[v5.15] INFO: task hung in nilfs_segctor_thread (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 284087d4f7d5 Linux 5.15.158
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=11b25c5c980000
kernel config: https://syzkaller.appspot.com/x/.config?x=b0dd54e4b5171ebc
dashboard link: https://syzkaller.appspot.com/bug?extid=dde2ac79fd03faeefa55
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c2e33c1db6bf/disk-284087d4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d9f77284af1d/vmlinux-284087d4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a600323dd149/bzImage-284087d4.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+dde2ac...@syzkaller.appspotmail.com

INFO: task segctord:4026 blocked for more than 143 seconds.
Not tainted 5.15.158-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:segctord state:D stack:27768 pid: 4026 ppid: 2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
rwsem_down_write_slowpath+0xf0c/0x16a0 kernel/locking/rwsem.c:1165
nilfs_transaction_lock+0x25c/0x4f0 fs/nilfs2/segment.c:357
nilfs_segctor_thread_construct fs/nilfs2/segment.c:2525 [inline]
nilfs_segctor_thread+0x508/0x1130 fs/nilfs2/segment.c:2609
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
</TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c91fae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
1 lock held by klogd/2952:
2 locks held by getty/3259:
#0: ffff88814ad5d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002bab2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
1 lock held by syz-executor.2/3525:
#0: ffff8880535520e0 (&type->s_umount_key#107){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365
3 locks held by syz-executor.3/4018:
1 lock held by segctord/4026:
#0: ffff8880205e02a0 (&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_lock+0x25c/0x4f0 fs/nilfs2/segment.c:357

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.158-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
watchdog+0xe72/0xeb0 kernel/hung_task.c:295
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4018 Comm: syz-executor.3 Not tainted 5.15.158-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:__sanitizer_cov_trace_pc+0x3e/0x60 kernel/kcov.c:202
Code: c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 34 16 00 00 00 74 2c 8b 91 10 16 00 00 83 fa 02 75 21 48 8b 91 18 16 00 00 <48> 8b 32 48 8d 7e 01 8b 89 14 16 00 00 48 39 cf 73 08 48 89 44 f2
RSP: 0018:ffffc90004707138 EFLAGS: 00000246
RAX: ffffffff83ed1ee5 RBX: ffff88801baaaad0 RCX: ffff888059855940
RDX: ffffc9000354b000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffffc900047072f0 R08: ffffffff83ebae80 R09: ffffed100961b2f4
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920008e0e40
R13: 1ffff920008e0e4e R14: ffff88801bacf890 R15: dffffc0000000000
FS: 00007fb7c50d36c0(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c0022b4548 CR3: 00000000131b9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311
rcu_read_lock include/linux/rcupdate.h:739 [inline]
percpu_ref_put_many include/linux/percpu-refcount.h:317 [inline]
percpu_ref_put+0x1c/0x210 include/linux/percpu-refcount.h:338
blk_queue_exit block/blk-core.c:506 [inline]
__submit_bio+0x7ad/0x850 block/blk-core.c:920
__submit_bio_noacct_mq block/blk-core.c:997 [inline]
submit_bio_noacct+0x955/0xb30 block/blk-core.c:1027
submit_bio+0x2dd/0x560 block/blk-core.c:1089
blk_next_bio block/blk-lib.c:19 [inline]
__blkdev_issue_discard+0x46f/0x7f0 block/blk-lib.c:98
blkdev_issue_discard+0xfd/0x1d0 block/blk-lib.c:140
nilfs_sufile_trim_fs+0x100b/0x1380 fs/nilfs2/sufile.c:1179
nilfs_ioctl_trim_fs fs/nilfs2/ioctl.c:1071 [inline]
nilfs_ioctl+0x11f2/0x2490 fs/nilfs2/ioctl.c:1312
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fb7c6b60d69
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb7c50d30c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fb7c6c8ef80 RCX: 00007fb7c6b60d69
RDX: 0000000020000680 RSI: 00000000c0185879 RDI: 0000000000000004
RBP: 00007fb7c6bad49e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fb7c6c8ef80 R15: 00007fff7c347028
</TASK>


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