[syzbot] [btrfs?] kernel BUG in mapping_try_invalidate (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: eb71ab2bf722 Merge tag 'bpf-fixes' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1749a202580000
kernel config: https://syzkaller.appspot.com/x/.config?x=70fe0401f305d8d4
dashboard link: https://syzkaller.appspot.com/bug?extid=bdad05f2e28a336132a6
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/222ddc146de5/disk-eb71ab2b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a5d8a5d85aad/vmlinux-eb71ab2b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1bac21c0baa2/bzImage-eb71ab2b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+bdad05...@syzkaller.appspotmail.com

blkdev_read_iter+0x311/0x440 block/fops.c:855
new_sync_read fs/read_write.c:493 [inline]
vfs_read+0x58b/0xa80 fs/read_write.c:574
ksys_read+0x156/0x270 fs/read_write.c:717
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 28 tgid 28 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1433 [inline]
__free_frozen_pages+0xfe3/0x1170 mm/page_alloc.c:2978
__tlb_remove_table_free mm/mmu_gather.c:228 [inline]
tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:291
rcu_do_batch kernel/rcu/tree.c:2617 [inline]
rcu_core kernel/rcu/tree.c:2869 [inline]
rcu_cpu_kthread+0x99e/0x1470 kernel/rcu/tree.c:2957
smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
------------[ cut here ]------------
kernel BUG at mm/filemap.c:2185!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 8836 Comm: syz.0.423 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:find_lock_entries+0xa8a/0xa90 mm/filemap.c:2184
Code: 8b 7c 24 18 48 c7 c6 a0 bd 57 8b e8 70 38 28 ff 90 0f 0b e8 58 cb c4 ff 48 8b 7c 24 18 48 c7 c6 40 b6 57 8b e8 57 38 28 ff 90 <0f> 0b 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90006de75c0 EFLAGS: 00010246
RAX: b8fe3e8dac16f000 RBX: ffffc90006de7a00 RCX: 0000000000000046
RDX: 0000000000000003 RSI: ffffffff8d7b842e RDI: ffff888024b95ac0
RBP: ffffc90006de7710 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1017124923 R12: ffffea00016a8000
R13: 0000000000000fce R14: 0000000000000000 R15: 0000000000000001
FS: 00007f85361366c0(0000) GS:ffff888126440000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f43dc4b7000 CR3: 0000000038050000 CR4: 00000000003526f0
Call Trace:
<TASK>
mapping_try_invalidate+0x1ae/0x4c0 mm/truncate.c:545
btrfs_get_bdev_and_sb+0x114/0x340 fs/btrfs/volumes.c:501
btrfs_open_one_device fs/btrfs/volumes.c:666 [inline]
open_fs_devices+0x1d6/0x1440 fs/btrfs/volumes.c:1248
btrfs_get_tree_super fs/btrfs/super.c:1928 [inline]
btrfs_get_tree_subvol fs/btrfs/super.c:2087 [inline]
btrfs_get_tree+0xbe8/0x1930 fs/btrfs/super.c:2121
vfs_get_tree+0x92/0x2a0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3763 [inline]
do_new_mount+0x341/0xd30 fs/namespace.c:3839
do_mount fs/namespace.c:4172 [inline]
__do_sys_mount fs/namespace.c:4361 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4338
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8537edda0a
Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8536135e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f8536135ee0 RCX: 00007f8537edda0a
RDX: 0000200000005100 RSI: 0000200000000300 RDI: 00007f8536135ea0
RBP: 0000200000005100 R08: 00007f8536135ee0 R09: 0000000000000016
R10: 0000000000000016 R11: 0000000000000246 R12: 0000200000000300
R13: 00007f8536135ea0 R14: 0000000000005102 R15: 0000200000000380
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:find_lock_entries+0xa8a/0xa90 mm/filemap.c:2184
Code: 8b 7c 24 18 48 c7 c6 a0 bd 57 8b e8 70 38 28 ff 90 0f 0b e8 58 cb c4 ff 48 8b 7c 24 18 48 c7 c6 40 b6 57 8b e8 57 38 28 ff 90 <0f> 0b 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90006de75c0 EFLAGS: 00010246
RAX: b8fe3e8dac16f000 RBX: ffffc90006de7a00 RCX: 0000000000000046
RDX: 0000000000000003 RSI: ffffffff8d7b842e RDI: ffff888024b95ac0
RBP: ffffc90006de7710 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1017124923 R12: ffffea00016a8000
R13: 0000000000000fce R14: 0000000000000000 R15: 0000000000000001
FS: 00007f85361366c0(0000) GS:ffff888126440000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f43dc4b7000 CR3: 0000000038050000 CR4: 00000000003526f0


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