INFO: task syz-executor:2927 blocked for more than 143 seconds.
Not tainted 6.15.0-rc4-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:11352 pid:2927 tgid:2927 ppid:1 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x756/0xc10 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xac/0x140 kernel/sched/core.c:6860
schedule_timeout+0x2c/0x160 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common+0xfa/0x1e0 kernel/sched/completion.c:127
kthread_stop+0x7d/0x1d0 kernel/kthread.c:791
bch2_copygc_stop+0x1d/0xb0 fs/bcachefs/movinggc.c:438
__bch2_fs_read_only+0x31/0x1d0 fs/bcachefs/super.c:292
bch2_fs_read_only+0x18c/0x3b0 fs/bcachefs/super.c:378
__bch2_fs_stop+0x5d/0x2c0 fs/bcachefs/super.c:690
generic_shutdown_super+0x74/0x110 fs/super.c:642
bch2_kill_sb+0x11/0x20 fs/bcachefs/fs.c:2605
deactivate_locked_super+0x33/0x150 fs/super.c:473
cleanup_mnt+0x7c/0x130 fs/namespace.c:1435
task_work_run+0x84/0xb0 kernel/task_work.c:227
resume_user_mode_work+0x52/0x60 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x77/0xc0 kernel/entry/common.c:218
do_syscall_64+0x9c/0x180 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4ed011fcd7
RSP: 002b:00007ffeedcd5328 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f4ed01a0b55 RCX: 00007f4ed011fcd7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffeedcd53e0
RBP: 00007ffeedcd53e0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffeedcd6470
R13: 00007f4ed01a0b55 R14: 0000000000011f2b R15: 00007ffeedcd64b0
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff83b84b30 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff83b84b30 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff83b84b30 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x2e/0x100 kernel/locking/lockdep.c:6764
2 locks held by getty/1448:
#0: ffff888104eaf8a0 (&tty->ldisc_sem){....}-{0:0}, at: tty_ldisc_ref_wait+0x20/0x40 drivers/tty/tty_ldisc.c:243
#1: ffffc90002c8b2f0 (&ldata->atomic_read_lock){....}-{3:3}, at: n_tty_read+0x1c9/0x6f0 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/2920:
#0: ffff8881474750e0 (&type->s_umount_key#50){....}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff8881474750e0 (&type->s_umount_key#50){....}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff8881474750e0 (&type->s_umount_key#50){....}-{3:3}, at: deactivate_super+0x33/0x40 fs/super.c:505
#1: ffff88816a800278 (&c->state_lock){....}-{3:3}, at: __bch2_fs_stop+0x55/0x2c0 fs/bcachefs/super.c:689
2 locks held by syz-executor/2927:
#0: ffff8881053270e0 (&type->s_umount_key#50){....}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff8881053270e0 (&type->s_umount_key#50){....}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff8881053270e0 (&type->s_umount_key#50){....}-{3:3}, at: deactivate_super+0x33/0x40 fs/super.c:505
#1: ffff88812c280278 (&c->state_lock){....}-{3:3}, at: __bch2_fs_stop+0x55/0x2c0 fs/bcachefs/super.c:689
2 locks held by bch-copygc/loop/5014:
#0: ffff88812c284380 (&c->btree_trans_barrier){....}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#0: ffff88812c284380 (&c->btree_trans_barrier){....}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#0: ffff88812c284380 (&c->btree_trans_barrier){....}-{0:0}, at: bch2_trans_srcu_lock+0x2f/0x80 fs/bcachefs/btree_iter.c:3257
#1: ffff88812c2a66d0 (&c->gc_lock){....}-{3:3}, at: bch2_btree_update_start+0x254/0x860 fs/bcachefs/btree_update_interior.c:1186
2 locks held by syz.4.571/12505:
2 locks held by syz.0.572/12508:
5 locks held by bch-copygc/loop/12516:
2 locks held by syz.2.570/12519:
1 lock held by syz.5.574/12521:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc4-syzkaller #0 PREEMPT(undef)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0xa2/0xf0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x109/0x170 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x8e/0x140 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0x604/0x630 kernel/hung_task.c:437
kthread+0x200/0x230 kernel/kthread.c:464
ret_from_fork+0x32/0x40 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 12521 Comm: syz.5.574 Not tainted 6.15.0-rc4-syzkaller #0 PREEMPT(undef)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:exit_to_user_mode_prepare include/linux/entry-common.h:331 [inline]
RIP: 0010:irqentry_exit_to_user_mode+0x79/0xc0 kernel/entry/common.c:231
Code: a9 04 00 02 00 74 0b 48 89 df e8 02 0f 64 fe 4c 89 f8 a8 02 74 08 48 89 df e8 53 8d 80 fe e8 be 8d 80 fe e8 d9 8d 80 fe eb a2 52 92 80 fe e8 bd 92 80 fe e8 38 2e 7c fe 90 90 90 66 90 b9 01
RSP: 0000:ffffc900019fbf38 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffffc900019fbf58 RCX: ed75d38bd9692e00
RDX: ffff8881097c4800 RSI: ffffffff83629309 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000007
R10: 0000000000000001 R11: 000000000000000c R12: 0000000000000000
R13: 0000000000000000 R14: ffff88813b45d340 R15: 0000000000000000
FS: 00007f49138266c0(0000) GS:ffff8882b3358000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f490b882000 CR3: 000000012b730000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f4914480d46
Code: f0 72 6e 48 63 cd 48 01 c1 49 39 4f 08 72 4c 8d 4d ff 85 ed 74 33 66 0f 1f 44 00 00 48 39 f0 72 1b 4d 8b 07 49 89 c1 49 29 f1 <47> 0f b6 0c 08 45 84 c9 74 08 45 88 0c 00 49 8b 47 10 48 83 c0 01
RSP: 002b:00007f49138254a0 EFLAGS: 00010206
RAX: 000000000047c001 RBX: 00007f4913825540 RCX: 0000000000000025
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00007f49138255e0
RBP: 0000000000000102 R08: 00007f490b406000 R09: 000000000047c000
R10: 0000000000000000 R11: 00007f4913825550 R12: 0000000000000001
R13: 00007f491465c880 R14: 0000000000000000 R15: 00007f49138255e0