INFO: task syz-executor.0:8932 blocked for more than 143 seconds. Not tainted 5.13.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:24816 pid: 8932 ppid: 8442 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4339 [inline] __schedule+0xb98/0x1120 kernel/sched/core.c:5147 schedule+0x14b/0x200 kernel/sched/core.c:5226 schedule_timeout+0x98/0x2c0 kernel/time/timer.c:1868 do_wait_for_common+0x2dd/0x450 kernel/sched/completion.c:85 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x48/0x60 kernel/sched/completion.c:138 __flush_work kernel/workqueue.c:3052 [inline] __cancel_work_timer+0x4dc/0x690 kernel/workqueue.c:3139 p9_conn_destroy net/9p/trans_fd.c:891 [inline] p9_fd_close+0x2a2/0x3c0 net/9p/trans_fd.c:921 p9_client_create+0xa28/0xf80 net/9p/client.c:1071 v9fs_session_init+0x1e6/0x18c0 fs/9p/v9fs.c:406 v9fs_mount+0x72/0x870 fs/9p/vfs_super.c:126 legacy_get_tree+0xea/0x180 fs/fs_context.c:592 vfs_get_tree+0x86/0x270 fs/super.c:1498 do_new_mount fs/namespace.c:2905 [inline] path_mount+0x196f/0x2be0 fs/namespace.c:3235 do_mount fs/namespace.c:3248 [inline] __do_sys_mount fs/namespace.c:3456 [inline] __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433 do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665d9 RSP: 002b:00007f7882bdd188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000056c1a8 RCX: 00000000004665d9 RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 00000000004bfcb9 R08: 0000000020000580 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c1a8 R13: 00007fff58f535cf R14: 00007f7882bdd300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1608: #0: ffffffff8cf15c40 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 arch/x86/pci/mmconfig_64.c:151 2 locks held by kworker/1:1/8584: #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7aa/0x10c0 kernel/workqueue.c:2248 #1: ffffc90001e5fd20 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x7e8/0x10c0 kernel/workqueue.c:2250 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1608 Comm: khungtaskd Not tainted 5.13.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x202/0x31e lib/dump_stack.c:120 nmi_cpu_backtrace+0x16c/0x190 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x191/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xcfb/0xd40 kernel/hung_task.c:294 kthread+0x39a/0x3c0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.13.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events nsim_dev_trap_report_work RIP: 0010:set_canary_byte mm/kfence/core.c:211 [inline] RIP: 0010:for_each_canary mm/kfence/core.c:246 [inline] RIP: 0010:kfence_guarded_alloc+0x5be/0xb60 mm/kfence/core.c:318 Code: 66 66 2e 0f 1f 84 00 00 00 00 00 90 44 89 eb 80 e3 07 80 f3 aa 4c 89 e8 48 c1 e8 03 48 ba 00 00 00 00 00 fc ff df 0f b6 04 10 <84> c0 75 22 41 88 5d 00 49 ff c5 41 80 3c 16 00 74 08 4c 89 ff e8 RSP: 0018:ffffc90000ca79a0 EFLAGS: 00000802 RAX: 0000000000000000 RBX: 000000003bd044aa RCX: ffff888012b38000 RDX: dffffc0000000000 RSI: ffff88823bd04f00 RDI: ffff88823bd04000 RBP: ffffc90000ca7ab0 R08: ffffffff81c715fc R09: ffffc90000ca78d0 R10: fffff52000194f0c R11: 0000000000000000 R12: ffff88823bd04000 R13: ffff88823bd044a0 R14: 1ffffffff21e25d8 R15: ffffffff90f12ec0 FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9253fb4000 CR3: 000000000cc8e000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kfence_alloc include/linux/kfence.h:123 [inline] slab_alloc_node mm/slub.c:2837 [inline] kmem_cache_alloc_node+0x338/0x380 mm/slub.c:2948 __alloc_skb+0xd8/0x580 net/core/skbuff.c:413 alloc_skb include/linux/skbuff.h:1107 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:513 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:570 [inline] nsim_dev_trap_report_work+0x274/0xb20 drivers/net/netdevsim/dev.c:611 process_one_work+0x833/0x10c0 kernel/workqueue.c:2275 worker_thread+0xac1/0x1300 kernel/workqueue.c:2421 kthread+0x39a/0x3c0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294