INFO: task syz-executor.3:19167 can't die for more than 143 seconds. task:syz-executor.3 state:D stack:27592 pid:19167 ppid: 8427 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4322 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5073 schedule+0xcf/0x270 kernel/sched/core.c:5152 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:775 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2216 do_new_mount_fc fs/namespace.c:2846 [inline] do_new_mount fs/namespace.c:2905 [inline] path_mount+0x14d6/0x1f90 fs/namespace.c:3233 do_mount fs/namespace.c:3246 [inline] __do_sys_mount fs/namespace.c:3454 [inline] __se_sys_mount fs/namespace.c:3431 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3431 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x465ef9 RSP: 002b:00007f7c87aae188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465ef9 RDX: 0000000020002100 RSI: 00000000200020c0 RDI: 0000000000000000 RBP: 00000000004bcd1c R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffe3290ac0f R14: 00007f7c87aae300 R15: 0000000000022000 INFO: task syz-executor.3:19167 blocked for more than 143 seconds. Not tainted 5.12.0-rc1-next-20210302-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:27592 pid:19167 ppid: 8427 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4322 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5073 schedule+0xcf/0x270 kernel/sched/core.c:5152 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:775 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2216 do_new_mount_fc fs/namespace.c:2846 [inline] do_new_mount fs/namespace.c:2905 [inline] path_mount+0x14d6/0x1f90 fs/namespace.c:3233 do_mount fs/namespace.c:3246 [inline] __do_sys_mount fs/namespace.c:3454 [inline] __se_sys_mount fs/namespace.c:3431 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3431 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x465ef9 RSP: 002b:00007f7c87aae188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465ef9 RDX: 0000000020002100 RSI: 00000000200020c0 RDI: 0000000000000000 RBP: 00000000004bcd1c R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffe3290ac0f R14: 00007f7c87aae300 R15: 0000000000022000 INFO: task syz-executor.3:19174 can't die for more than 144 seconds. task:syz-executor.3 state:R running task stack:28280 pid:19174 ppid: 8427 flags:0x00004006 Call Trace: Showing all locks held in the system: 1 lock held by khungtaskd/1653: #0: ffffffff8bf741e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6327 1 lock held by in:imklog/8124: #0: ffff888018228d70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:961 1 lock held by syz-executor.3/19167: #0: ffff88806c808ed0 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline] #0: ffff88806c808ed0 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: lock_mount+0x8a/0x2e0 fs/namespace.c:2216 4 locks held by syz-executor.3/19174: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1653 Comm: khungtaskd Not tainted 5.12.0-rc1-next-20210302-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+0xfa/0x151 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline] watchdog+0xd8e/0xf40 kernel/hung_task.c:338 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 12278 Comm: kworker/1:9 Not tainted 5.12.0-rc1-next-20210302-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:deref_stack_reg+0xf6/0x150 arch/x86/kernel/unwind_orc.c:355 Code: 0c f6 ff 41 89 c0 31 c0 45 85 c0 75 27 48 ba 00 00 00 00 00 fc ff df 48 89 d9 48 89 ef e8 12 f9 ff ff 48 c1 e9 03 80 3c 11 00 <75> 31 48 89 03 b8 01 00 00 00 48 83 c4 08 5b 5d 41 5c 41 5d c3 e8 RSP: 0018:ffffc90003aef768 EFLAGS: 00000246 RAX: ffffffff814a5cdc RBX: ffffc90003aef8b8 RCX: 1ffff9200075df17 RDX: dffffc0000000000 RSI: ffffc90003aefe48 RDI: ffffc90003aefe48 RBP: ffffc90003aefe48 R08: ffffffff8e3f48a8 R09: ffffffff8e3f48ac R10: 0000000000084087 R11: 0000000000000001 R12: ffffc90003aef870 R13: ffffc90003ae8000 R14: ffffc90003aef8c0 R15: ffffc90003aef870 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f36771cf000 CR3: 000000001f851000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0xbea/0x2000 arch/x86/kernel/unwind_orc.c:534 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:121 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:427 [inline] __kasan_slab_alloc+0x75/0x90 mm/kasan/common.c:460 kasan_slab_alloc include/linux/kasan.h:223 [inline] slab_post_alloc_hook mm/slab.h:516 [inline] slab_alloc_node mm/slub.c:2907 [inline] kmem_cache_alloc_node+0x16d/0x3c0 mm/slub.c:2943 __alloc_skb+0x20b/0x340 net/core/skbuff.c:412 alloc_skb include/linux/skbuff.h:1102 [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+0x2ac/0xbd0 drivers/net/netdevsim/dev.c:611 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294