INFO: task syz.3.20:5963 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.20 state:D s
task:syz.3.20 state:D stack:26632 pid:5963 tgid:5963 ppid:5774 task_flags:0x400140 flags:0x00080002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x16d9/0x5700 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7668
rt_mutex_slowlock_block+0x55e/0x690 kernel/locking/rtmutex.c:1670
__rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1787 [inline]
rt_mutex_slowlock+0x2d4/0x780 kernel/locking/rtmutex.c:1827
__rt_mutex_lock kernel/locking/rtmutex.c:1842 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:562 [inline]
mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:580
scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
scsi_scan drivers/scsi/scsi_sysfs.c:151 [inline]
store_scan+0x4aa/0x540 drivers/scsi/scsi_sysfs.c:191
kernfs_fop_write_iter+0x3a5/0x540 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x61e/0xbb0 fs/read_write.c:687
ksys_write+0x156/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f217a80e559
RSP: 002b:00007fff47132758 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f217aa95fa0 RCX: 00007f217a80e559
RDX: 0000000000000005 RSI: 0000200000000380 RDI: 0000000000000003
RBP: 00007f217a8a58b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f217aa95fac R14: 00007f217aa95fa0 R15: 00007f217aa95fa0
</TASK>
INFO: task syz.0.22:5964 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.22 state:D stack:27448 pid:5964 tgid:5964 ppid:5780 task_flags:0x400140 flags:0x00080002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x16d9/0x5700 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7668
rt_mutex_slowlock_block+0x55e/0x690 kernel/locking/rtmutex.c:1670
__rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1787 [inline]
rt_mutex_slowlock+0x2d4/0x780 kernel/locking/rtmutex.c:1827
__rt_mutex_lock kernel/locking/rtmutex.c:1842 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:562 [inline]
mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:580
scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
scsi_scan drivers/scsi/scsi_sysfs.c:151 [inline]
store_scan+0x4aa/0x540 drivers/scsi/scsi_sysfs.c:191
kernfs_fop_write_iter+0x3a5/0x540 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x61e/0xbb0 fs/read_write.c:687
ksys_write+0x156/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f09baafe559
RSP: 002b:00007ffc82a8a738 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f09bad85fa0 RCX: 00007f09baafe559
RDX: 0000000000000005 RSI: 0000200000000380 RDI: 0000000000000003
RBP: 00007f09bab958b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f09bad85fac R14: 00007f09bad85fa0 R15: 00007f09bad85fa0
</TASK>
Showing all locks held in the system:
locks held by khungtaskd/38: 1, last CPU#0:
#0: ffffffff8f1c3d00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8f1c3d00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8f1c3d00 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by kworker/u8:9/1050: 3, on CPU#0:
#0: ffff888033508938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff888033508938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff888033508938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#0: ffff888033508938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#1: ffffc900069e7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc900069e7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc900069e7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#1: ffffc900069e7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#2: ffffffff905d68b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
#2: ffffffff905d68b8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x123/0x16e0 net/ipv6/addrconf.c:4230
locks held by kworker/u8:12/2151: 3, last CPU#1:
#0: ffff888033115938 ((wq_completion)bat_events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff888033115938 ((wq_completion)bat_events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff888033115938 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#0: ffff888033115938 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#1: ffffc900089efc40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc900089efc40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc900089efc40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#1: ffffc900089efc40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#2: ffffffff8f059580 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3d/0x420 kernel/softirq.c:186
locks held by getty/5340: 2, on CPU#0:
#0: ffff88803342a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900044d32e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
locks held by syz.4.21/5962: 4, on CPU#0:
#0: ffff8880322d8510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff8880322d8510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff88803dd05078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.3.20/5963: 4, on CPU#0:
#0: ffff88805d656510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff88805d656510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888057d59478 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.0.22/5964: 4, on CPU#1:
#0: ffff888034ac2510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff888034ac2510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888036565478 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.6.24/6172: 4, on CPU#0:
#0: ffff88805fbfc510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff88805fbfc510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff88805ba33c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.5.23/6173: 4, on CPU#1:
#0: ffff888034f78510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff888034f78510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff88805dbdc078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.9.27/6174: 4, on CPU#1:
#0: ffff8880593a8510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff8880593a8510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888043916078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.8.26/6175: 4, on CPU#0:
#0: ffff888059450510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff888059450510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff88805dd88078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.7.25/6176: 4, on CPU#0:
#0: ffff88805e73c510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff88805e73c510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888043965c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.1.28/6310: 4, on CPU#0:
#0: ffff88803630a510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff88803630a510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff88805a2ef078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.2.29/6312: 4, on CPU#1:
#0: ffff888037560510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff888037560510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888057c8fc78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.0.30/6368: 4, on CPU#1:
#0: ffff88805f280510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff88805f280510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888064f13878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.3.31/6369: 4, on CPU#1:
#0: ffff88802d412510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff88802d412510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888033407c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.4.32/6370: 4, on CPU#1:
#0: ffff88805da0c510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff88805da0c510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888065ec4c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.6.33/6521: 4, on CPU#1:
#0: ffff888037412510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff888037412510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888069c96c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.5.34/6522: 4, on CPU#1:
#0: ffff888039532510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff888039532510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888064ff6878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.7.35/6609: 4, on CPU#0:
#0: ffff8880671fc510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff8880671fc510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888064b08078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.8.36/6619: 4, on CPU#0:
#0: ffff88805f710510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff88805f710510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff88805b5b5478 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.9.37/6624: 4, on CPU#0:
#0: ffff888034d64510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff888034d64510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888057f26078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz.1.38/6668: 4, on CPU#1:
#0: ffff888032a5a510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff888032a5a510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888039457878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz-executor/6669: 7, last CPU#0:
#0: ffffffff90b25848 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff90b25848 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff90b25848 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:595
#1: ffffffff905d68b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff905d68b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline]
#1: ffffffff905d68b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc10/0x1c30 net/core/rtnetlink.c:4219
#2: ffffffff8fb7c458 (gdp_mutex){+.+.}-{4:4}, at: get_device_parent+0x173/0x3a0 drivers/base/core.c:3338
#3: ffff8880b843ac48 ((lock)){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#3: ffff8880b843ac48 ((lock)){+.+.}-{3:3}, at: __radix_tree_preload+0x144/0x880 lib/radix-tree.c:334
#4: ffffffff8f1c3d00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#4: ffffffff8f1c3d00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#4: ffffffff8f1c3d00 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#4: ffffffff8f1c3d00 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e2/0x400 kernel/locking/spinlock_rt.c:57
#5: ffff88813ff77100 (&root->kernfs_idr_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#5: ffff88813ff77100 (&root->kernfs_idr_lock){+.+.}-{3:3}, at: __kernfs_new_node+0x11e/0xa70 fs/kernfs/dir.c:670
#6: ffffffff8f1c3d00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#6: ffffffff8f1c3d00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#6: ffffffff8f1c3d00 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#6: ffffffff8f1c3d00 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e2/0x400 kernel/locking/spinlock_rt.c:57
locks held by syz.2.39/6680: 4, on CPU#1:
#0: ffff88806b0e0510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff88806b0e0510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff88803ac2d478 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888029535c38 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffff8880272cc110 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_scan_host_selected+0x19f/0x6c0 drivers/scsi/scsi_scan.c:1916
locks held by syz-executor/6681: 1, on CPU#1:
#0: ffffffff905d68b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff905d68b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline]
#0: ffffffff905d68b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc10/0x1c30 net/core/rtnetlink.c:4219
locks held by syz-executor/6697: 2, on CPU#1:
#0: ffffffff90b3bd70 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff90b3bd70 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff90b3bd70 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:595
#1: ffffffff905d68b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff905d68b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline]
#1: ffffffff905d68b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc10/0x1c30 net/core/rtnetlink.c:4219
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x38b/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 17 Comm: pr/ttyS0 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:409
Code: e8 ae 89 63 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 af 4e d0 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07
RSP: 0018:ffffc900001678b8 EFLAGS: 00000202
RAX: 1ffffffff35d6300 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff85634f60 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff9aeb1f80 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124abb000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc0854bc560 CR3: 0000000035da8000 CR4: 00000000003526f0
Call Trace:
<TASK>
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x190/0x300 drivers/tty/serial/8250/8250_port.c:2013
serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3270 [inline]
__serial8250_console_fifo_write+0xd0/0x3f0 drivers/tty/serial/8250/8250_port.c:3345
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline]
__serial8250_console_write drivers/tty/serial/8250/8250_port.c:3432 [inline]
serial8250_console_write+0xaa2/0x1220 drivers/tty/serial/8250/8250_port.c:3496
nbcon_emit_next_record+0xef5/0x1a90 kernel/printk/nbcon.c:-1
nbcon_emit_one kernel/printk/nbcon.c:1157 [inline]
nbcon_kthread_func+0x679/0x880 kernel/printk/nbcon.c:1271
kthread+0x38b/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>