INFO: task syz.3.2691:16732 blocked for more than 143 seconds.
Not tainted 6.14.0-rc3-syzkaller-00060-g6537cfb395f3 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.2691 state:D stack:26464 pid:16732 tgid:16731 ppid:5823 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5378 [inline]
__schedule+0xf43/0x5890 kernel/sched/core.c:6765
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6857
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914
__mutex_lock_common kernel/locking/mutex.c:662 [inline]
__mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730
sync_bdevs+0xfd/0x360 block/bdev.c:1246
ksys_sync+0xb3/0x150 fs/sync.c:105
__do_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe0e578cde9
RSP: 002b:00007fe0e666b038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fe0e59a5fa0 RCX: 00007fe0e578cde9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fe0e59a5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe0e59a5fa0 R15: 00007ffcdcda75e8
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e1bcc80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e1bcc80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8e1bcc80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746
2 locks held by kworker/u8:8/2959:
2 locks held by getty/5579:
#0: ffff8880368ba0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5824:
#0: ffffffff8e1c80f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:302
1 lock held by udevd/16103:
#0: ffff888025fcb4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe20 block/bdev.c:903
1 lock held by syz.3.2691/16732:
#0: ffff888025fcb4c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0xfd/0x360 block/bdev.c:1246
6 locks held by kworker/1:0/17014:
1 lock held by syz.2.3079/18366:
1 lock held by syz.5.3080/18369:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc3-syzkaller-00060-g6537cfb395f3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
watchdog+0xf62/0x12b0 kernel/hung_task.c:399
kthread+0x3af/0x750 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 18366 Comm: syz.2.3079 Not tainted 6.14.0-rc3-syzkaller-00060-g6537cfb395f3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3799 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3819 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3874 [inline]
RIP: 0010:__lock_acquire+0x15e4/0x3c40 kernel/locking/lockdep.c:5228
Code: c3 48 c1 e8 2d 49 89 c4 48 8d 04 c5 20 ac a7 96 48 89 c2 48 89 44 24 08 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 <0f> 85 16 26 00 00 48 bd 00 00 00 00 00 fc ff df 4c 8b 34 24 4a 8b
RSP: 0018:ffffc90003d57800 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: 255fd69911439148 RCX: ffffffff8195b4ce
RDX: 1ffffffff2d8d0d9 RSI: 0000000000000008 RDI: ffffffff96ec2cf8
RBP: 0000000000000001 R08: 0000000000000000 R09: fffffbfff2dd859f
R10: ffffffff96ec2cff R11: 0000000000000000 R12: 000000000003db55
R13: ffff88802eee8000 R14: 0000000000000005 R15: ffff88802eee8af0
FS: 00007fb6111616c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6c25979178 CR3: 000000004c208000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851
__might_fault mm/memory.c:6840 [inline]
__might_fault+0x11b/0x190 mm/memory.c:6833
_inline_copy_from_user include/linux/uaccess.h:162 [inline]
_copy_from_user+0x29/0xd0 lib/usercopy.c:18
copy_from_user include/linux/uaccess.h:212 [inline]
copy_msghdr_from_user+0x99/0x160 net/socket.c:2503
recvmsg_copy_msghdr net/socket.c:2759 [inline]
___sys_recvmsg+0xdc/0x1a0 net/socket.c:2831
do_recvmmsg+0x2f8/0x740 net/socket.c:2930
__sys_recvmmsg net/socket.c:3004 [inline]
__do_sys_recvmmsg net/socket.c:3027 [inline]
__se_sys_recvmmsg net/socket.c:3020 [inline]
__x64_sys_recvmmsg+0x239/0x290 net/socket.c:3020
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb61038cde9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb611161038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fb6105a5fa0 RCX: 00007fb61038cde9
RDX: 0000000000010106 RSI: 00004000000000c0 RDI: 0000000000000004
RBP: 00007fb61040e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb6105a5fa0 R15: 00007fffddf3c068