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| Kernel | Title | Rank 🛈 | Repro | Cause bisect | Fix bisect | Count | Last | Reported | Patched | Status |
|---|---|---|---|---|---|---|---|---|---|---|
| upstream | possible deadlock in page_cache_ra_unbounded mm fs | 4 | C | error | done | 163 | 230d | 990d | 28/29 | fixed on 2025/03/05 08:48 |
| linux-6.1 | possible deadlock in page_cache_ra_unbounded | 4 | 4 | 52d | 52d | 0/3 | upstream: reported on 2025/07/16 14:50 | |||
| upstream | possible deadlock in page_cache_ra_unbounded (2) fs mm | 4 | 3 | 67d | 142d | 0/29 | moderation: reported on 2025/04/17 16:05 |
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz-executor/9812 is trying to acquire lock:
ffff888148cb8940 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:859 [inline]
ffff888148cb8940 (mapping.invalidate_lock#2){++++}-{3:3}, at: page_cache_ra_unbounded+0xdc/0x770 mm/readahead.c:225
but task is already holding lock:
ffff8880595a2210 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: iterate_dir+0xcb/0x580 fs/readdir.c:99
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #4 (&type->i_mutex_dir_key#3){++++}-{3:3}:
down_write+0x97/0x1f0 kernel/locking/rwsem.c:1573
inode_lock include/linux/fs.h:804 [inline]
ext4_process_orphan+0x187/0x300 fs/ext4/orphan.c:337
ext4_orphan_cleanup+0xbd4/0x1400 fs/ext4/orphan.c:474
__ext4_fill_super fs/ext4/super.c:5608 [inline]
ext4_fill_super+0x5de7/0x66c0 fs/ext4/super.c:5731
get_tree_bdev+0x3e4/0x510 fs/super.c:1591
vfs_get_tree+0x8c/0x280 fs/super.c:1764
do_new_mount+0x24b/0xa40 fs/namespace.c:3377
do_mount fs/namespace.c:3717 [inline]
__do_sys_mount fs/namespace.c:3926 [inline]
__se_sys_mount+0x2da/0x3c0 fs/namespace.c:3903
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #3 (&type->s_umount_key#31){++++}-{3:3}:
down_read+0x46/0x2e0 kernel/locking/rwsem.c:1520
__super_lock fs/super.c:58 [inline]
super_lock+0x167/0x360 fs/super.c:117
super_lock_shared fs/super.c:146 [inline]
super_lock_shared_active fs/super.c:1442 [inline]
fs_bdev_sync+0xa4/0x170 fs/super.c:1477
blkdev_flushbuf block/ioctl.c:375 [inline]
blkdev_common_ioctl+0x880/0x23d0 block/ioctl.c:505
blkdev_ioctl+0x4eb/0x6f0 block/ioctl.c:627
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #2 (&bdev->bd_holder_lock){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747
bd_finish_claiming+0x22f/0x3f0 block/bdev.c:568
blkdev_get_by_dev+0x45c/0x600 block/bdev.c:801
bdev_open_by_dev+0x77/0x100 block/bdev.c:842
setup_bdev_super+0x59/0x660 fs/super.c:1496
mount_bdev+0x1dd/0x2d0 fs/super.c:1640
legacy_get_tree+0xea/0x180 fs/fs_context.c:662
vfs_get_tree+0x8c/0x280 fs/super.c:1764
do_new_mount+0x24b/0xa40 fs/namespace.c:3377
init_mount+0xd2/0x120 fs/init.c:25
do_mount_root+0x97/0x230 init/do_mounts.c:166
mount_root_generic+0x195/0x3c0 init/do_mounts.c:205
prepare_namespace+0xc2/0x100 init/do_mounts.c:489
kernel_init_freeable+0x413/0x570 init/main.c:1566
kernel_init+0x1d/0x1c0 init/main.c:1443
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
-> #1 (bdev_lock){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747
bd_prepare_to_claim+0x1ba/0x480 block/bdev.c:510
truncate_bdev_range+0x4e/0x260 block/bdev.c:105
blkdev_fallocate+0x3ff/0x670 block/fops.c:792
vfs_fallocate+0x58e/0x700 fs/open.c:324
madvise_remove mm/madvise.c:1007 [inline]
madvise_vma_behavior mm/madvise.c:1031 [inline]
madvise_walk_vmas mm/madvise.c:1266 [inline]
do_madvise+0x15fe/0x3710 mm/madvise.c:1446
__do_sys_madvise mm/madvise.c:1459 [inline]
__se_sys_madvise mm/madvise.c:1457 [inline]
__x64_sys_madvise+0xa6/0xc0 mm/madvise.c:1457
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #0 (mapping.invalidate_lock#2){++++}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
down_read+0x46/0x2e0 kernel/locking/rwsem.c:1520
filemap_invalidate_lock_shared include/linux/fs.h:859 [inline]
page_cache_ra_unbounded+0xdc/0x770 mm/readahead.c:225
page_cache_sync_readahead include/linux/pagemap.h:1325 [inline]
ext4_readdir+0xb71/0x39d0 fs/ext4/dir.c:197
iterate_dir+0x1c2/0x580 fs/readdir.c:106
__do_sys_getdents64 fs/readdir.c:405 [inline]
__se_sys_getdents64+0xe9/0x260 fs/readdir.c:390
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
other info that might help us debug this:
Chain exists of:
mapping.invalidate_lock#2 --> &type->s_umount_key#31 --> &type->i_mutex_dir_key#3
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
rlock(&type->i_mutex_dir_key#3);
lock(&type->s_umount_key#31);
lock(&type->i_mutex_dir_key#3);
rlock(mapping.invalidate_lock#2);
*** DEADLOCK ***
2 locks held by syz-executor/9812:
#0: ffff88805ffc59c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040
#1: ffff8880595a2210 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: iterate_dir+0xcb/0x580 fs/readdir.c:99
stack backtrace:
CPU: 0 PID: 9812 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2025
Call Trace:
<TASK>
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
check_noncircular+0x2bd/0x3c0 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
down_read+0x46/0x2e0 kernel/locking/rwsem.c:1520
filemap_invalidate_lock_shared include/linux/fs.h:859 [inline]
page_cache_ra_unbounded+0xdc/0x770 mm/readahead.c:225
page_cache_sync_readahead include/linux/pagemap.h:1325 [inline]
ext4_readdir+0xb71/0x39d0 fs/ext4/dir.c:197
iterate_dir+0x1c2/0x580 fs/readdir.c:106
__do_sys_getdents64 fs/readdir.c:405 [inline]
__se_sys_getdents64+0xe9/0x260 fs/readdir.c:390
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f812cfc1553
Code: c1 66 0f 1f 44 00 00 48 83 c4 08 48 89 ef 5b 5d e9 52 3e f8 ff 66 90 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 c7 c2 a8 ff ff ff f7 d8
RSP: 002b:00007ffd226d5468 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00005555907c6600 RCX: 00007f812cfc1553
RDX: 0000000000008000 RSI: 00005555907c6600 RDI: 0000000000000005
RBP: 00005555907c65d4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000293 R12: ffffffffffffffa8
R13: 0000000000000010 R14: 00005555907c65d0 R15: 00007ffd226d7720
</TASK>
| Time | Kernel | Commit | Syzkaller | Config | Log | Report | Syz repro | C repro | VM info | Assets (help?) | Manager | Title |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2025/09/02 06:18 | linux-6.6.y | cc1a1c5b404a | 807a3b61 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-6-kasan | possible deadlock in page_cache_ra_unbounded | ||
| 2025/08/30 06:25 | linux-6.6.y | cc1a1c5b404a | 807a3b61 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-6-kasan | possible deadlock in page_cache_ra_unbounded |