INFO: task syz.0.687:6985 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.687 state:D stack:25520 pid:6985 ppid:4274 flags:0x00004004
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
io_schedule+0x7c/0xd0 kernel/sched/core.c:8799
bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
__wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49
out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64
wait_on_bit_io include/linux/wait_bit.h:101 [inline]
do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115
jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250
__ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235
ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945
__ext4_mark_inode_dirty+0x161/0x760 fs/ext4/inode.c:6119
ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156
__mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500
generic_update_time fs/inode.c:1946 [inline]
inode_update_time fs/inode.c:1959 [inline]
__file_update_time+0x21d/0x240 fs/inode.c:2147
file_update_time+0x2f3/0x370 fs/inode.c:2178
ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6274
do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009
do_shared_fault mm/memory.c:4694 [inline]
do_fault mm/memory.c:4762 [inline]
handle_pte_fault mm/memory.c:5029 [inline]
__handle_mm_fault mm/memory.c:5171 [inline]
handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292
do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338
handle_page_fault arch/x86/mm/fault.c:1429 [inline]
exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7fb3254727a9
RSP: 002b:00007ffd66925fa0 EFLAGS: 00010202
RAX: 0000001b2fb23000 RBX: ffffffff81e783a4 RCX: 0000001b2fb22ff8
RDX: 0000001b2f724220 RSI: 0000000000000008 RDI: 00007fb326355720
RBP: 00000000000001d8 R08: 00007fb325810000 R09: 00007fb325812000
R10: 0000000081e783a8 R11: 0000000000000011 R12: 00007fb325826128
R13: 000000000000e2d4 R14: ffffffff81e78351 R15: 00007fb326355720
INFO: task syz.6.691:6996 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.691 state:D stack:27632 pid:6996 ppid:6135 flags:0x00004004
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
io_schedule+0x7c/0xd0 kernel/sched/core.c:8799
bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
__wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49
out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64
wait_on_bit_io include/linux/wait_bit.h:101 [inline]
do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115
jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250
__ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235
ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945
__ext4_mark_inode_dirty+0x161/0x760 fs/ext4/inode.c:6119
ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156
__mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500
generic_update_time fs/inode.c:1946 [inline]
inode_update_time fs/inode.c:1959 [inline]
__file_update_time+0x21d/0x240 fs/inode.c:2147
file_update_time+0x2f3/0x370 fs/inode.c:2178
ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6274
do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009
do_shared_fault mm/memory.c:4694 [inline]
do_fault mm/memory.c:4762 [inline]
handle_pte_fault mm/memory.c:5029 [inline]
__handle_mm_fault mm/memory.c:5171 [inline]
handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292
do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338
handle_page_fault arch/x86/mm/fault.c:1429 [inline]
exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7fc03686baa3
RSP: 002b:00007ffd53f88160 EFLAGS: 00010246
RAX: 00000000003ffde8 RBX: 0000000000000000 RCX: 0000001b33264000
RDX: 0000001b33224000 RSI: 0000000000400000 RDI: 00007fc036be0708
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffd53f883f0
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2e5b0 (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: ffffffff8cb2edd0 (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: ffffffff8cb2dc20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2dc20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2dc20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527
6 locks held by kworker/u4:4/57:
#0: ffff888142690138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc90001587d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#2: ffff88814dca20e0 (&type->s_umount_key#32){++++}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:415
#3: ffff88814dca4c18 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x213/0x2e70 fs/ext4/inode.c:2717
#4: ffff88814dca6990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
#5: ffff8880720d20a0 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x914/0x1a90 fs/ext4/inode.c:674
2 locks held by getty/4030:
#0: ffff88802f11c098 (&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
3 locks held by syz-executor/4260:
#0: ffff88807bd2a6d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88807bd2a6d8 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
#0: ffff88807bd2a6d8 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline]
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline]
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273
#2: ffff88814dca6990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
3 locks held by kworker/u4:7/4344:
4 locks held by kworker/u4:13/4637:
#0: ffff8880b8e3acd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x98/0x130 kernel/sched/core.c:546
#1: ffff8880b8f27888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x400/0x740 kernel/sched/psi.c:999
#2: ffff8880b8f28458 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999
#3: ffffffff96ec33d8 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x68/0x4f0 lib/debugobjects.c:747
4 locks held by kworker/u4:15/4910:
#0: ffff8880b8e3acd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x98/0x130 kernel/sched/core.c:546
#1: ffff8880b8f27888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x400/0x740 kernel/sched/psi.c:999
#2: ffff8880b8f28458 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999
#3: ffffffff96e39cc0 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x68/0x4f0 lib/debugobjects.c:747
3 locks held by syz.0.687/6985:
#0: ffff88801746f1d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88801746f1d8 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
#0: ffff88801746f1d8 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline]
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline]
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273
#2: ffff88814dca6990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
3 locks held by syz.6.691/6996:
#0: ffff88807b2f71d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88807b2f71d8 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
#0: ffff88807b2f71d8 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline]
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline]
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273
#2: ffff88814dca6990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
3 locks held by syz.1.679/7002:
#0: ffff88807b2f1058 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88807b2f1058 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
#0: ffff88807b2f1058 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline]
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline]
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273
#2: ffff88814dca6990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
3 locks held by syz.4.689/7006:
#0: ffff88807d7488d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88807d7488d8 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
#0: ffff88807d7488d8 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline]
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline]
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273
#2: ffff88814dca6990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
3 locks held by syz.2.690/7011:
#0: ffff888018371058 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff888018371058 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
#0: ffff888018371058 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline]
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline]
#1: ffff88814dca2558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273
#2: ffff88814dca6990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
=============================================
NMI backtrace for cpu 0
CPU: 0 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4637 Comm: kworker/u4:13 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:orc_find arch/x86/kernel/unwind_orc.c:168 [inline]
RIP: 0010:unwind_next_frame+0x19b/0x1fd0 arch/x86/kernel/unwind_orc.c:448
Code: ef 08 8b 35 97 14 2d 0b 8d 46 ff 44 39 f8 0f 86 b0 16 00 00 44 89 f8 4c 8d 24 85 94 08 40 8f 4c 89 e0 48 c1 e8 03 0f b6 04 28 <84> c0 0f 85 23 18 00 00 45 8b 24 24 44 89 f8 ff c0 4c 8d 2c 85 94
RSP: 0018:ffffc900032c7620 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: ffffc900032c76c8 RCX: ffffffff96c1a100
RDX: dffffc0000000000 RSI: 000000000009607a RDI: 0000000000000001
RBP: dffffc0000000000 R08: ffffc900032c7790 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000658ee5 R12: ffffffff8f4355ec
R13: ffffc900032c7810 R14: ffffffff81d3561a R15: 000000000000d356
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056378593b168 CR3: 000000007dc15000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
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