[moderation] [fs?] WARNING in file_seek_cur_needs_f_lock (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 9aa9b43d689e Merge branch 'for-next/core' into for-kernelci
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=10f8e88c580000
kernel config: https://syzkaller.appspot.com/x/.config?x=27f179c74d5c35cd
dashboard link: https://syzkaller.appspot.com/bug?extid=bb055f21f07d44ad4f1e
compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
userspace arch: arm64
CC: [bra...@kernel.org ja...@suse.cz linux-...@vger.kernel.org linux-...@vger.kernel.org vi...@zeniv.linux.org.uk]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/974f3ac1c6a5/disk-9aa9b43d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a5b5075d317f/vmlinux-9aa9b43d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2f0ba7fec19b/Image-9aa9b43d.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+bb055f...@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 8
------------[ cut here ]------------
WARNING: CPU: 0 PID: 7248 at fs/file.c:1202 file_seek_cur_needs_f_lock+0x124/0x138 fs/file.c:1201
Modules linked in:
CPU: 0 UID: 0 PID: 7248 Comm: syz.0.88 Not tainted 6.16.0-rc2-syzkaller-g9aa9b43d689e #0 PREEMPT
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : file_seek_cur_needs_f_lock+0x124/0x138 fs/file.c:1201
lr : file_seek_cur_needs_f_lock+0x124/0x138 fs/file.c:1201
sp : ffff80009c1a7c80
x29: ffff80009c1a7c80 x28: ffff0000d01ebd00 x27: 0000000000000004
x26: 1fffe0001a03d7a0 x25: 1ffff00013834fd6 x24: dfff800000000000
x23: 0000000000000001 x22: 0000000000000000 x21: bfffffffffffffff
x20: 0000000000000000 x19: ffff0000cf08cc40 x18: 0000000000000000
x17: 0000000000000000 x16: ffff80008aecb76c x15: 0000000000000001
x14: 1fffe00019e1199a x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000080000 x10: 00000000000000c8 x9 : ffff8000a4e89000
x8 : 00000000000000c9 x7 : ffff800080db6574 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff800080516ad4
x2 : 0000000000000000 x1 : 0000000000000008 x0 : 0000000000000000
Call trace:
file_seek_cur_needs_f_lock+0x124/0x138 fs/file.c:1201 (P)
generic_file_llseek_size+0xc0/0x454 fs/read_write.c:178
generic_file_llseek+0xc4/0xdc fs/read_write.c:248
vfs_llseek fs/read_write.c:389 [inline]
ksys_lseek fs/read_write.c:402 [inline]
__do_sys_lseek fs/read_write.c:412 [inline]
__se_sys_lseek fs/read_write.c:410 [inline]
__arm64_sys_lseek+0x13c/0x1c0 fs/read_write.c:410
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767
el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
irq event stamp: 1126
hardirqs last enabled at (1125): [<ffff8000801fd600>] local_daif_restore+0x1c/0x3c arch/arm64/include/asm/daifflags.h:75
hardirqs last disabled at (1126): [<ffff80008aec67ac>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:511
softirqs last enabled at (1120): [<ffff8000801fcf10>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (1118): [<ffff8000801fcedc>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.