INFO: task syz.1.378:8985 blocked for more than 143 seconds.
Not tainted 6.15.0-rc5-syzkaller-00275-gbec6f00f120e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.378 state:D stack:20904 pid:8985 tgid:8984 ppid:5820 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x168f/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
__closure_sync+0x163/0x220 lib/closure.c:146
bch2_wait_on_allocator fs/bcachefs/alloc_foreground.h:256 [inline]
bch2_btree_update_start+0x1193/0x14c0 fs/bcachefs/btree_update_interior.c:1251
bch2_btree_split_leaf+0x13c/0x8f0 fs/bcachefs/btree_update_interior.c:1879
bch2_trans_commit_error+0x1a8/0x1100 fs/bcachefs/btree_trans_commit.c:904
__bch2_trans_commit+0x779c/0x8ae0 fs/bcachefs/btree_trans_commit.c:1069
bch2_trans_commit fs/bcachefs/btree_update.h:195 [inline]
__bch2_create+0x887/0xb90 fs/bcachefs/fs.c:595
bch2_mknod fs/bcachefs/fs.c:752 [inline]
bch2_create+0x66/0xd0 fs/bcachefs/fs.c:766
lookup_open fs/namei.c:3701 [inline]
open_last_lookups fs/namei.c:3800 [inline]
path_openat+0x14f1/0x3830 fs/namei.c:4036
do_filp_open+0x1fa/0x410 fs/namei.c:4066
do_sys_openat2+0x121/0x1c0 fs/open.c:1429
do_sys_open fs/open.c:1444 [inline]
__do_sys_open fs/open.c:1452 [inline]
__se_sys_open fs/open.c:1448 [inline]
__x64_sys_open+0x11e/0x150 fs/open.c:1448
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcfe0d8e969
RSP: 002b:00007fcfe1c80038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fcfe0fb5fa0 RCX: 00007fcfe0d8e969
RDX: 000000000000009d RSI: 0000000000020440 RDI: 0000200000000280
RBP: 00007fcfe0e10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fcfe0fb5fa0 R15: 00007fffe8497458
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
1 lock held by klogd/5179:
#0: ffff8880b88399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605
2 locks held by getty/5580:
#0: ffff88807d4580a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036d32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/6618:
#0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998
5 locks held by syz.1.378/8985:
#0: ffff888063fa0420 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
#1: ffff88805be99810 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#1: ffff88805be99810 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline]
#1: ffff88805be99810 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036
#2: ffff88805be99bf8 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x2f2/0xb90 fs/bcachefs/fs.c:569
#3: ffff888043c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#3: ffff888043c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#3: ffff888043c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x806/0xda0 fs/bcachefs/btree_iter.c:3385
#4: ffff888043c26590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179
2 locks held by bch-copygc/loop/9049:
3 locks held by syz.8.727/11389:
2 locks held by syz.8.727/11412:
1 lock held by syz.7.729/11401:
#0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
2 locks held by udevadm/11416:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller-00275-gbec6f00f120e #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
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:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 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: 16 Comm: rcu_preempt Not tainted 6.15.0-rc5-syzkaller-00275-gbec6f00f120e #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:dequeue_entities+0x10e7/0x1510 kernel/sched/fair.c:7175
Code: be 04 00 00 00 e8 19 c7 8a 00 f0 ff 85 68 0b 00 00 0f 1f 44 00 00 41 0f b6 04 1c 84 c0 0f 85 d3 01 00 00 41 c7 07 00 00 00 00 <44> 89 e8 48 81 c4 b8 00 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc
RSP: 0018:ffffc90000157758 EFLAGS: 00000002
RAX: ffff8880b8939a01 RBX: 0000000000000009 RCX: dffffc0000000001
RDX: ffff88801b68da00 RSI: 0000000000000009 RDI: ffff8880b8939ac8
RBP: ffff8880b89399c0 R08: ffffffff8f7da977 R09: 1ffffffff1efb52e
R10: dffffc0000000000 R11: fffffbfff1efb52f R12: 0000000000000000
R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880b8939a00
FS: 0000000000000000(0000) GS:ffff888126200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3586cd CR3: 000000000dd36000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
dequeue_task_fair+0x2a1/0x690 kernel/sched/fair.c:7188
block_task kernel/sched/core.c:2145 [inline]
try_to_block_task kernel/sched/core.c:6602 [inline]
__schedule+0x5b8/0x4c70 kernel/sched/core.c:6716
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2046
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2248
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245