INFO: task syz.4.93:6553 blocked for more than 143 seconds.
Not tainted 6.15.0-rc4-syzkaller-00319-g14c55b7bb0a8 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.93 state:D stack:28952 pid:6553 tgid:6499 ppid:5833 task_flags:0x400040 flags:0x00000004
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
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084
__down_read_common kernel/locking/rwsem.c:1248 [inline]
__down_read kernel/locking/rwsem.c:1261 [inline]
down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526
inode_lock_shared include/linux/fs.h:877 [inline]
lookup_slow+0x46/0x70 fs/namei.c:1833
walk_component+0x2d2/0x400 fs/namei.c:2138
lookup_last fs/namei.c:2636 [inline]
path_lookupat+0x163/0x430 fs/namei.c:2660
filename_lookup+0x212/0x570 fs/namei.c:2689
user_path_at+0x3a/0x60 fs/namei.c:3120
do_mount fs/namespace.c:4221 [inline]
__do_sys_mount fs/namespace.c:4435 [inline]
__se_sys_mount+0x2d3/0x410 fs/namespace.c:4412
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: 0033:0x7fdc19b8e969
RSP: 002b:00007fdc179f6038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fdc19db6080 RCX: 00007fdc19b8e969
RDX: 0000200000000140 RSI: 0000200000000080 RDI: 0000200000000040
RBP: 00007fdc19c10ab1 R08: 0000200000000180 R09: 0000000000000000
R10: 0000000000200000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fdc19db6080 R15: 00007ffcf28e3528
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
2 locks held by getty/5576:
#0: ffff8880306930a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002ffe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
5 locks held by syz.4.93/6500:
#0: ffff88807bb28420 (sb_writers#28){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
#1: ffff888079fba740 (&sb->s_type->i_mutex_key#30){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#1: ffff888079fba740 (&sb->s_type->i_mutex_key#30){++++}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline]
#1: ffff888079fba740 (&sb->s_type->i_mutex_key#30){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036
#2: ffff888079fbab28 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x2f2/0xb90 fs/bcachefs/fs.c:569
#3: ffff888055004228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#3: ffff888055004228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#3: ffff888055004228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3202
#4: ffff888055026590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179
1 lock held by syz.4.93/6553:
#0: ffff888079fba740 (&sb->s_type->i_mutex_key#30){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline]
#0: ffff888079fba740 (&sb->s_type->i_mutex_key#30){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833
2 locks held by bch-copygc/loop/6547:
1 lock held by dhcpcd/7219:
#0: ffff888079c08208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#0: ffff888079c08208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline]
#0: ffff888079c08208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1391
1 lock held by syz-executor/8052:
#0: ffff888079b280e0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline]
#0: ffff888079b280e0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff888079b280e0 (&type->s_umount_key#68){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505
3 locks held by kworker/1:8/8151:
#0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90002f27c60 (key_gc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90002f27c60 (key_gc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#2: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998
4 locks held by syz.1.275/8472:
1 lock held by dhcpcd-run-hook/8495:
4 locks held by dhcpcd-run-hook/8496:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc4-syzkaller-00319-g14c55b7bb0a8 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5809 Comm: syz-executor Not tainted 6.15.0-rc4-syzkaller-00319-g14c55b7bb0a8 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:syscall_return_via_sysret+0x1a/0x87
Code: 1c 00 00 e8 90 c2 4e 0a 84 c0 0f 84 38 15 00 00 66 90 b9 48 00 00 00 65 48 8b 15 99 5a 72 11 83 e2 fe 89 d0 48 c1 ea 20 0f 30 <41> 5f 41 5e 41 5d 41 5c 5d 5b 41 5b 41 5a 41 59 41 58 58 59 5a 5e
RSP: 0018:ffffc900041bff58 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000048
RDX: 0000000000000000 RSI: 00007fffffffefff RDI: ffffffff8bc0fea0
RBP: 0000000000000000 R08: ffffffff8f7daf77 R09: 1ffffffff1efb5ee
R10: dffffc0000000000 R11: fffffbfff1efb5ef R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000555560740500(0000) GS:ffff8881260fd000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff0f5adf000 CR3: 000000007a0a2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
RIP: 0033:0x7fc08c1c11e3
Code: 1f 84 00 00 00 00 00 83 ff 03 74 7b 83 ff 02 b8 fa ff ff ff 49 89 ca 0f 44 f8 80 3d 5e 33 1c 00 00 74 14 b8 e6 00 00 00 0f 05 d8 c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec 28 48 89 54 24 10
RSP: 002b:00007fff12ba67f8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fc08c1c11e3
RDX: 00007fff12ba6810 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000003bbb160 R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff12ba6c60
R13: 0000000000000004 R14: 00007fff12ba684c R15: 00007fff12ba68e0