Extracting prog: 7m24.582030905s
Minimizing prog: 33m45.911054704s
Simplifying prog options: 16m35.7235426s
Extracting C: 5m12.919704557s
Simplifying C: 0s
extracting reproducer from 1 programs
testing a last program of every proc
single: executing 1 programs separately with timeout 6m0s
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-syz_open_dev$loop-ioctl$BLKTRACESETUP-ioctl$BLKTRACETEARDOWN
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x3, 0x0, 0x0)
r0 = syz_open_dev$loop(&(0x7f0000000080), 0x4, 0x0)
ioctl$BLKTRACESETUP(r0, 0xc0481273, &(0x7f0000000000)={'\x00', 0x4, 0x80000001, 0x1, 0x4fdf, 0x1})
ioctl$BLKTRACETEARDOWN(r0, 0x1276, 0x0)
program crashed: INFO: task hung in blk_trace_setup
program crashed: INFO: task hung in blk_trace_ioctl
single: successfully extracted reproducer
found reproducer with 4 syscalls
minimizing guilty program
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-syz_open_dev$loop-ioctl$BLKTRACESETUP
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x3, 0x0, 0x0)
r0 = syz_open_dev$loop(&(0x7f0000000080), 0x4, 0x0)
ioctl$BLKTRACESETUP(r0, 0xc0481273, &(0x7f0000000000)={'\x00', 0x4, 0x80000001, 0x1, 0x4fdf, 0x1})
program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-syz_open_dev$loop-ioctl$BLKTRACETEARDOWN
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x3, 0x0, 0x0)
r0 = syz_open_dev$loop(&(0x7f0000000080), 0x4, 0x0)
ioctl$BLKTRACETEARDOWN(r0, 0x1276, 0x0)
program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-ioctl$BLKTRACESETUP-ioctl$BLKTRACETEARDOWN
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x3, 0x0, 0x0)
ioctl$BLKTRACESETUP(0xffffffffffffffff, 0xc0481273, &(0x7f0000000000)={'\x00', 0x4, 0x80000001, 0x1, 0x4fdf, 0x1})
ioctl$BLKTRACETEARDOWN(0xffffffffffffffff, 0x1276, 0x0)
program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-ioctl$BLKTRACESETUP-ioctl$BLKTRACETEARDOWN
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f0000000080), 0x4, 0x0)
ioctl$BLKTRACESETUP(r0, 0xc0481273, &(0x7f0000000000)={'\x00', 0x4, 0x80000001, 0x1, 0x4fdf, 0x1})
ioctl$BLKTRACETEARDOWN(r0, 0x1276, 0x0)
program crashed: INFO: task hung in blk_trace_setup
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-ioctl$BLKTRACESETUP-ioctl$BLKTRACETEARDOWN
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(0x0, 0x4, 0x0)
ioctl$BLKTRACESETUP(r0, 0xc0481273, &(0x7f0000000000)={'\x00', 0x4, 0x80000001, 0x1, 0x4fdf, 0x1})
ioctl$BLKTRACETEARDOWN(r0, 0x1276, 0x0)
program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-ioctl$BLKTRACESETUP-ioctl$BLKTRACETEARDOWN
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f0000000080), 0x4, 0x0)
ioctl$BLKTRACESETUP(r0, 0xc0481273, 0x0)
ioctl$BLKTRACETEARDOWN(r0, 0x1276, 0x0)
program did not crash
extracting C reproducer
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-ioctl$BLKTRACESETUP-ioctl$BLKTRACETEARDOWN
program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
simplifying guilty program options
testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-ioctl$BLKTRACESETUP-ioctl$BLKTRACETEARDOWN
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f0000000080), 0x4, 0x0)
ioctl$BLKTRACESETUP(r0, 0xc0481273, &(0x7f0000000000)={'\x00', 0x4, 0x80000001, 0x1, 0x4fdf, 0x1})
ioctl$BLKTRACETEARDOWN(r0, 0x1276, 0x0)
program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-ioctl$BLKTRACESETUP-ioctl$BLKTRACETEARDOWN
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f0000000080), 0x4, 0x0)
ioctl$BLKTRACESETUP(r0, 0xc0481273, &(0x7f0000000000)={'\x00', 0x4, 0x80000001, 0x1, 0x4fdf, 0x1})
ioctl$BLKTRACETEARDOWN(r0, 0x1276, 0x0)
program crashed: INFO: task hung in blk_trace_setup
extracting C reproducer
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-ioctl$BLKTRACESETUP-ioctl$BLKTRACETEARDOWN
program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-ioctl$BLKTRACESETUP-ioctl$BLKTRACETEARDOWN
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f0000000080), 0x4, 0x0)
ioctl$BLKTRACESETUP(r0, 0xc0481273, &(0x7f0000000000)={'\x00', 0x4, 0x80000001, 0x1, 0x4fdf, 0x1})
ioctl$BLKTRACETEARDOWN(r0, 0x1276, 0x0)
program crashed: INFO: task hung in blk_trace_ioctl
validation run: crashed=true
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-ioctl$BLKTRACESETUP-ioctl$BLKTRACETEARDOWN
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f0000000080), 0x4, 0x0)
ioctl$BLKTRACESETUP(r0, 0xc0481273, &(0x7f0000000000)={'\x00', 0x4, 0x80000001, 0x1, 0x4fdf, 0x1})
ioctl$BLKTRACETEARDOWN(r0, 0x1276, 0x0)
program crashed: INFO: task hung in blk_trace_ioctl
validation run: crashed=true
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-ioctl$BLKTRACESETUP-ioctl$BLKTRACETEARDOWN
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f0000000080), 0x4, 0x0)
ioctl$BLKTRACESETUP(r0, 0xc0481273, &(0x7f0000000000)={'\x00', 0x4, 0x80000001, 0x1, 0x4fdf, 0x1})
ioctl$BLKTRACETEARDOWN(r0, 0x1276, 0x0)
program crashed: INFO: task hung in blk_trace_setup
validation run: crashed=true
reproducing took 1h18m35.132519879s
repro crashed as (corrupted=false):
INFO: task syz.7.24:6625 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.24 state:D stack:28120 pid:6625 tgid:6624 ppid:6598 task_flags:0x480040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5354 [inline]
__schedule+0x165c/0x5520 kernel/sched/core.c:6966
__schedule_loop kernel/sched/core.c:7049 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7064
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7121
__mutex_lock_common kernel/locking/mutex.c:710 [inline]
__mutex_lock+0x856/0x1420 kernel/locking/mutex.c:794
blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
blk_debugfs_lock block/blk.h:749 [inline]
blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
blk_trace_ioctl+0x37f/0x920 kernel/trace/blktrace.c:937
blkdev_ioctl+0x4c1/0x740 block/ioctl.c:793
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f654e79c819
RSP: 002b:00007f654f66b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f654ea15fa0 RCX: 00007f654e79c819
RDX: 0000200000000000 RSI: 00000000c0481273 RDI: 0000000000000003
RBP: 00007f654e832c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f654ea16038 R14: 00007f654ea15fa0 R15: 00007ffd3bd54d88
INFO: task syz.7.24:6626 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.24 state:D stack:28456 pid:6626 tgid:6624 ppid:6598 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5354 [inline]
__schedule+0x165c/0x5520 kernel/sched/core.c:6966
__schedule_loop kernel/sched/core.c:7049 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7064
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7121
__mutex_lock_common kernel/locking/mutex.c:710 [inline]
__mutex_lock+0x856/0x1420 kernel/locking/mutex.c:794
blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
blk_trace_remove kernel/trace/blktrace.c:561 [inline]
blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
blkdev_common_ioctl+0x13a7/0x3250 block/ioctl.c:724
blkdev_ioctl+0x528/0x740 block/ioctl.c:798
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f654e79c819
RSP: 002b:00007f654f64a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f654ea16090 RCX: 00007f654e79c819
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007f654e832c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f654ea16128 R14: 00007f654ea16090 R15: 00007ffd3bd54d88
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e95d260 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e95d260 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e95d260 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5597:
#0: ffff8880332300a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
2 locks held by syz.6.23/6527:
1 lock held by syz.7.24/6625:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.7.24/6626:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.8.25/6654:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.8.25/6655:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.9.26/6754:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.9.26/6755:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.0.27/6885:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.0.27/6886:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.1.28/7141:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.1.28/7143:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.2.29/7393:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.2.29/7394:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.3.30/7618:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.3.30/7619:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.4.31/7868:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.4.31/7870:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 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
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6527 Comm: syz.6.23 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:114 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:128 [inline]
RIP: 0010:lock_release+0x94/0x3c0 kernel/locking/lockdep.c:5885
Code: 85 0d 02 00 00 65 4c 8b 3d c1 1e 9f 11 41 83 bf 4c 0b 00 00 00 0f 85 f7 01 00 00 49 81 3e 80 93 05 94 0f 84 ea 01 00 00 9c 5b 48 c7 c7 72 02 12 8e e8 ef ee 17 0a 65 ff 05 38 64 9f 11 c7 44
RSP: 0018:ffffc900033174d8 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000202 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8c2a9240 RDI: ffffffff8c2a9200
RBP: ffff88801fca96e4 R08: ffff88801fca96a7 R09: 1ffff11003f952d4
R10: dffffc0000000000 R11: ffffed1003f952d5 R12: 00000000000a21e3
R13: ffffffff82399e8e R14: ffffffff8e95d260 R15: ffff88802c91db80
FS: 00007f1d824b26c0(0000) GS:ffff888125304000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd26a12048 CR3: 000000005d6d0000 CR4: 00000000003526f0
Call Trace:
rcu_lock_release include/linux/rcupdate.h:322 [inline]
rcu_read_unlock include/linux/rcupdate.h:881 [inline]
__update_page_owner_free_handle+0x451/0x470 mm/page_owner.c:295
__reset_page_owner+0x85/0x1f0 mm/page_owner.c:321
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1402 [inline]
__free_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2943
relay_destroy_buf+0x10e/0x3a0 kernel/relay.c:199
relay_remove_buf kernel/relay.c:219 [inline]
kref_put include/linux/kref.h:65 [inline]
relay_close_buf kernel/relay.c:434 [inline]
relay_close+0x3c7/0x620 kernel/relay.c:663
blk_trace_free+0x3c/0x110 kernel/trace/blktrace.c:471
blk_trace_cleanup kernel/trace/blktrace.c:539 [inline]
__blk_trace_remove+0x22c/0x2c0 kernel/trace/blktrace.c:552
blk_trace_remove kernel/trace/blktrace.c:562 [inline]
blk_trace_ioctl+0x3a2/0x920 kernel/trace/blktrace.c:952
blkdev_common_ioctl+0x13a7/0x3250 block/ioctl.c:724
blkdev_ioctl+0x528/0x740 block/ioctl.c:798
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1d8159c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1d824b2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f1d81816090 RCX: 00007f1d8159c819
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007f1d81632c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1d81816128 R14: 00007f1d81816090 R15: 00007ffe04b57c08
final repro crashed as (corrupted=false):
INFO: task syz.7.24:6625 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.24 state:D stack:28120 pid:6625 tgid:6624 ppid:6598 task_flags:0x480040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5354 [inline]
__schedule+0x165c/0x5520 kernel/sched/core.c:6966
__schedule_loop kernel/sched/core.c:7049 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7064
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7121
__mutex_lock_common kernel/locking/mutex.c:710 [inline]
__mutex_lock+0x856/0x1420 kernel/locking/mutex.c:794
blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
blk_debugfs_lock block/blk.h:749 [inline]
blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
blk_trace_ioctl+0x37f/0x920 kernel/trace/blktrace.c:937
blkdev_ioctl+0x4c1/0x740 block/ioctl.c:793
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f654e79c819
RSP: 002b:00007f654f66b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f654ea15fa0 RCX: 00007f654e79c819
RDX: 0000200000000000 RSI: 00000000c0481273 RDI: 0000000000000003
RBP: 00007f654e832c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f654ea16038 R14: 00007f654ea15fa0 R15: 00007ffd3bd54d88
INFO: task syz.7.24:6626 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.24 state:D stack:28456 pid:6626 tgid:6624 ppid:6598 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5354 [inline]
__schedule+0x165c/0x5520 kernel/sched/core.c:6966
__schedule_loop kernel/sched/core.c:7049 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7064
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7121
__mutex_lock_common kernel/locking/mutex.c:710 [inline]
__mutex_lock+0x856/0x1420 kernel/locking/mutex.c:794
blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
blk_trace_remove kernel/trace/blktrace.c:561 [inline]
blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
blkdev_common_ioctl+0x13a7/0x3250 block/ioctl.c:724
blkdev_ioctl+0x528/0x740 block/ioctl.c:798
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f654e79c819
RSP: 002b:00007f654f64a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f654ea16090 RCX: 00007f654e79c819
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007f654e832c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f654ea16128 R14: 00007f654ea16090 R15: 00007ffd3bd54d88
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e95d260 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e95d260 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e95d260 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5597:
#0: ffff8880332300a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
2 locks held by syz.6.23/6527:
1 lock held by syz.7.24/6625:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.7.24/6626:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.8.25/6654:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.8.25/6655:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.9.26/6754:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.9.26/6755:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.0.27/6885:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.0.27/6886:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.1.28/7141:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.1.28/7143:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.2.29/7393:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.2.29/7394:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.3.30/7618:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.3.30/7619:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
1 lock held by syz.4.31/7868:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:749 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788
1 lock held by syz.4.31/7870:
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:737 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888026d09b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 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
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6527 Comm: syz.6.23 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:114 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:128 [inline]
RIP: 0010:lock_release+0x94/0x3c0 kernel/locking/lockdep.c:5885
Code: 85 0d 02 00 00 65 4c 8b 3d c1 1e 9f 11 41 83 bf 4c 0b 00 00 00 0f 85 f7 01 00 00 49 81 3e 80 93 05 94 0f 84 ea 01 00 00 9c 5b 48 c7 c7 72 02 12 8e e8 ef ee 17 0a 65 ff 05 38 64 9f 11 c7 44
RSP: 0018:ffffc900033174d8 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000202 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8c2a9240 RDI: ffffffff8c2a9200
RBP: ffff88801fca96e4 R08: ffff88801fca96a7 R09: 1ffff11003f952d4
R10: dffffc0000000000 R11: ffffed1003f952d5 R12: 00000000000a21e3
R13: ffffffff82399e8e R14: ffffffff8e95d260 R15: ffff88802c91db80
FS: 00007f1d824b26c0(0000) GS:ffff888125304000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd26a12048 CR3: 000000005d6d0000 CR4: 00000000003526f0
Call Trace:
rcu_lock_release include/linux/rcupdate.h:322 [inline]
rcu_read_unlock include/linux/rcupdate.h:881 [inline]
__update_page_owner_free_handle+0x451/0x470 mm/page_owner.c:295
__reset_page_owner+0x85/0x1f0 mm/page_owner.c:321
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1402 [inline]
__free_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2943
relay_destroy_buf+0x10e/0x3a0 kernel/relay.c:199
relay_remove_buf kernel/relay.c:219 [inline]
kref_put include/linux/kref.h:65 [inline]
relay_close_buf kernel/relay.c:434 [inline]
relay_close+0x3c7/0x620 kernel/relay.c:663
blk_trace_free+0x3c/0x110 kernel/trace/blktrace.c:471
blk_trace_cleanup kernel/trace/blktrace.c:539 [inline]
__blk_trace_remove+0x22c/0x2c0 kernel/trace/blktrace.c:552
blk_trace_remove kernel/trace/blktrace.c:562 [inline]
blk_trace_ioctl+0x3a2/0x920 kernel/trace/blktrace.c:952
blkdev_common_ioctl+0x13a7/0x3250 block/ioctl.c:724
blkdev_ioctl+0x528/0x740 block/ioctl.c:798
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1d8159c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1d824b2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f1d81816090 RCX: 00007f1d8159c819
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007f1d81632c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1d81816128 R14: 00007f1d81816090 R15: 00007ffe04b57c08