[syzbot] [bcachefs?] INFO: task hung in bch2_run_recovery_passes

[syzbot] [bcachefs?] INFO: task hung in bch2_run_recovery_passes

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    aaef6f251176 Merge branches 'for-next/core' and 'for-next/..
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=162817d4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=167a38bcf05390d5
dashboard link: https://syzkaller.appspot.com/bug?extid=c2294ae43bae606e3c7d
compiler:       Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
userspace arch: arm64
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=112817d4580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/dfd0a4db9e57/disk-aaef6f25.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/602c89e1c208/vmlinux-aaef6f25.xz
kernel image: https://storage.googleapis.com/syzbot-assets/82e8ab4e1b11/Image-aaef6f25.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/780ac1e01de6/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c2294ae43bae606e3c7d@syzkaller.appspotmail.com

INFO: task syz.1.22:6793 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc6-syzkaller-gaaef6f251176 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.22        state:D stack:0     pid:6793  tgid:6793  ppid:6662   task_flags:0x400140 flags:0x00000019
Call trace:
 __switch_to+0x414/0x834 arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x1414/0x2a28 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:6879
 schedule_timeout+0xac/0x270 kernel/time/sleep_timeout.c:75
 ___down_common+0x23c/0x374 kernel/locking/semaphore.c:268
 __down_common+0xc0/0x3a4 kernel/locking/semaphore.c:293
 __down+0x18/0x24 kernel/locking/semaphore.c:303
 down+0x94/0xe8 kernel/locking/semaphore.c:100
 bch2_run_recovery_passes+0x164/0x1f4 fs/bcachefs/recovery_passes.c:609
 bch2_fs_recovery+0x1df4/0x2fb4 fs/bcachefs/recovery.c:1050
 bch2_fs_start+0x940/0xbec fs/bcachefs/super.c:1213
 bch2_fs_get_tree+0x880/0x107c fs/bcachefs/fs.c:2488
 vfs_get_tree+0x90/0x28c fs/super.c:1804
 do_new_mount+0x228/0x814 fs/namespace.c:3902
 path_mount+0x5b4/0xde0 fs/namespace.c:4226
 do_mount fs/namespace.c:4239 [inline]
 __do_sys_mount fs/namespace.c:4450 [inline]
 __se_sys_mount fs/namespace.c:4427 [inline]
 __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4427
 __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+0x58/0x180 arch/arm64/kernel/entry-common.c:879
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Showing all locks held in the system:
2 locks held by kworker/u8:0/12:
1 lock held by khungtaskd/32:
 #0: ffff80008f869980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
5 locks held by kworker/u8:2/41:
 #0: ffff0000dafdd148 ((wq_completion)btree_update#272){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3212
 #1: ffff8000990f7bc0 ((work_completion)(&c->btree_interior_update_work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3212
 #2: ffff00010b404398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire+0x18/0x54 include/linux/srcu.h:160
 #3: ffff0001078f01b0 (bcachefs_btree){+.+.}-{0:0}, at: trans_set_locked+0x68/0x200 fs/bcachefs/btree_locking.h:205
 #4: ffff00010b400920 (&c->sb_lock){+.+.}-{4:4}, at: btree_update_new_nodes_mark_sb fs/bcachefs/btree_update_interior.c:609 [inline]
 #4: ffff00010b400920 (&c->sb_lock){+.+.}-{4:4}, at: btree_update_nodes_written fs/bcachefs/btree_update_interior.c:683 [inline]
 #4: ffff00010b400920 (&c->sb_lock){+.+.}-{4:4}, at: btree_interior_update_work+0x2e8/0x1d28 fs/bcachefs/btree_update_interior.c:867
2 locks held by pr/ttyAMA0/43:
2 locks held by kworker/u8:6/352:
 #0: ffff0000c0031148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3212
 #1: ffff80009bed7bc0 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3212
2 locks held by kworker/u8:8/4125:
5 locks held by kworker/u8:9/4137:
 #0: ffff0000fbc4b948 ((wq_completion)btree_update#271){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3212
 #1: ffff8000a0197bc0 ((work_completion)(&c->btree_interior_update_work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3212
 #2: ffff00010d304398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire+0x18/0x54 include/linux/srcu.h:160
 #3: ffff000104da81b0 (bcachefs_btree){+.+.}-{0:0}, at: trans_set_locked+0x68/0x200 fs/bcachefs/btree_locking.h:205
 #4: ffff00010d300920 (&c->sb_lock){+.+.}-{4:4}, at: btree_update_new_nodes_mark_sb fs/bcachefs/btree_update_interior.c:609 [inline]
 #4: ffff00010d300920 (&c->sb_lock){+.+.}-{4:4}, at: btree_update_nodes_written fs/bcachefs/btree_update_interior.c:683 [inline]
 #4: ffff00010d300920 (&c->sb_lock){+.+.}-{4:4}, at: btree_interior_update_work+0x2e8/0x1d28 fs/bcachefs/btree_update_interior.c:867
2 locks held by getty/6289:
 #0: ffff0000c19cc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80009ba3e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfa4 drivers/tty/n_tty.c:2222
3 locks held by kworker/1:3/6710:
2 locks held by syz.0.299/9979:
3 locks held by syz.5.300/9983:

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



---
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#syz undup

Re: [syzbot] [bcachefs?] INFO: task hung in bch2_run_recovery_passes

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    ae388edd4a8f Merge tag 'landlock-6.17-rc1' of git://git.ke..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15424cf0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=8004f1b1e0ae8198
dashboard link: https://syzkaller.appspot.com/bug?extid=c2294ae43bae606e3c7d
compiler:       Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1583f034580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1038d4a2580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/720dce21f23a/disk-ae388edd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a83240c628a9/vmlinux-ae388edd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1cabbf436747/bzImage-ae388edd.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/2b16c3a29557/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c2294ae43bae606e3c7d@syzkaller.appspotmail.com

INFO: task syz.4.23:6214 blocked for more than 143 seconds.
      Tainted: G        W           6.16.0-syzkaller-01056-gae388edd4a8f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.23        state:D stack:21160 pid:6214  tgid:6213  ppid:5960   task_flags:0x400140 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x165b/0x4c50 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6879
 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
 ___down_common kernel/locking/semaphore.c:268 [inline]
 __down_common+0x319/0x6a0 kernel/locking/semaphore.c:293
 down+0x80/0xd0 kernel/locking/semaphore.c:100
 bch2_run_recovery_passes+0x177/0x210 fs/bcachefs/recovery_passes.c:609
 bch2_fs_recovery+0x28c9/0x3a50 fs/bcachefs/recovery.c:1050
 bch2_fs_start+0xaaf/0xda0 fs/bcachefs/super.c:1213
 bch2_fs_get_tree+0xb39/0x1520 fs/bcachefs/fs.c:2488
 vfs_get_tree+0x92/0x2b0 fs/super.c:1815
 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4321
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0774e9014a
RSP: 002b:00007f07740f5e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f07740f5ef0 RCX: 00007f0774e9014a
RDX: 0000200000000080 RSI: 00002000000001c0 RDI: 00007f07740f5eb0
RBP: 0000200000000080 R08: 00007f07740f5ef0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000001c0
R13: 00007f07740f5eb0 R14: 000000000000f628 R15: 00002000000000c0
 </TASK>
INFO: task syz.0.26:6216 blocked for more than 143 seconds.
      Tainted: G        W           6.16.0-syzkaller-01056-gae388edd4a8f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.26        state:D stack:21160 pid:6216  tgid:6215  ppid:5947   task_flags:0x40[  344.100863][   T38] task:syz.0.26        state:D stack:21160 pid:6216  tgid:6215  ppid:5947   task_flags:0x400140 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x165b/0x4c50 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6879
 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
 ___down_common kernel/locking/semaphore.c:268 [inline]
 __down_common+0x319/0x6a0 kernel/locking/semaphore.c:293
 down+0x80/0xd0 kernel/locking/semaphore.c:100
 bch2_run_recovery_passes+0x177/0x210 fs/bcachefs/recovery_passes.c:609
 bch2_fs_recovery+0x28c9/0x3a50 fs/bcachefs/recovery.c:1050
 bch2_fs_start+0xaaf/0xda0 fs/bcachefs/super.c:1213
 bch2_fs_get_tree+0xb39/0x1520 fs/bcachefs/fs.c:2488
 vfs_get_tree+0x92/0x2b0 fs/super.c:1815
 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4321
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ffbf91d014a
RSP: 002b:00007ffbf8435e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffbf8435ef0 RCX: 00007ffbf91d014a
RDX: 0000200000000080 RSI: 00002000000001c0 RDI: 00007ffbf8435eb0
RBP: 0000200000000080 R08: 00007ffbf8435ef0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000001c0
R13: 00007ffbf8435eb0 R14: 000000000000f628 R15: 00002000000000c0
 </TASK>
INFO: task syz.3.28:6241 blocked for more than 143 seconds.
      Tainted: G        W           6.16.0-syzkaller-01056-gae388edd4a8f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.28        state:D stack:21160 pid:6241  tgid:6240  ppid:5956   task_flags:0x400140 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x165b/0x4c50 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6879
 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
 ___down_common kernel/locking/semaphore.c:268 [inline]
 __down_common+0x319/0x6a0 kernel/locking/semaphore.c:293
 down+0x80/0xd0 kernel/locking/semaphore.c:100
 bch2_run_recovery_passes+0x177/0x210 fs/bcachefs/recovery_passes.c:609
 bch2_fs_recovery+0x28c9/0x3a50 fs/bcachefs/recovery.c:1050
 bch2_fs_start+0xaaf/0xda0 fs/bcachefs/super.c:1213
 bch2_fs_get_tree+0xb39/0x1520 fs/bcachefs/fs.c:2488
 vfs_get_tree+0x92/0x2b0 fs/super.c:1815
 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4321
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f05843e014a
RSP: 002b:00007f058364de68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f058364def0 RCX: 00007f05843e014a
RDX: 0000200000000080 RSI: 00002000000001c0 RDI: 00007f058364deb0
RBP: 0000200000000080 R08: 00007f058364def0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000001c0
R13: 00007f058364deb0 R14: 000000000000f628 R15: 00002000000000c0
 </TASK>
INFO: task syz.1.30:6287 blocked for more than 143 seconds.
      Tainted: G        W           6.16.0-syzkaller-01056-gae388edd4a8f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.30        state:D stack:21160 pid:6287  tgid:6286  ppid:5950   task_flags:0x400140 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x165b/0x4c50 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6879
 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
 ___down_common kernel/locking/semaphore.c:268 [inline]
 __down_common+0x319/0x6a0 kernel/locking/semaphore.c:293
 down+0x80/0xd0 kernel/locking/semaphore.c:100
 bch2_run_recovery_passes+0x177/0x210 fs/bcachefs/recovery_passes.c:609
 bch2_fs_recovery+0x28c9/0x3a50 fs/bcachefs/recovery.c:1050
 bch2_fs_start+0xaaf/0xda0 fs/bcachefs/super.c:1213
 bch2_fs_get_tree+0xb39/0x1520 fs/bcachefs/fs.c:2488
 vfs_get_tree+0x92/0x2b0 fs/super.c:1815
 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4321
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3e578b014a
RSP: 002b:00007f3e56b1de68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f3e56b1def0 RCX: 00007f3e578b014a
RDX: 0000200000000080 RSI: 00002000000001c0 RDI: 00007f3e56b1deb0
RBP: 0000200000000080 R08: 00007f3e56b1def0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000001c0
R13: 00007f3e56b1deb0 R14: 000000000000f628 R15: 00002000000000c0
 </TASK>

Showing all locks held in the system:
4 locks held by pr/legacy/17:
1 lock held by khungtaskd/38:
 #0: ffffffff8d9aa300 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8d9aa300 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8d9aa300 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by kworker/u8:5/1011:
2 locks held by getty/5582:
 #0: ffff88823bf4c8a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003e932e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222
3 locks held by kworker/1:5/6095:
1 lock held by udevd/6527:
3 locks held by udevd/6529:
3 locks held by syz.0.218/7187:
2 locks held by syz.4.219/7189:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Tainted: G        W           6.16.0-syzkaller-01056-gae388edd4a8f #0 PREEMPT_{RT,(full)} 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
 watchdog+0xe9e/0xee0 kernel/hung_task.c:470
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17 Comm: pr/legacy Tainted: G        W           6.16.0-syzkaller-01056-gae388edd4a8f #0 PREEMPT_{RT,(full)} 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:409
Code: e8 9e 32 83 fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 ef 14 e1 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 8a ad b9 05 cc 44 89 f9 80 e1 07
RSP: 0018:ffffc90000167890 EFLAGS: 00000202
RAX: 1ffffffff326fe00 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffffff9937f7d0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff853b0150 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff9937f540 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881268fa000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ed5ffff CR3: 0000000036c16000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 serial_in drivers/tty/serial/8250/8250.h:137 [inline]
 serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline]
 wait_for_lsr+0x1a7/0x2f0 drivers/tty/serial/8250/8250_port.c:2094
 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3348 [inline]
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3371 [inline]
 serial8250_console_write+0x11bd/0x1b40 drivers/tty/serial/8250/8250_port.c:3456
 console_emit_next_record kernel/printk/printk.c:3118 [inline]
 console_flush_all+0x695/0xcd0 kernel/printk/printk.c:3226
 __console_flush_and_unlock+0xa4/0x240 kernel/printk/printk.c:3285
 legacy_kthread_func+0x13b/0x1a0 kernel/printk/printk.c:3638
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>


---
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Re: [syzbot] [bcachefs?] INFO: task hung in bch2_run_recovery_passes

[syzbot]

syzbot has bisected this issue to:

commit 39cea302f13a0a9dc4cf39248529a42e79d06842
Author: Kent Overstreet <kent.overstreet@linux.dev>
Date:   Fri May 9 21:01:05 2025 +0000

    bcachefs: bch2_check_bucket_backpointer_mismatch()

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=17590834580000
start commit:   ae388edd4a8f Merge tag 'landlock-6.17-rc1' of git://git.ke..
git tree:       upstream
final oops:     https://syzkaller.appspot.com/x/report.txt?x=14d90834580000
console output: https://syzkaller.appspot.com/x/log.txt?x=10d90834580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=8004f1b1e0ae8198
dashboard link: https://syzkaller.appspot.com/bug?extid=c2294ae43bae606e3c7d
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1583f034580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1038d4a2580000

Reported-by: syzbot+c2294ae43bae606e3c7d@syzkaller.appspotmail.com
Fixes: 39cea302f13a ("bcachefs: bch2_check_bucket_backpointer_mismatch()")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection