EXT4-fs (loop3): Test dummy encryption mode enabled
EXT4-fs (loop3): stripe (9) is not aligned with cluster size (16), stripe is disabled
EXT4-fs (loop3): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
======================================================
WARNING: possible circular locking dependency detected
6.6.101-syzkaller #0 Not tainted
------------------------------------------------------
syz.3.452/7652 is trying to acquire lock:
ffff88807d9d94a0 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:155
but task is already holding lock:
ffff88805ee3de10 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
ffff88805ee3de10 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0x9d/0x350 fs/ext4/file.c:294
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #5 (&sb->s_type->i_mutex_key#8){++++}-{3:3}:
down_read+0x46/0x2e0 kernel/locking/rwsem.c:1520
inode_lock_shared include/linux/fs.h:814 [inline]
ext4_bmap+0x4e/0x260 fs/ext4/inode.c:3139
bmap+0xa6/0xe0 fs/inode.c:1871
jbd2_journal_init_inode+0x87/0x3d0 fs/jbd2/journal.c:1711
ext4_open_inode_journal fs/ext4/super.c:5859 [inline]
ext4_load_journal fs/ext4/super.c:6018 [inline]
ext4_load_and_init_journal+0x315/0x2100 fs/ext4/super.c:4922
__ext4_fill_super fs/ext4/super.c:5398 [inline]
ext4_fill_super+0x415f/0x6620 fs/ext4/super.c:5729
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:3371
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
-> #4 (&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
-> #3 (&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:3371
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
-> #2 (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
blk_ioctl_zeroout block/ioctl.c:188 [inline]
blkdev_common_ioctl+0x1b92/0x23d0 block/ioctl.c:513
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
-> #1 (mapping.invalidate_lock#2){++++}-{3:3}:
down_read+0x46/0x2e0 kernel/locking/rwsem.c:1520
filemap_invalidate_lock_shared include/linux/fs.h:859 [inline]
filemap_fault+0x5db/0x15a0 mm/filemap.c:3330
__do_fault+0x13b/0x4e0 mm/memory.c:4243
do_read_fault mm/memory.c:4616 [inline]
do_fault mm/memory.c:4753 [inline]
do_pte_missing mm/memory.c:3688 [inline]
handle_pte_fault mm/memory.c:5025 [inline]
__handle_mm_fault mm/memory.c:5166 [inline]
handle_mm_fault+0x3886/0x4920 mm/memory.c:5331
faultin_page mm/gup.c:868 [inline]
__get_user_pages+0x5ea/0x1470 mm/gup.c:1167
populate_vma_page_range+0x2b6/0x370 mm/gup.c:1593
__mm_populate+0x24c/0x380 mm/gup.c:1696
mm_populate include/linux/mm.h:3317 [inline]
vm_mmap_pgoff+0x2e7/0x400 mm/util.c:561
ksys_mmap_pgoff+0x520/0x700 mm/mmap.c:1427
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 (&mm->mmap_lock){++++}-{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_killable+0x50/0x340 kernel/locking/rwsem.c:1543
mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:155
get_mmap_lock_carefully mm/memory.c:5367 [inline]
lock_mm_and_find_vma+0x2a3/0x300 mm/memory.c:5418
do_user_addr_fault+0x36c/0x12e0 arch/x86/mm/fault.c:1345
handle_page_fault arch/x86/mm/fault.c:1465 [inline]
exc_page_fault+0x67/0x110 arch/x86/mm/fault.c:1521
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608
fault_in_readable+0xd0/0x160 mm/gup.c:1904
fault_in_iov_iter_readable+0xbf/0x2e0 lib/iov_iter.c:216
generic_perform_write+0x1f2/0x5b0 mm/filemap.c:4006
ext4_buffered_write_iter+0xcc/0x350 fs/ext4/file.c:299
ext4_file_write_iter+0x1d9/0x1870 fs/ext4/file.c:-1
call_write_iter include/linux/fs.h:2018 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x43b/0x940 fs/read_write.c:584
ksys_write+0x147/0x250 fs/read_write.c:637
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:
&mm->mmap_lock --> &type->s_umount_key#31 --> &sb->s_type->i_mutex_key#8
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sb->s_type->i_mutex_key#8);
lock(&type->s_umount_key#31);
lock(&sb->s_type->i_mutex_key#8);
rlock(&mm->mmap_lock);
*** DEADLOCK ***
3 locks held by syz.3.452/7652:
#0: ffff88802ee545c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1042
#1: ffff88807cace418 (sb_writers#4){.+.+}-{0:0}, at: vfs_write+0x20e/0x940 fs/read_write.c:580
#2: ffff88805ee3de10 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#2: ffff88805ee3de10 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0x9d/0x350 fs/ext4/file.c:294
stack backtrace:
CPU: 0 PID: 7652 Comm: syz.3.452 Not tainted 6.6.101-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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_killable+0x50/0x340 kernel/locking/rwsem.c:1543
mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:155
get_mmap_lock_carefully mm/memory.c:5367 [inline]
lock_mm_and_find_vma+0x2a3/0x300 mm/memory.c:5418
do_user_addr_fault+0x36c/0x12e0 arch/x86/mm/fault.c:1345
handle_page_fault arch/x86/mm/fault.c:1465 [inline]
exc_page_fault+0x67/0x110 arch/x86/mm/fault.c:1521
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0010:fault_in_readable+0xd0/0x160 mm/gup.c:1905
Code: c6 b4 bf ff 4d 89 f4 49 81 cc ff 0f 00 00 4d 89 f7 49 01 dc 49 81 e4 00 f0 ff ff 4d 39 e6 77 44 e8 a5 b4 bf ff 4d 39 e7 74 47 <41> 8a 07 88 44 24 07 49 81 c7 00 10 00 00 4d 39 e7 74 07 e8 88 b4
RSP: 0018:ffffc90003547950 EFLAGS: 00050287
RAX: ffffffff81c5e0eb RBX: 0000000000001000 RCX: 0000000000080000
RDX: ffffc9000d3bc000 RSI: 000000000006a0b1 RDI: 000000000006a0b2
RBP: dffffc0000000000 R08: ffff888025533c00 R09: 0000000000000002
R10: 0000000000000005 R11: 0000000000000002 R12: 000020000002c000
R13: 0000000000000000 R14: 000020000002a040 R15: 000020000002b000
fault_in_iov_iter_readable+0xbf/0x2e0 lib/iov_iter.c:216
generic_perform_write+0x1f2/0x5b0 mm/filemap.c:4006
ext4_buffered_write_iter+0xcc/0x350 fs/ext4/file.c:299
ext4_file_write_iter+0x1d9/0x1870 fs/ext4/file.c:-1
call_write_iter include/linux/fs.h:2018 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x43b/0x940 fs/read_write.c:584
ksys_write+0x147/0x250 fs/read_write.c:637
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: 0033:0x7fc78478eb69
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc78567d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fc7849b5fa0 RCX: 00007fc78478eb69
RDX: 000000000208e24b RSI: 0000200000000040 RDI: 0000000000000004
RBP: 00007fc784811df1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fc7849b5fa0 R15: 00007ffc8d01fce8
</TASK>
----------------
Code disassembly (best guess), 1 bytes skipped:
0: b4 bf mov $0xbf,%ah
2: ff 4d 89 decl -0x77(%rbp)
5: f4 hlt
6: 49 81 cc ff 0f 00 00 or $0xfff,%r12
d: 4d 89 f7 mov %r14,%r15
10: 49 01 dc add %rbx,%r12
13: 49 81 e4 00 f0 ff ff and $0xfffffffffffff000,%r12
1a: 4d 39 e6 cmp %r12,%r14
1d: 77 44 ja 0x63
1f: e8 a5 b4 bf ff call 0xffbfb4c9
24: 4d 39 e7 cmp %r12,%r15
27: 74 47 je 0x70
* 29: 41 8a 07 mov (%r15),%al <-- trapping instruction
2c: 88 44 24 07 mov %al,0x7(%rsp)
30: 49 81 c7 00 10 00 00 add $0x1000,%r15
37: 4d 39 e7 cmp %r12,%r15
3a: 74 07 je 0x43
3c: e8 .byte 0xe8
3d: 88 .byte 0x88
3e: b4 .byte 0xb4