI enabled. We explicitly add a warning
   for this arch if a driver invalidates this check, though the code ought
   eventually to be fixed to eliminate the need for this.

With all of these measures in place, we no longer need to explicitly close
the VMA on error paths, as we place all checks which might fail prior to a
call to any driver mmap hook.

This eliminates an entire class of errors, makes the code easier to reason
about and more robust.

Link: https://lkml.kernel.org/r/6e0becb36d2f5472053ac5d544c0edfe9b899e25.1730224667.git.lorenzo.stoakes@oracle.com
Fixes: deb0f65628 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reported-by: Jann Horn <jannh@google.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Mark Brown <broonie@kernel.org>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05 16:49:55 -08:00
Lorenzo Stoakes
5baf8b037d mm: refactor arch_calc_vm_flag_bits() and arm64 MTE handling
Currently MTE is permitted in two circumstances (desiring to use MTE
having been specified by the VM_MTE flag) - where MAP_ANONYMOUS is
specified, as checked by arch_calc_vm_flag_bits() and actualised by
setting the VM_MTE_ALLOWED flag, or if the file backing the mapping is
shmem, in which case we set VM_MTE_ALLOWED in shmem_mmap() when the mmap
hook is activated in mmap_region().

The function that checks that, if VM_MTE is set, VM_MTE_ALLOWED is also
set is the arm64 implementation of arch_validate_flags().

Unfortunately, we intend to refactor mmap_region() to perform this check
earlier, meaning that in the case of a shmem backing we will not have
invoked shmem_mmap() yet, causing the mapping to fail spuriously.

It is inappropriate to set this architecture-specific flag in general mm
code anyway, so a sensible resolution of this issue is to instead move the
check somewhere else.

We resolve this by setting VM_MTE_ALLOWED much earlier in do_mmap(), via
the arch_calc_vm_flag_bits() call.

This is an appropriate place to do this as we already check for the
MAP_ANONYMOUS case here, and the shmem file case is simply a variant of
the same idea - we permit RAM-backed memory.

This requires a modification to the arch_calc_vm_flag_bits() signature to
pass in a pointer to the struct file associated with the mapping, however
this is not too egregious as this is only used by two architectures anyway
- arm64 and parisc.

So this patch performs this adjustment and removes the unnecessary
assignment of VM_MTE_ALLOWED in shmem_mmap().

[akpm@linux-foundation.org: fix whitespace, per Catalin]
Link: https://lkml.kernel.org/r/ec251b20ba1964fb64cf1607d2ad80c47f3873df.1730224667.git.lorenzo.stoakes@oracle.com
Fixes: deb0f65628 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Jann Horn <jannh@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05 16:49:55 -08:00
Lorenzo Stoakes
0fb4a7ad27 mm: refactor map_deny_write_exec()
Refactor the map_deny_write_exec() to not unnecessarily require a VMA
parameter but rather to accept VMA flags parameters, which allows us to
use this function early in mmap_region() in a subsequent commit.

While we're here, we refactor the function to be more readable and add
some additional documentation.

Link: https://lkml.kernel.org/r/6be8bb59cd7c68006ebb006eb9d8dc27104b1f70.1730224667.git.lorenzo.stoakes@oracle.com
Fixes: deb0f65628 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reported-by: Jann Horn <jannh@google.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Jann Horn <jannh@google.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05 16:49:55 -08:00
Lorenzo Stoakes
4080ef1579 mm: unconditionally close VMAs on error
Incorrect invocation of VMA callbacks when the VMA is no longer in a
consistent state is bug prone and risky to perform.

With regards to the important vm_ops->close() callback We have gone to
great lengths to try to track whether or not we ought to close VMAs.

Rather than doing so and risking making a mistake somewhere, instead
unconditionally close and reset vma->vm_ops to an empty dummy operations
set with a NULL .close operator.

We introduce a new function to do so - vma_close() - and simplify existing
vms logic which tracked whether we needed to close or not.

This simplifies the logic, avoids incorrect double-calling of the .close()
callback and allows us to update error paths to simply call vma_close()
unconditionally - making VMA closure idempotent.

Link: https://lkml.kernel.org/r/28e89dda96f68c505cb6f8e9fc9b57c3e9f74b42.1730224667.git.lorenzo.stoakes@oracle.com
Fixes: deb0f65628 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reported-by: Jann Horn <jannh@google.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Jann Horn <jannh@google.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05 16:49:55 -08:00
Lorenzo Stoakes
3dd6ed34ce mm: avoid unsafe VMA hook invocation when error arises on mmap hook
Patch series "fix error handling in mmap_region() and refactor
(hotfixes)", v4.

mmap_region() is somewhat terrifying, with spaghetti-like control flow and
numerous means by which issues can arise and incomplete state, memory
leaks and other unpleasantness can occur.

A large amount of the complexity arises from trying to handle errors late
in the process of mapping a VMA, which forms the basis of recently
observed issues with resource leaks and observable inconsistent state.

This series goes to great lengths to simplify how mmap_region() works and
to avoid unwinding errors late on in the process of setting up the VMA for
the new mapping, and equally avoids such operations occurring while the
VMA is in an inconsistent state.

The patches in this series comprise the minimal changes required to
resolve existing issues in mmap_region() error handling, in order that
they can be hotfixed and backported.  There is additionally a follow up
series which goes further, separated out from the v1 series and sent and
updated separately.


This patch (of 5):

After an attempted mmap() fails, we are no longer in a situation where we
can safely interact with VMA hooks.  This is currently not enforced,
meaning that we need complicated handling to ensure we do not incorrectly
call these hooks.

We can avoid the whole issue by treating the VMA as suspect the moment
that the file->f_ops->mmap() function reports an error by replacing
whatever VMA operations were installed with a dummy empty set of VMA
operations.

We do so through a new helper function internal to mm - mmap_file() -
which is both more logically named than the existing call_mmap() function
and correctly isolates handling of the vm_op reassignment to mm.

All the existing invocations of call_mmap() outside of mm are ultimately
nested within the call_mmap() from mm, which we now replace.

It is therefore safe to leave call_mmap() in place as a convenience
function (and to avoid churn).  The invokers are:

     ovl_file_operations -> mmap -> ovl_mmap() -> backing_file_mmap()
    coda_file_operations -> mmap -> coda_file_mmap()
     shm_file_operations -> shm_mmap()
shm_file_operations_huge -> shm_mmap()
            dma_buf_fops -> dma_buf_mmap_internal -> i915_dmabuf_ops
	                    -> i915_gem_dmabuf_mmap()

None of these callers interact with vm_ops or mappings in a problematic
way on error, quickly exiting out.

Link: https://lkml.kernel.org/r/cover.1730224667.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/d41fd763496fd0048a962f3fd9407dc72dd4fd86.1730224667.git.lorenzo.stoakes@oracle.com
Fixes: deb0f65628 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reported-by: Jann Horn <jannh@google.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Jann Horn <jannh@google.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05 16:49:54 -08:00
Hugh Dickins
f8f931bba0 mm/thp: fix deferred split unqueue naming and locking
Recent changes are putting more pressure on THP deferred split queues:
under load revealing long-standing races, causing list_del corruptions,
"Bad page state"s and worse (I keep BUGs in both of those, so usually
don't get to see how badly they end up without).  The relevant recent
changes being 6.8's mTHP, 6.10's mTHP swapout, and 6.12's mTHP swapin,
improved swap allocation, and underused THP splitting.

Before fixing locking: rename misleading folio_undo_large_rmappable(),
which does not undo large_rmappable, to folio_unqueue_deferred_split(),
which is what it does.  But that and its out-of-line __callee are mm
internals of very limited usability: add comment and WARN_ON_ONCEs to
check usage; and return a bool to say if a deferred split was unqueued,
which can then be used in WARN_ON_ONCEs around safety checks (sparing
callers the arcane conditionals in __folio_unqueue_deferred_split()).

Just omit the folio_unqueue_deferred_split() from free_unref_folios(), all
of whose callers now call it beforehand (and if any forget then bad_page()
will tell) - except for its caller put_pages_list(), which itself no
longer has any callers (and will be deleted separately).

Swapout: mem_cgroup_swapout() has been resetting folio->memcg_data 0
without checking and unqueueing a THP folio from deferred split list;
which is unfortunate, since the split_queue_lock depends on the memcg
(when memcg is enabled); so swapout has been unqueueing such THPs later,
when freeing the folio, using the pgdat's lock instead: potentially
corrupting the memcg's list.  __remove_mapping() has frozen refcount to 0
here, so no problem with calling folio_unqueue_deferred_split() before
resetting memcg_data.

That goes back to 5.4 commit 87eaceb3fa ("mm: thp: make deferred split
shrinker memcg aware"): which included a check on swapcache before adding
to deferred queue, but no check on deferred queue before adding THP to
swapcache.  That worked fine with the usual sequence of events in reclaim
(though there were a couple of rare ways in which a THP on deferred queue
could have been swapped out), but 6.12 commit dafff3f4c8 ("mm: split
underused THPs") avoids splitting underused THPs in reclaim, which makes
swapcache THPs on deferred queue commonplace.

Keep the check on swapcache before adding to deferred queue?  Yes: it is
no longer essential, but preserves the existing behaviour, and is likely
to be a worthwhile optimization (vmstat showed much more traffic on the
queue under swapping load if the check was removed); update its comment.

Memcg-v1 move (deprecated): mem_cgroup_move_account() has been changing
folio->memcg_data without checking and unqueueing a THP folio from the
deferred list, sometimes corrupting "from" memcg's list, like swapout. 
Refcount is non-zero here, so folio_unqueue_deferred_split() can only be
used in a WARN_ON_ONCE to validate the fix, which must be done earlier:
mem_cgroup_move_charge_pte_range() first try to split the THP (splitting
of course unqueues), or skip it if that fails.  Not ideal, but moving
charge has been requested, and khugepaged should repair the THP later:
nobody wants new custom unqueueing code just for this deprecated case.

The 87eaceb3fa commit did have the code to move from one deferred list
to another (but was not conscious of its unsafety while refcount non-0);
but that was removed by 5.6 commit fac0516b55 ("mm: thp: don't need care
deferred split queue in memcg charge move path"), which argued that the
existence of a PMD mapping guarantees that the THP cannot be on a deferred
list.  As above, false in rare cases, and now commonly false.

Backport to 6.11 should be straightforward.  Earlier backports must take
care that other _deferred_list fixes and dependencies are included.  There
is not a strong case for backports, but they can fix cornercases.

Link: https://lkml.kernel.org/r/8dc111ae-f6db-2da7-b25c-7a20b1effe3b@google.com
Fixes: 87eaceb3fa ("mm: thp: make deferred split shrinker memcg aware")
Fixes: dafff3f4c8 ("mm: split underused THPs")
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05 16:49:54 -08:00
Hugh Dickins
e66f3185fa mm/thp: fix deferred split queue not partially_mapped
Recent changes are putting more pressure on THP deferred split queues:
under load revealing long-standing races, causing list_del corruptions,
"Bad page state"s and worse (I keep BUGs in both of those, so usually
don't get to see how badly they end up without).  The relevant recent
changes being 6.8's mTHP, 6.10's mTHP swapout, and 6.12's mTHP swapin,
improved swap allocation, and underused THP splitting.

The new unlocked list_del_init() in deferred_split_scan() is buggy.  I
gave bad advice, it looks plausible since that's a local on-stack list,
but the fact is that it can race with a third party freeing or migrating
the preceding folio (properly unqueueing it with refcount 0 while holding
split_queue_lock), thereby corrupting the list linkage.

The obvious answer would be to take split_queue_lock there: but it has a
long history of contention, so I'm reluctant to add to that.  Instead,
make sure that there is always one safe (raised refcount) folio before, by
delaying its folio_put().  (And of course I was wrong to suggest updating
split_queue_len without the lock: leave that until the splice.)

And remove two over-eager partially_mapped checks, restoring those tests
to how they were before: if uncharge_folio() or free_tail_page_prepare()
finds _deferred_list non-empty, it's in trouble whether or not that folio
is partially_mapped (and the flag was already cleared in the latter case).

Link: https://lkml.kernel.org/r/81e34a8b-113a-0701-740e-2135c97eb1d7@google.com
Fixes: dafff3f4c8 ("mm: split underused THPs")
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Usama Arif <usamaarif642@gmail.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05 16:49:54 -08:00
Linus Torvalds
59b723cd2a Linux 6.12-rc6 2024-11-03 14:05:52 -10:00
Linus Torvalds
a8cc743272 17 hotfixes. 9 are cc:stable. 13 are MM and 4 are non-MM.
The usual collection of singletons - please see the changelogs.
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Merge tag 'mm-hotfixes-stable-2024-11-03-10-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "17 hotfixes.  9 are cc:stable.  13 are MM and 4 are non-MM.

  The usual collection of singletons - please see the changelogs"

* tag 'mm-hotfixes-stable-2024-11-03-10-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  mm: multi-gen LRU: use {ptep,pmdp}_clear_young_notify()
  mm: multi-gen LRU: remove MM_LEAF_OLD and MM_NONLEAF_TOTAL stats
  mm, mmap: limit THP alignment of anonymous mappings to PMD-aligned sizes
  mm: shrinker: avoid memleak in alloc_shrinker_info
  .mailmap: update e-mail address for Eugen Hristev
  vmscan,migrate: fix page count imbalance on node stats when demoting pages
  mailmap: update Jarkko's email addresses
  mm: allow set/clear page_type again
  nilfs2: fix potential deadlock with newly created symlinks
  Squashfs: fix variable overflow in squashfs_readpage_block
  kasan: remove vmalloc_percpu test
  tools/mm: -Werror fixes in page-types/slabinfo
  mm, swap: avoid over reclaim of full clusters
  mm: fix PSWPIN counter for large folios swap-in
  mm: avoid VM_BUG_ON when try to map an anon large folio to zero page.
  mm/codetag: fix null pointer check logic for ref and tag
  mm/gup: stop leaking pinned pages in low memory conditions
2024-11-03 10:25:05 -10:00
Linus Torvalds
d5aaa0bc6d phy fixes for 6.12
- Bunch of Qualcomm QMP driver fixes for null deref on suspend, bogus
    supplies fix and reset entries fix
  - BCM usb driver init array fix
  - cadence array offset fix
  - starfive link configuration fix
  - config dependency fix for rockchip driver
  - freescale reset signal fix before pll lock
  - tegra driver fix for error pointer check
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Merge tag 'phy-fixes-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/phy/linux-phy

Pull phy fixes from Vinod Koul:

 - Qualcomm QMP driver fixes for null deref on suspend, bogus supplies
   fix and reset entries fix

 - BCM usb driver init array fix

 - cadence array offset fix

 - starfive link configuration fix

 - config dependency fix for rockchip driver

 - freescale reset signal fix before pll lock

 - tegra driver fix for error pointer check

* tag 'phy-fixes-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/phy/linux-phy:
  phy: tegra: xusb: Add error pointer check in xusb.c
  dt-bindings: phy: qcom,sc8280xp-qmp-pcie-phy: Fix X1E80100 resets entries
  phy: freescale: imx8m-pcie: Do CMN_RST just before PHY PLL lock check
  phy: phy-rockchip-samsung-hdptx: Depend on CONFIG_COMMON_CLK
  phy: ti: phy-j721e-wiz: fix usxgmii configuration
  phy: starfive: jh7110-usb: Fix link configuration to controller
  phy: qcom: qmp-pcie: drop bogus x1e80100 qref supplies
  phy: qcom: qmp-combo: move driver data initialisation earlier
  phy: qcom: qmp-usbc: fix NULL-deref on runtime suspend
  phy: qcom: qmp-usb-legacy: fix NULL-deref on runtime suspend
  phy: qcom: qmp-usb: fix NULL-deref on runtime suspend
  dt-bindings: phy: qcom,sc8280xp-qmp-pcie-phy: add missing x1e80100 pipediv2 clocks
  phy: usb: disable COMMONONN for dual mode
  phy: cadence: Sierra: Fix offset of DEQ open eye algorithm control register
  phy: usb: Fix missing elements in BCM4908 USB init array
2024-11-03 10:19:34 -10:00
Linus Torvalds
e8529dcb12 dmaengine fixes for v6.12
Driver fixes for:
  - TI driver fix to set EOP for cyclic BCDMA transfers
  - sh rz-dmac driver fix for handling config with zero address
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Merge tag 'dmaengine-fix-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine

Pull dmaengine fixes from Vinod Koul:

 - TI driver fix to set EOP for cyclic BCDMA transfers

 - sh rz-dmac driver fix for handling config with zero address

* tag 'dmaengine-fix-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine:
  dmaengine: ti: k3-udma: Set EOP for all TRs in cyclic BCDMA transfer
  dmaengine: sh: rz-dmac: handle configs where one address is zero
2024-11-03 10:15:50 -10:00
Linus Torvalds
886b7e80ab Driver core revert fix for 6.12-rc6
Here is a single driver core revert for 6.12-rc6.  It reverts a change
 that came in -rc1 that was supposed to resolve a reported problem, but
 caused another one, so revert it for now so that we can get this all
 worked out properly in 6.13.
 
 The revert has been in linux-next all week with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core revert from Greg KH:
 "Here is a single driver core revert for 6.12-rc6. It reverts a change
  that came in -rc1 that was supposed to resolve a reported problem, but
  caused another one, so revert it for now so that we can get this all
  worked out properly in 6.13.

  The revert has been in linux-next all week with no reported issues"

* tag 'driver-core-6.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  Revert "driver core: Fix uevent_show() vs driver detach race"
2024-11-03 08:51:53 -10:00
Linus Torvalds
be5bfa1378 USB / Thunderbolt fixes for 6.12-rc6
Here are some small USB and Thunderbolt driver fixes for 6.12-rc6 that
 have been sitting in my tree this week.  Included in here are the
 following:
   - thunderbolt driver fixes for reported issues
   - USB typec driver fixes
   - xhci driver fixes for reported problems
   - dwc2 driver revert for a broken change
   - usb phy driver fix
   - usbip tool fix
 
 All of these have been in linux-next this week with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-6.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB / Thunderbolt fixes from Greg KH:
 "Here are some small USB and Thunderbolt driver fixes for 6.12-rc6 that
  have been sitting in my tree this week. Included in here are the
  following:

   - thunderbolt driver fixes for reported issues

   - USB typec driver fixes

   - xhci driver fixes for reported problems

   - dwc2 driver revert for a broken change

   - usb phy driver fix

   - usbip tool fix

  All of these have been in linux-next this week with no reported
  issues"

* tag 'usb-6.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: typec: tcpm: restrict SNK_WAIT_CAPABILITIES_TIMEOUT transitions to non self-powered devices
  usb: phy: Fix API devm_usb_put_phy() can not release the phy
  usb: typec: use cleanup facility for 'altmodes_node'
  usb: typec: fix unreleased fwnode_handle in typec_port_register_altmodes()
  usb: typec: qcom-pmic-typec: fix missing fwnode removal in error path
  usb: typec: qcom-pmic-typec: use fwnode_handle_put() to release fwnodes
  usb: acpi: fix boot hang due to early incorrect 'tunneled' USB3 device links
  Revert "usb: dwc2: Skip clock gating on Broadcom SoCs"
  xhci: Fix Link TRB DMA in command ring stopped completion event
  xhci: Use pm_runtime_get to prevent RPM on unsupported systems
  usbip: tools: Fix detach_port() invalid port error path
  thunderbolt: Honor TMU requirements in the domain when setting TMU mode
  thunderbolt: Fix KASAN reported stack out-of-bounds read in tb_retimer_scan()
2024-11-03 08:48:11 -10:00
Yu Zhao
1d4832becd mm: multi-gen LRU: use {ptep,pmdp}_clear_young_notify()
When the MM_WALK capability is enabled, memory that is mostly accessed by
a VM appears younger than it really is, therefore this memory will be less
likely to be evicted.  Therefore, the presence of a running VM can
significantly increase swap-outs for non-VM memory, regressing the
performance for the rest of the system.

Fix this regression by always calling {ptep,pmdp}_clear_young_notify()
whenever we clear the young bits on PMDs/PTEs.

[jthoughton@google.com: fix link-time error]
Link: https://lkml.kernel.org/r/20241019012940.3656292-3-jthoughton@google.com
Fixes: bd74fdaea1 ("mm: multi-gen LRU: support page table walks")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: James Houghton <jthoughton@google.com>
Reported-by: David Stevens <stevensd@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Matlack <dmatlack@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Wei Xu <weixugc@google.com>
Cc: <stable@vger.kernel.org>
Cc: kernel test robot <lkp@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-03 10:47:03 -08:00
Yu Zhao
ddd6d8e975 mm: multi-gen LRU: remove MM_LEAF_OLD and MM_NONLEAF_TOTAL stats
Patch series "mm: multi-gen LRU: Have secondary MMUs participate in
MM_WALK".

Today, the MM_WALK capability causes MGLRU to clear the young bit from
PMDs and PTEs during the page table walk before eviction, but MGLRU does
not call the clear_young() MMU notifier in this case.  By not calling this
notifier, the MM walk takes less time/CPU, but it causes pages that are
accessed mostly through KVM / secondary MMUs to appear younger than they
should be.

We do call the clear_young() notifier today, but only when attempting to
evict the page, so we end up clearing young/accessed information less
frequently for secondary MMUs than for mm PTEs, and therefore they appear
younger and are less likely to be evicted.  Therefore, memory that is
*not* being accessed mostly by KVM will be evicted *more* frequently,
worsening performance.

ChromeOS observed a tab-open latency regression when enabling MGLRU with a
setup that involved running a VM:

		Tab-open latency histogram (ms)
Version		p50	mean	p95	p99	max
base		1315	1198	2347	3454	10319
mglru		2559	1311	7399	12060	43758
fix		1119	926	2470	4211	6947

This series replaces the final non-selftest patchs from this series[1],
which introduced a similar change (and a new MMU notifier) with KVM
optimizations.  I'll send a separate series (to Sean and Paolo) for the
KVM optimizations.

This series also makes proactive reclaim with MGLRU possible for KVM
memory.  I have verified that this functions correctly with the selftest
from [1], but given that that test is a KVM selftest, I'll send it with
the rest of the KVM optimizations later.  Andrew, let me know if you'd
like to take the test now anyway.

[1]: https://lore.kernel.org/linux-mm/20240926013506.860253-18-jthoughton@google.com/


This patch (of 2):

The removed stats, MM_LEAF_OLD and MM_NONLEAF_TOTAL, are not very helpful
and become more complicated to properly compute when adding
test/clear_young() notifiers in MGLRU's mm walk.

Link: https://lkml.kernel.org/r/20241019012940.3656292-1-jthoughton@google.com
Link: https://lkml.kernel.org/r/20241019012940.3656292-2-jthoughton@google.com
Fixes: bd74fdaea1 ("mm: multi-gen LRU: support page table walks")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: James Houghton <jthoughton@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Matlack <dmatlack@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: David Stevens <stevensd@google.com>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Wei Xu <weixugc@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-03 10:47:02 -08:00
Linus Torvalds
32cfb3c48e Char/Misc/IIO driver fixes for 6.12-rc6
Here are some small char/misc/iio fixes for 6.12-rc6 that resolves some
 reported issues.  Included in here are the following:
   - small IIO driver fixes for many reported issues
   - mei driver fix for a suddenly much reported issue for an "old"
     issue.
   - MAINTAINERS update for a developer who has moved companies and
     forgot to update their old entry.
 
 All of these have been in linux-next this week with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-6.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull misc driver fixes from Greg KH:
 "Here are some small char/misc/iio fixes for 6.12-rc6 that resolve
  some reported issues. Included in here are the following:

   - small IIO driver fixes for many reported issues

   - mei driver fix for a suddenly much reported issue for an "old"
     issue.

   - MAINTAINERS update for a developer who has moved companies and
     forgot to update their old entry.

  All of these have been in linux-next this week with no reported
  issues"

* tag 'char-misc-6.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  mei: use kvmalloc for read buffer
  MAINTAINERS: add netup_unidvb maintainer
  iio: dac: Kconfig: Fix build error for ltc2664
  iio: adc: ad7124: fix division by zero in ad7124_set_channel_odr()
  staging: iio: frequency: ad9832: fix division by zero in ad9832_calc_freqreg()
  docs: iio: ad7380: fix supply for ad7380-4
  iio: adc: ad7380: fix supplies for ad7380-4
  iio: adc: ad7380: add missing supplies
  iio: adc: ad7380: use devm_regulator_get_enable_read_voltage()
  dt-bindings: iio: adc: ad7380: fix ad7380-4 reference supply
  iio: light: veml6030: fix microlux value calculation
  iio: gts-helper: Fix memory leaks for the error path of iio_gts_build_avail_scale_table()
  iio: gts-helper: Fix memory leaks in iio_gts_build_avail_scale_table()
2024-11-03 08:45:03 -10:00
Linus Torvalds
295ba6501d Input updates for v6.12-rc5
- a fix for regression in input core introduced in 6.11 preventing
   re-registering input handlers
 
 - a fix for adp5588-keys driver tyring to disable interrupt 0 at suspend
   when devices is used without interrupt
 
 - a fix for edt-ft5x06 to stop leaking regmap structure when probing
   fails and to make sure it is not released too early on removal.
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Merge tag 'input-for-v6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

Pull input fixes from Dmitry Torokhov:

 - a fix for regression in input core introduced in 6.11 preventing
   re-registering input handlers

 - a fix for adp5588-keys driver tyring to disable interrupt 0 at
   suspend when devices is used without interrupt

 - a fix for edt-ft5x06 to stop leaking regmap structure when probing
   fails and to make sure it is not released too early on removal.

* tag 'input-for-v6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: fix regression when re-registering input handlers
  Input: adp5588-keys - do not try to disable interrupt 0
  Input: edt-ft5x06 - fix regmap leak when probe fails
2024-11-03 08:35:29 -10:00
Linus Torvalds
a33ab3f94f Kbuild fixes for v6.12 (2nd)
- Fix a memory leak in modpost
 
  - Resolve build issues when cross-compiling RPM and Debian packages
 
  - Fix another regression in Kconfig
 
  - Fix incorrect MODULE_ALIAS() output in modpost
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Merge tag 'kbuild-fixes-v6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Fix a memory leak in modpost

 - Resolve build issues when cross-compiling RPM and Debian packages

 - Fix another regression in Kconfig

 - Fix incorrect MODULE_ALIAS() output in modpost

* tag 'kbuild-fixes-v6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  modpost: fix input MODULE_DEVICE_TABLE() built for 64-bit on 32-bit host
  modpost: fix acpi MODULE_DEVICE_TABLE built with mismatched endianness
  kconfig: show sub-menu entries even if the prompt is hidden
  kbuild: deb-pkg: add pkg.linux-upstream.nokerneldbg build profile
  kbuild: deb-pkg: add pkg.linux-upstream.nokernelheaders build profile
  kbuild: rpm-pkg: disable kernel-devel package when cross-compiling
  sumversion: Fix a memory leak in get_src_version()
2024-11-03 08:29:02 -10:00
Linus Torvalds
b9021de3ec A trivial compile test fix for x86
When CONFIG_AMD_NB is not set a COMPILE_TEST of an AMD specific driver
   fails due to a missing inline stub. Add the stub to cure it.
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Merge tag 'x86-urgent-2024-11-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fix from Thomas Gleixner:
 "A trivial compile test fix for x86:

  When CONFIG_AMD_NB is not set a COMPILE_TEST of an AMD specific driver
  fails due to a missing inline stub. Add the stub to cure it"

* tag 'x86-urgent-2024-11-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/amd_nb: Fix compile-testing without CONFIG_AMD_NB
2024-11-03 08:26:00 -10:00
Linus Torvalds
b019b4a670 A single fix for posix CPU timers
When a thread is cloned, the posix CPU timers are not inherited.
 
   If the parent has a CPU timer armed the corresponding tick dependency in
   the tasks tick_dep_mask is set and copied to the new thread, which means
   the new thread and all decendants will prevent the system to go into full
   NOHZ operation.
 
   Clear the tick dependency mask in copy_process() to fix this.
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Merge tag 'timers-urgent-2024-11-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fix from Thomas Gleixner:
 "A single fix for posix CPU timers.

  When a thread is cloned, the posix CPU timers are not inherited.

  If the parent has a CPU timer armed the corresponding tick dependency
  in the tasks tick_dep_mask is set and copied to the new thread, which
  means the new thread and all decendants will prevent the system to go
  into full NOHZ operation.

  Clear the tick dependency mask in copy_process() to fix this"

* tag 'timers-urgent-2024-11-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  posix-cpu-timers: Clear TICK_DEP_BIT_POSIX_TIMER on clone
2024-11-03 08:22:21 -10:00
Linus Torvalds
33e83ffe4c A few scheduler fixes:
- Plug a race between pick_next_task_fair() and try_to_wake_up() where
    both try to write to the same task, even though both paths hold a
    runqueue lock, but obviously from different runqueues.
 
    The problem is that the store to task::on_rq in __block_task() is
    visible to try_to_wake_up() which assumes that the task is not queued.
    Both sides then operate on the same task.
 
    Cure it by rearranging __block_task() so the the store to task::on_rq is
    the last operation on the task.
 
  - Prevent a potential NULL pointer dereference in task_numa_work()
 
    task_numa_work() iterates the VMAs of a process. A concurrent unmap of
    the address space can result in a NULL pointer return from vma_next()
    which is unchecked.
 
    Add the missing NULL pointer check to prevent this.
 
  - Operate on the correct scheduler policy in task_should_scx()
 
    task_should_scx() returns true when a task should be handled by sched
    EXT. It checks the tasks scheduling policy.
 
    This fails when the check is done before a policy has been set.
 
    Cure it by handing the policy into task_should_scx() so it operates
    on the requested value.
 
  - Add the missing handling of sched EXT in the delayed dequeue
    mechanism. This was simply forgotten.
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Merge tag 'sched-urgent-2024-11-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler fixes from Thomas Gleixner:

 - Plug a race between pick_next_task_fair() and try_to_wake_up() where
   both try to write to the same task, even though both paths hold a
   runqueue lock, but obviously from different runqueues.

   The problem is that the store to task::on_rq in __block_task() is
   visible to try_to_wake_up() which assumes that the task is not
   queued. Both sides then operate on the same task.

   Cure it by rearranging __block_task() so the the store to task::on_rq
   is the last operation on the task.

 - Prevent a potential NULL pointer dereference in task_numa_work()

   task_numa_work() iterates the VMAs of a process. A concurrent unmap
   of the address space can result in a NULL pointer return from
   vma_next() which is unchecked.

   Add the missing NULL pointer check to prevent this.

 - Operate on the correct scheduler policy in task_should_scx()

   task_should_scx() returns true when a task should be handled by sched
   EXT. It checks the tasks scheduling policy.

   This fails when the check is done before a policy has been set.

   Cure it by handing the policy into task_should_scx() so it operates
   on the requested value.

 - Add the missing handling of sched EXT in the delayed dequeue
   mechanism. This was simply forgotten.

* tag 'sched-urgent-2024-11-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/ext: Fix scx vs sched_delayed
  sched: Pass correct scheduling policy to __setscheduler_class
  sched/numa: Fix the potential null pointer dereference in task_numa_work()
  sched: Fix pick_next_task_fair() vs try_to_wake_up() race
2024-11-03 08:18:28 -10:00
Linus Torvalds
68f05b251b A single fix for perf:
perf_event_clear_cpumask() uses list_for_each_entry_rcu() without being
   in a RCU read side critical section, which triggers a "suspicious RCU
   usage" warning.
 
   It turns out that the list walk does not be RCU protected because the
   write side lock is held in this contxt.
 
   Change it to a regular list walk.
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Merge tag 'perf-urgent-2024-11-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fix from Thomas Gleixner:
 "perf_event_clear_cpumask() uses list_for_each_entry_rcu() without
  being in a RCU read side critical section, which triggers a
  'suspicious RCU usage' warning.

  It turns out that the list walk does not be RCU protected because the
  write side lock is held in this context.

  Change it to a regular list walk"

* tag 'perf-urgent-2024-11-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix missing RCU reader protection in perf_event_clear_cpumask()
2024-11-03 08:13:52 -10:00
Linus Torvalds
8f0b844adc Two fixes for the interrupt subsystem:
- Fix an off-by-one error in the failure path of msi_domain_alloc(),
     which causes the cleanup loop to terminate early and leaking the first
     allocated interrupt.
 
   - Handle a corner case in GIC-V4 versus a lazily mapped Virtual
     Processing Element (VPE). If the VPE has not been mapped because the
     guest has not yet emitted a mapping command, then the set_affinity()
     callback returns an error code, which causes the vCPU management to fail.
 
     Return success in this case without touching the hardware. This will be
     done later when the guest issues the mapping command.
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Merge tag 'irq-urgent-2024-11-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fixes from Thomas Gleixner:

 - Fix an off-by-one error in the failure path of msi_domain_alloc(),
   which causes the cleanup loop to terminate early and leaking the
   first allocated interrupt.

 - Handle a corner case in GIC-V4 versus a lazily mapped Virtual
   Processing Element (VPE). If the VPE has not been mapped because the
   guest has not yet emitted a mapping command, then the set_affinity()
   callback returns an error code, which causes the vCPU management to
   fail.

   Return success in this case without touching the hardware. This will
   be done later when the guest issues the mapping command.

* tag 'irq-urgent-2024-11-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-v4: Correctly deal with set_affinity on lazily-mapped VPEs
  genirq/msi: Fix off-by-one error in msi_domain_alloc()
2024-11-03 08:09:25 -10:00
Masahiro Yamada
77dc55a978 modpost: fix input MODULE_DEVICE_TABLE() built for 64-bit on 32-bit host
When building a 64-bit kernel on a 32-bit build host, incorrect
input MODULE_ALIAS() entries may be generated.

For example, when compiling a 64-bit kernel with CONFIG_INPUT_MOUSEDEV=m
on a 64-bit build machine, you will get the correct output:

  $ grep MODULE_ALIAS drivers/input/mousedev.mod.c
  MODULE_ALIAS("input:b*v*p*e*-e*1,*2,*k*110,*r*0,*1,*a*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*2,*k*r*8,*a*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*3,*k*14A,*r*a*0,*1,*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*3,*k*145,*r*a*0,*1,*18,*1C,*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*3,*k*110,*r*a*0,*1,*m*l*s*f*w*");

However, building the same kernel on a 32-bit machine results in
incorrect output:

  $ grep MODULE_ALIAS drivers/input/mousedev.mod.c
  MODULE_ALIAS("input:b*v*p*e*-e*1,*2,*k*110,*130,*r*0,*1,*a*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*2,*k*r*8,*a*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*3,*k*14A,*16A,*r*a*0,*1,*20,*21,*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*3,*k*145,*165,*r*a*0,*1,*18,*1C,*20,*21,*38,*3C,*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*3,*k*110,*130,*r*a*0,*1,*20,*21,*m*l*s*f*w*");

A similar issue occurs with CONFIG_INPUT_JOYDEV=m. On a 64-bit build
machine, the output is:

  $ grep MODULE_ALIAS drivers/input/joydev.mod.c
  MODULE_ALIAS("input:b*v*p*e*-e*3,*k*r*a*0,*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*3,*k*r*a*2,*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*3,*k*r*a*8,*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*3,*k*r*a*6,*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*k*120,*r*a*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*k*130,*r*a*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*k*2C0,*r*a*m*l*s*f*w*");

However, on a 32-bit machine, the output is incorrect:

  $ grep MODULE_ALIAS drivers/input/joydev.mod.c
  MODULE_ALIAS("input:b*v*p*e*-e*3,*k*r*a*0,*20,*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*3,*k*r*a*2,*22,*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*3,*k*r*a*8,*28,*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*3,*k*r*a*6,*26,*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*k*11F,*13F,*r*a*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*k*11F,*13F,*r*a*m*l*s*f*w*");
  MODULE_ALIAS("input:b*v*p*e*-e*1,*k*2C0,*2E0,*r*a*m*l*s*f*w*");

When building a 64-bit kernel, BITS_PER_LONG is defined as 64. However,
on a 32-bit build machine, the constant 1L is a signed 32-bit value.
Left-shifting it beyond 32 bits causes wraparound, and shifting by 31
or 63 bits makes it a negative value.

The fix in commit e0e9263271 ("[PATCH] PATCH: 1 line 2.6.18 bugfix:
modpost-64bit-fix.patch") is incorrect; it only addresses cases where
a 64-bit kernel is built on a 64-bit build machine, overlooking cases
on a 32-bit build machine.

Using 1ULL ensures a 64-bit width on both 32-bit and 64-bit machines,
avoiding the wraparound issue.

Fixes: e0e9263271 ("[PATCH] PATCH: 1 line 2.6.18 bugfix: modpost-64bit-fix.patch")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-11-03 23:58:56 +09:00