INFO: task syz.4.41:5147 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.41 state:D stack:25712 pid:5147 ppid:4984 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
schedule+0xb9/0x180 kernel/sched/core.c:6639
rwsem_down_write_slowpath+0xc99/0x1160 kernel/locking/rwsem.c:1189
mmap_write_lock include/linux/mmap_lock.h:71 [inline]
exit_mmap+0x253/0x970 mm/mmap.c:3258
__mmput+0x118/0x3a0 kernel/fork.c:1210
exit_mm+0x24d/0x350 kernel/exit.c:572
do_exit+0x958/0x2570 kernel/exit.c:874
do_group_exit+0x229/0x2e0 kernel/exit.c:1030
get_signal+0x1259/0x1340 kernel/signal.c:2880
arch_do_signal_or_restart+0xc4/0x1310 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd11a59aef9
RSP: 002b:00007fd11b44b0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fd11a805fa8 RCX: 00007fd11a59aef9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fd11a805fa8
RBP: 00007fd11a805fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd11a806038 R14: 00007fff4fedf5b0 R15: 00007fff4fedf698
INFO: task syz.1.49:5171 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.49 state:D stack:25712 pid:5171 ppid:4975 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
schedule+0xb9/0x180 kernel/sched/core.c:6639
rwsem_down_write_slowpath+0xc99/0x1160 kernel/locking/rwsem.c:1189
mmap_write_lock include/linux/mmap_lock.h:71 [inline]
exit_mmap+0x253/0x970 mm/mmap.c:3258
__mmput+0x118/0x3a0 kernel/fork.c:1210
exit_mm+0x24d/0x350 kernel/exit.c:572
do_exit+0x958/0x2570 kernel/exit.c:874
do_group_exit+0x229/0x2e0 kernel/exit.c:1030
get_signal+0x1259/0x1340 kernel/signal.c:2880
arch_do_signal_or_restart+0xc4/0x1310 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0cf639aef9
RSP: 002b:00007f0cf71bf0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f0cf6605fa8 RCX: 00007f0cf639aef9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f0cf6605fa8
RBP: 00007f0cf6605fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0cf6606038 R14: 00007ffdd2bc2a90 R15: 00007ffdd2bc2b78
INFO: task syz.0.48:5170 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.48 state:D stack:25712 pid:5170 ppid:4972 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
schedule+0xb9/0x180 kernel/sched/core.c:6639
rwsem_down_write_slowpath+0xc99/0x1160 kernel/locking/rwsem.c:1189
mmap_write_lock include/linux/mmap_lock.h:71 [inline]
exit_mmap+0x253/0x970 mm/mmap.c:3258
__mmput+0x118/0x3a0 kernel/fork.c:1210
exit_mm+0x24d/0x350 kernel/exit.c:572
do_exit+0x958/0x2570 kernel/exit.c:874
do_group_exit+0x229/0x2e0 kernel/exit.c:1030
get_signal+0x1259/0x1340 kernel/signal.c:2880
arch_do_signal_or_restart+0xc4/0x1310 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f281299aef9
RSP: 002b:00007f28137d50e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f2812c05fa8 RCX: 00007f281299aef9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2812c05fa8
RBP: 00007f2812c05fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2812c06038 R14: 00007ffd8a833780 R15: 00007ffd8a833868
INFO: task syz.3.50:5174 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.50 state:D stack:25312 pid:5174 ppid:4988 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
schedule+0xb9/0x180 kernel/sched/core.c:6639
rwsem_down_write_slowpath+0xc99/0x1160 kernel/locking/rwsem.c:1189
mmap_write_lock include/linux/mmap_lock.h:71 [inline]
exit_mmap+0x253/0x970 mm/mmap.c:3258
__mmput+0x118/0x3a0 kernel/fork.c:1210
exit_mm+0x24d/0x350 kernel/exit.c:572
do_exit+0x958/0x2570 kernel/exit.c:874
do_group_exit+0x229/0x2e0 kernel/exit.c:1030
get_signal+0x1259/0x1340 kernel/signal.c:2880
arch_do_signal_or_restart+0xc4/0x1310 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f05df99aef9
RSP: 002b:00007f05e08b50e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f05dfc05fa8 RCX: 00007f05df99aef9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f05dfc05fa8
RBP: 00007f05dfc05fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f05dfc06038 R14: 00007ffe35f4e8f0 R15: 00007ffe35f4e9d8
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2c170 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2c990 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8cb2b7e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2b7e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2b7e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527
2 locks held by kworker/u4:2/41:
1 lock held by klogd/3626:
2 locks held by udevd/3637:
#0: ffffffff8cbc5cd0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:594 [inline]
#0: ffffffff8cbc5cd0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1552 [inline]
#0: ffffffff8cbc5cd0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x2ee/0x1680 kernel/fork.c:1601
#1: ffff88807c2c1f58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff88807c2c1f58 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:595 [inline]
#1: ffff88807c2c1f58 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1552 [inline]
#1: ffff88807c2c1f58 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x308/0x1680 kernel/fork.c:1601
2 locks held by getty/4032:
#0: ffff88802fc26098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
1 lock held by syz-executor/4975:
#0: ffff888072e12e58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#0: ffff888072e12e58 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x253/0x970 mm/mmap.c:3258
1 lock held by syz-executor/4978:
#0: ffff8880269888d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#0: ffff8880269888d8 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x253/0x970 mm/mmap.c:3258
1 lock held by udevd/5049:
#0: ffff888076768158 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#0: ffff888076768158 (&mm->mmap_lock){++++}-{3:3}, at: __vm_munmap+0x15e/0x2d0 mm/mmap.c:2933
1 lock held by syz.4.41/5147:
#0: ffff88807c511058 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#0: ffff88807c511058 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x253/0x970 mm/mmap.c:3258
1 lock held by syz.1.49/5171:
#0: ffff88807c2c0158 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#0: ffff88807c2c0158 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x253/0x970 mm/mmap.c:3258
1 lock held by syz.0.48/5170:
#0: ffff888076769058 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#0: ffff888076769058 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x253/0x970 mm/mmap.c:3258
1 lock held by syz.3.50/5174:
#0: ffff8880767697d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#0: ffff8880767697d8 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x253/0x970 mm/mmap.c:3258
1 lock held by sed/5175:
#0: ffff88807676f1d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#0: ffff88807676f1d8 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x16c/0x2d0 mm/util.c:518
1 lock held by syz-executor/5177:
#0: ffffffff8cb544b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x5c7/0x2570 kernel/exit.c:834
2 locks held by syz-executor/5182:
#0: ffff8881432f4460 (sb_writers#10){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:402
#1: ffff888073f09fb0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:799 [inline]
#1: ffff888073f09fb0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: filename_create+0x20b/0x450 fs/namei.c:3927
7 locks held by syz-executor/5185:
#0: ffff88807b3b6460 (sb_writers#11){.+.+}-{0:0}, at: vfs_write+0x270/0x9a0 fs/read_write.c:580
#1: ffff88807e4f7c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1d8/0x520 fs/kernfs/file.c:343
#2: ffffffff8cb542c8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:442 [inline]
#2: ffffffff8cb542c8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xe5/0x220 kernel/cgroup/cgroup.c:1700
#3: ffffffff8c9c81b0 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2476 [inline]
#3: ffffffff8c9c81b0 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x186/0x610 kernel/cgroup/cgroup.c:2983
#4: ffffffff8cb544b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2478 [inline]
#4: ffffffff8cb544b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x19c/0x610 kernel/cgroup/cgroup.c:2983
#5: ffffffff8cb62948 (cpuset_mutex){+.+.}-{3:3}, at: cpuset_attach+0xb2/0x550 kernel/cgroup/cpuset.c:2668
#6: ffff88807676db58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#6: ffff88807676db58 (&mm->mmap_lock){++++}-{3:3}, at: mpol_rebind_mm+0xd3/0x3a0 mm/mempolicy.c:386
3 locks held by syz-executor/5187:
#0: ffff8881432f4460 (sb_writers#10){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:402
#1: ffff888073f09fb0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:799 [inline]
#1: ffff888073f09fb0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: filename_create+0x20b/0x450 fs/namei.c:3927
#2: ffffffff8cb542c8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:442 [inline]
#2: ffffffff8cb542c8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xe5/0x220 kernel/cgroup/cgroup.c:1700
1 lock held by syz.9.55/5304:
#0: ffffffff8cb544b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x5c7/0x2570 kernel/exit.c:834
1 lock held by syz.9.55/5305:
#0: ffffffff8cb544b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x5c7/0x2570 kernel/exit.c:834
1 lock held by syz.6.72/5306:
#0: ffffffff8cb544b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x5c7/0x2570 kernel/exit.c:834
1 lock held by syz.6.72/5307:
#0: ffffffff8cb544b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x5c7/0x2570 kernel/exit.c:834
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xf0e/0xf50 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11 Comm: kworker/u4:1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:preempt_count_add+0x13c/0x190 kernel/sched/core.c:5715
Code: 48 c7 c1 40 e1 bd 96 80 e1 07 80 c1 03 38 c1 0f 8c 00 ff ff ff 89 fb 48 c7 c7 40 e1 bd 96 e8 3b ad 7a 00 89 df e9 eb fe ff ff <48> c7 c1 40 e1 bd 96 80 e1 07 80 c1 03 38 c1 0f 8c 05 ff ff ff 89
RSP: 0018:ffffc90000107600 EFLAGS: 00000202
RAX: 0000000000000004 RBX: ffffc900001076c8 RCX: ffffffff96bde103
RDX: dffffc0000000000 RSI: ffffffff81d339bb RDI: 0000000000000001
RBP: 1ffff92000020ee0 R08: ffffc90000107790 R09: 0000000000000001
R10: dffffc0000000000 R11: fffff52000020ee5 R12: ffffffff81d339bb
R13: ffffc90000107a50 R14: dffffc0000000000 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8279959000 CR3: 0000000024458000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
unwind_next_frame+0x97/0x1fd0 arch/x86/kernel/unwind_orc.c:433
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
__kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:329
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4b/0x490 mm/slab.h:737
slab_alloc_node mm/slub.c:3359 [inline]
kmem_cache_alloc_node+0x1ad/0x310 mm/slub.c:3404
__alloc_skb+0xf9/0x7d0 net/core/skbuff.c:505
alloc_skb include/linux/skbuff.h:1303 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
nsim_dev_trap_report_work+0x24f/0xa80 drivers/net/netdevsim/dev.c:851
process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295