INFO: task syz-executor.2:13637 can't die for more than 143 seconds. task:syz-executor.2 state:D stack:27224 pid:13637 ppid: 8523 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8eb/0x21b0 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 rwsem_down_write_slowpath+0x809/0x1220 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+0x132/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:773 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2211 do_new_mount_fc fs/namespace.c:2839 [inline] do_new_mount fs/namespace.c:2898 [inline] path_mount+0x1678/0x1e70 fs/namespace.c:3227 do_mount fs/namespace.c:3240 [inline] __do_sys_mount fs/namespace.c:3448 [inline] __se_sys_mount fs/namespace.c:3425 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3425 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e159 RSP: 002b:00007f9179cc6c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e159 RDX: 0000000020002100 RSI: 00000000200020c0 RDI: 0000000000000000 RBP: 000000000119bfd0 R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffe3cfc519f R14: 00007f9179cc79c0 R15: 000000000119bf8c INFO: task syz-executor.2:13637 blocked for more than 143 seconds. Not tainted 5.10.0-next-20201215-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:27224 pid:13637 ppid: 8523 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8eb/0x21b0 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 rwsem_down_write_slowpath+0x809/0x1220 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+0x132/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:773 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2211 do_new_mount_fc fs/namespace.c:2839 [inline] do_new_mount fs/namespace.c:2898 [inline] path_mount+0x1678/0x1e70 fs/namespace.c:3227 do_mount fs/namespace.c:3240 [inline] __do_sys_mount fs/namespace.c:3448 [inline] __se_sys_mount fs/namespace.c:3425 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3425 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e159 RSP: 002b:00007f9179cc6c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e159 RDX: 0000000020002100 RSI: 00000000200020c0 RDI: 0000000000000000 RBP: 000000000119bfd0 R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffe3cfc519f R14: 00007f9179cc79c0 R15: 000000000119bf8c INFO: task syz-executor.2:13644 can't die for more than 144 seconds. task:syz-executor.2 state:R running task stack:27456 pid:13644 ppid: 8523 flags:0x00004006 Call Trace: Showing all locks held in the system: 1 lock held by khungtaskd/1665: #0: ffffffff8b78f920 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x28c kernel/locking/lockdep.c:6254 1 lock held by in:imklog/8388: #0: ffff888023acdc70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:923 2 locks held by agetty/8419: #0: ffff888023e5d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:266 #1: ffffc900012782e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x21d/0x1ac0 drivers/tty/n_tty.c:2158 1 lock held by syz-executor.2/13637: #0: ffff88806f021590 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline] #0: ffff88806f021590 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: lock_mount+0x8a/0x2e0 fs/namespace.c:2211 2 locks held by syz-executor.2/13644: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1665 Comm: khungtaskd Not tainted 5.10.0-next-20201215-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+0x107/0x163 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x3c/0xef 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+0xe75/0x1020 kernel/hung_task.c:338 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 245 Comm: kworker/u4:6 Not tainted 5.10.0-next-20201215-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: phy9 ieee80211_iface_work RIP: 0010:unwind_next_frame+0x27/0x2460 arch/x86/kernel/unwind_orc.c:418 Code: 0f 1f 00 48 b8 00 00 00 00 00 fc ff df 41 57 49 89 ff 41 56 41 55 41 54 55 53 48 81 ec b0 00 00 00 48 c7 44 24 50 b3 8a b5 41 <48> 8d 5c 24 50 48 c7 44 24 58 d1 56 f0 8a 48 c1 eb 03 48 c7 44 24 RSP: 0018:ffffc9000103f050 EFLAGS: 00000286 RAX: dffffc0000000000 RBX: ffffffff8160ce20 RCX: 0000000000000000 RDX: 1ffff92000207e52 RSI: ffffffff8149145d RDI: ffffc9000103f138 RBP: ffffc9000103f1c0 R08: ffffffff8e7f4a10 R09: 0000000000000001 R10: fffff52000207e32 R11: 0000000000000001 R12: ffffc9000103f1f0 R13: 0000000000000000 R14: ffff888012041b00 R15: ffffc9000103f138 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c0120cbf00 CR3: 000000001a466000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: 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:39 kasan_set_track mm/kasan/common.c:47 [inline] set_alloc_info mm/kasan/common.c:405 [inline] ____kasan_kmalloc mm/kasan/common.c:436 [inline] ____kasan_kmalloc.constprop.0+0xa0/0xd0 mm/kasan/common.c:408 kmalloc include/linux/slab.h:557 [inline] ieee802_11_parse_elems_crc+0x121/0x1030 net/mac80211/util.c:1473 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2039 [inline] ieee80211_rx_mgmt_probe_beacon+0x188/0x1760 net/mac80211/ibss.c:1612 ieee80211_ibss_rx_queued_mgmt+0xe2f/0x16d0 net/mac80211/ibss.c:1642 ieee80211_iface_work+0x7b0/0xa50 net/mac80211/iface.c:1423 process_one_work+0x98d/0x1630 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:296