INFO: task syz-executor.2:10077 can't die for more than 143 seconds. task:syz-executor.2 state:D stack:28352 pid:10077 ppid: 8442 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4324 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5075 schedule+0xcf/0x270 kernel/sched/core.c:5154 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1868 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x168/0x270 kernel/sched/completion.c:138 io_sq_thread_finish+0x96/0x580 fs/io_uring.c:7152 io_sq_offload_create fs/io_uring.c:7929 [inline] io_uring_create fs/io_uring.c:9465 [inline] io_uring_setup+0x1fb2/0x2c20 fs/io_uring.c:9550 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x465ef9 RSP: 002b:00007f74524fb188 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465ef9 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 00000000000022c3 RBP: 00000000004bcd1c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fffc714866f R14: 00007f74524fb300 R15: 0000000000022000 INFO: task syz-executor.2:10077 blocked for more than 143 seconds. Not tainted 5.11.0-next-20210225-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:28352 pid:10077 ppid: 8442 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4324 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5075 schedule+0xcf/0x270 kernel/sched/core.c:5154 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1868 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x168/0x270 kernel/sched/completion.c:138 io_sq_thread_finish+0x96/0x580 fs/io_uring.c:7152 io_sq_offload_create fs/io_uring.c:7929 [inline] io_uring_create fs/io_uring.c:9465 [inline] io_uring_setup+0x1fb2/0x2c20 fs/io_uring.c:9550 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x465ef9 RSP: 002b:00007f74524fb188 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465ef9 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 00000000000022c3 RBP: 00000000004bcd1c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fffc714866f R14: 00007f74524fb300 R15: 0000000000022000 INFO: task iou-sqp-10077:10092 can't die for more than 143 seconds. task:iou-sqp-10077 state:D stack:30296 pid:10092 ppid: 8442 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4324 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5075 schedule+0xcf/0x270 kernel/sched/core.c:5154 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1868 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x168/0x270 kernel/sched/completion.c:138 io_sq_thread+0x27d/0x19a0 fs/io_uring.c:6731 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 INFO: task iou-sqp-10077:10092 blocked for more than 143 seconds. Not tainted 5.11.0-next-20210225-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:iou-sqp-10077 state:D stack:30296 pid:10092 ppid: 8442 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4324 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5075 schedule+0xcf/0x270 kernel/sched/core.c:5154 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1868 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x168/0x270 kernel/sched/completion.c:138 io_sq_thread+0x27d/0x19a0 fs/io_uring.c:6731 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Showing all locks held in the system: 1 lock held by khungtaskd/1668: #0: ffffffff8bf744e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6327 1 lock held by in:imklog/8123: #0: ffff888013c6c0f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:961 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1668 Comm: khungtaskd Not tainted 5.11.0-next-20210225-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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 8548 Comm: kworker/u4:0 Not tainted 5.11.0-next-20210225-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: phy8 ieee80211_iface_work RIP: 0010:compound_head include/linux/page-flags.h:187 [inline] RIP: 0010:virt_to_head_page include/linux/mm.h:880 [inline] RIP: 0010:kmem_cache_free+0x77/0x730 mm/slub.c:3177 Code: c1 e8 0c 4c 89 6c 24 30 48 c7 44 24 38 00 00 00 00 49 89 c4 48 b8 00 00 00 00 00 ea ff ff 49 c1 e4 06 49 01 c4 49 8b 44 24 08 <48> 8d 50 ff a8 01 4c 0f 45 e2 48 8d 54 24 38 e8 35 86 ff ff 84 c0 RSP: 0018:ffffc90002197bf8 EFLAGS: 00000282 RAX: dead000000000100 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88801be11c00 RSI: ffffc90002197c28 RDI: ffff8881406fbc80 RBP: ffff8881406fbc80 R08: 0000000000000000 R09: 000000000000002e R10: ffffffff813332fa R11: 000000000000003f R12: ffffea0000516540 R13: ffff888014595140 R14: dffffc0000000000 R15: 0000000000000080 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feea6f41278 CR3: 0000000011a8a000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:683 __kfree_skb net/core/skbuff.c:740 [inline] kfree_skb net/core/skbuff.c:757 [inline] kfree_skb+0x140/0x3f0 net/core/skbuff.c:751 ieee80211_iface_work+0x2cf/0x9e0 net/mac80211/iface.c:1451 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