INFO: task syz-executor239:8097 blocked for more than 140 seconds. Not tainted 4.19.179-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor239 D28072 8097 8086 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 schedule_timeout+0x92d/0xfe0 kernel/time/timer.c:1794 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common+0x29c/0x470 kernel/sched/completion.c:115 __flush_work+0x4bb/0x8b0 kernel/workqueue.c:2925 __cancel_work_timer+0x412/0x590 kernel/workqueue.c:3012 p9_conn_destroy net/9p/trans_fd.c:899 [inline] p9_fd_close+0x29c/0x520 net/9p/trans_fd.c:934 p9_client_create+0x901/0x12e0 net/9p/client.c:1084 v9fs_session_init+0x1dd/0x1770 fs/9p/v9fs.c:421 v9fs_mount+0x73/0x910 fs/9p/vfs_super.c:135 mount_fs+0xa3/0x310 fs/super.c:1261 vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961 vfs_kern_mount fs/namespace.c:951 [inline] do_new_mount fs/namespace.c:2469 [inline] do_mount+0x113c/0x2f10 fs/namespace.c:2799 ksys_mount+0xcf/0x130 fs/namespace.c:3015 __do_sys_mount fs/namespace.c:3029 [inline] __se_sys_mount fs/namespace.c:3026 [inline] __x64_sys_mount+0xba/0x150 fs/namespace.c:3026 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x445c39 Code: Bad RIP value. RSP: 002b:00007f949bc47308 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000004cb518 RCX: 0000000000445c39 RDX: 0000000020000040 RSI: 0000000020000000 RDI: 0000000000000000 RBP: 00000000004cb510 R08: 00000000200001c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004cb51c R13: 000000000049b07c R14: 64663d736e617274 R15: 0000000000022000 Showing all locks held in the system: 2 locks held by kworker/0:1/14: #0: 0000000094edc173 ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2123 #1: 00000000335ecea8 ((work_completion)(&m->rq)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2127 1 lock held by khungtaskd/1567: #0: 00000000aa0a327e (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1567 Comm: khungtaskd Not tainted 4.19.179-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4691 Comm: systemd-journal Not tainted 4.19.179-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:149 [inline] RIP: 0010:unwind_next_frame+0x231/0x1c60 arch/x86/kernel/unwind_orc.c:422 Code: ff 39 d6 0f 83 df 10 00 00 48 ba 00 00 00 00 00 fc ff df 41 89 f0 4a 8d 3c 85 f8 27 17 8c 49 89 f9 49 c1 e9 03 45 0f b6 0c 11 <48> 89 fa 83 e2 07 83 c2 03 44 38 ca 7c 32 45 84 c9 74 2d 4c 89 44 RSP: 0018:ffff8880a0effa08 EFLAGS: 00000a07 RAX: 0000000000000000 RBX: 1ffff110141dff49 RCX: ffffffff8197d35f RDX: dffffc0000000000 RSI: 00000000000097d3 RDI: ffffffff8c198744 RBP: 0000000000000001 R08: 00000000000097d3 R09: 0000000000000000 R10: 0000000000074071 R11: 0000000000000001 R12: ffff8880a0effb38 R13: ffff8880a0effb25 R14: ffff8880a0effb28 R15: ffff8880a0effaf0 FS: 00007f7ba8b8d8c0(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7ba5f61578 CR3: 00000000a0ce8000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __save_stack_trace+0x9f/0x190 arch/x86/kernel/stacktrace.c:44 save_stack mm/kasan/kasan.c:448 [inline] set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:553 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc mm/slab.c:3397 [inline] kmem_cache_alloc+0x110/0x370 mm/slab.c:3557 getname_flags+0xce/0x590 fs/namei.c:140 do_sys_open+0x26c/0x520 fs/open.c:1079 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f7ba811d840 Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 RSP: 002b:00007ffd2aa1a738 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffd2aa1aa40 RCX: 00007f7ba811d840 RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 00005564bef656d0 RBP: 000000000000000d R08: 000000000000ffc0 R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff R13: 00005564bef58040 R14: 00007ffd2aa1aa00 R15: 00005564bef65720