Bluetooth: hci0 command 0x0406 tx timeout Bluetooth: hci1 command 0x0406 tx timeout Bluetooth: hci4 command 0x0406 tx timeout Bluetooth: hci5 command 0x0406 tx timeout Bluetooth: hci3 command 0x0406 tx timeout INFO: task systemd-udevd:4626 blocked for more than 140 seconds. Not tainted 4.14.281-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D25976 4626 1 0x00000304 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 lo_open+0x19/0xb0 drivers/block/loop.c:1634 __blkdev_get+0x306/0x1090 fs/block_dev.c:1470 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fae58e43840 RSP: 002b:00007ffd1093b0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffd1093b160 RCX: 00007fae58e43840 RDX: 000055d9c7e52fe3 RSI: 00000000000a0800 RDI: 000055d9c86caf50 RBP: 00007ffd1093b600 R08: 000055d9c7e52670 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd1093b270 R13: 000055d9c86b5010 R14: 000055d9c86b9320 R15: 00007ffd1093b140 INFO: task syz-executor.3:7970 blocked for more than 140 seconds. Not tainted 4.14.281-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D24832 7970 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f3494b81024 RSP: 002b:00007ffebd5d4b90 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ffebd5d4c90 RCX: 00007f3494b81024 RDX: 0000000000000002 RSI: 00007ffebd5d4cd0 RDI: 00000000ffffff9c RBP: 00007ffebd5d4cd0 R08: 0000000000000000 R09: 00007ffebd5d4aa0 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 0000000000022ab7 R14: 0000000000000012 R15: 00007ffebd5d4cd0 INFO: task syz-executor.4:7976 blocked for more than 140 seconds. Not tainted 4.14.281-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D25608 7976 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 lo_release+0x1b/0x190 drivers/block/loop.c:1677 __blkdev_put+0x5aa/0x800 fs/block_dev.c:1803 blkdev_close+0x86/0xb0 fs/block_dev.c:1875 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fd3c85f3d4b RSP: 002b:00007ffc60be28a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 00007ffc60be2940 RCX: 00007fd3c85f3d4b RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000000 R09: 00007ffc60be2750 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 R13: 0000000000022875 R14: 0000000000000012 R15: 00007ffc60be2980 INFO: task systemd-udevd:10040 blocked for more than 140 seconds. Not tainted 4.14.281-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D28712 10040 4626 0x00000300 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 lo_open+0x19/0xb0 drivers/block/loop.c:1634 __blkdev_get+0xa8c/0x1090 fs/block_dev.c:1537 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fae58e43840 RSP: 002b:00007ffd1093aa08 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000055d9c86ca7c0 RCX: 00007fae58e43840 RDX: 000055d9c7e52fe3 RSI: 00000000000a0800 RDI: 000055d9c86ca120 RBP: 00007ffd1093ab80 R08: 000055d9c7e52670 R09: 0000000000000010 R10: 000055d9c7e52d0c R11: 0000000000000246 R12: 00007ffd1093aad0 R13: 000055d9c86c6a10 R14: 0000000000000003 R15: 000000000000000e INFO: task syz-executor.0:10047 blocked for more than 140 seconds. Not tainted 4.14.281-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D26512 10047 7973 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 loop_reread_partitions drivers/block/loop.c:624 [inline] loop_clr_fd+0x9ca/0xc20 drivers/block/loop.c:1078 lo_ioctl+0x895/0x1cd0 drivers/block/loop.c:1424 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x540/0x1830 block/ioctl.c:594 block_ioctl+0xd9/0x120 fs/block_dev.c:1893 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fd85936fec7 RSP: 002b:00007fd857ce4ed8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd857ce4f20 RCX: 00007fd85936fec7 RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000006 RBP: 00007fd857ce56b8 R08: 0000000000000001 R09: 00007fd857ce4d70 R10: 00007fd857ce4c27 R11: 0000000000000246 R12: 0000000000000008 R13: 0000000000000000 R14: 0000000000000000 R15: 00007fd857ce4f60 INFO: task systemd-udevd:10046 blocked for more than 140 seconds. Not tainted 4.14.281-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D28712 10046 4626 0x00000300 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 lo_open+0x19/0xb0 drivers/block/loop.c:1634 __blkdev_get+0xa8c/0x1090 fs/block_dev.c:1537 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fae58e43840 RSP: 002b:00007ffd109361c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000055d9c86b8430 RCX: 00007fae58e43840 RDX: 000055d9c7e52fe3 RSI: 0000000000080000 RDI: 000055d9c86b5d50 RBP: 0000000000000001 R08: 000055d9c7e52670 R09: 0000000000000110 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 000055d9c86c46e0 R15: 00000000ffffffff INFO: task syz-executor.2:10065 blocked for more than 140 seconds. Not tainted 4.14.281-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D25416 10065 7975 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 loop_control_ioctl+0x181/0x3f0 drivers/block/loop.c:2007 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f5f21ee7109 RSP: 002b:00007f5f2081a168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f5f21ffa100 RCX: 00007f5f21ee7109 RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000003 RBP: 00007f5f21f4108d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdca1eee4f R14: 00007f5f2081a300 R15: 0000000000022000 INFO: task systemd-udevd:10061 blocked for more than 140 seconds. Not tainted 4.14.281-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D28712 10061 4626 0x00000300 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 blkdev_put+0x27/0x4c0 fs/block_dev.c:1826 blkdev_close+0x86/0xb0 fs/block_dev.c:1875 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fae58e43270 RSP: 002b:00007ffd1093a9e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007fae58e43270 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007 RBP: 00007fae59cfd710 R08: 000055d9c86c3b90 R09: 000055d9c86c3900 R10: 00007fae59cfd8c0 R11: 0000000000000246 R12: 0000000000000000 R13: 000055d9c86c3c80 R14: 0000000000000003 R15: 000000000000000e INFO: task syz-executor.5:10070 blocked for more than 140 seconds. Not tainted 4.14.281-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29248 10070 7972 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f4283d5b024 RSP: 002b:00007f428271ceb0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f4283df1a20 RCX: 00007f4283d5b024 RDX: 0000000000000002 RSI: 00007f428271cfe0 RDI: 00000000ffffff9c RBP: 00007f428271cfe0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 0000000000000003 R14: 0000000020000258 R15: 0000000000000001 INFO: task systemd-udevd:10069 blocked for more than 140 seconds. Not tainted 4.14.281-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D28912 10069 4626 0x00000300 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fae58e43840 RSP: 002b:00007ffd1093aff8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000055d9c86b5de0 RCX: 00007fae58e43840 RDX: 000055d9c7e52fe3 RSI: 00000000000a0800 RDI: 000055d9c86c7c90 RBP: 00007ffd1093b170 R08: 000055d9c7e52670 R09: 0000000000000010 R10: 000055d9c7e52d0c R11: 0000000000000246 R12: 00007ffd1093b0c0 R13: 000055d9c86c6a10 R14: 0000000000000003 R15: 000000000000000e Showing all locks held in the system: 1 lock held by khungtaskd/1533: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 2 locks held by systemd-udevd/4626: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 #1: (loop_index_mutex){+.+.}, at: [] lo_open+0x19/0xb0 drivers/block/loop.c:1634 1 lock held by in:imklog/7739: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0x1fb/0x2b0 fs/file.c:819 1 lock held by syz-executor.3/7970: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 2 locks held by syz-executor.4/7976: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_put+0xd8/0x800 fs/block_dev.c:1790 #1: (loop_index_mutex){+.+.}, at: [] lo_release+0x1b/0x190 drivers/block/loop.c:1677 2 locks held by systemd-udevd/10040: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 #1: (loop_index_mutex){+.+.}, at: [] lo_open+0x19/0xb0 drivers/block/loop.c:1634 2 locks held by syz-executor.0/10047: #0: (&lo->lo_ctl_mutex/1){+.+.}, at: [] lo_ioctl+0x87/0x1cd0 drivers/block/loop.c:1414 #1: (&bdev->bd_mutex){+.+.}, at: [] blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 2 locks held by systemd-udevd/10046: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 #1: (loop_index_mutex){+.+.}, at: [] lo_open+0x19/0xb0 drivers/block/loop.c:1634 2 locks held by syz-executor.2/10065: #0: (loop_index_mutex){+.+.}, at: [] loop_control_ioctl+0x67/0x3f0 drivers/block/loop.c:1993 #1: (&lo->lo_ctl_mutex){+.+.}, at: [] loop_control_ioctl+0x181/0x3f0 drivers/block/loop.c:2007 1 lock held by systemd-udevd/10061: #0: (&bdev->bd_mutex){+.+.}, at: [] blkdev_put+0x27/0x4c0 fs/block_dev.c:1826 1 lock held by syz-executor.5/10070: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 1 lock held by systemd-udevd/10069: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 2 locks held by syz-executor.1/10072: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 #1: (loop_index_mutex){+.+.}, at: [] lo_open+0x19/0xb0 drivers/block/loop.c:1634 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1533 Comm: khungtaskd Not tainted 4.14.281-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7742 Comm: rs:main Q:Reg Not tainted 4.14.281-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff88809f650340 task.stack: ffff88809ed18000 RIP: 0010:kasan_kmalloc+0x84/0x160 mm/kasan/kasan.c:550 RSP: 0018:ffff88809ed1f548 EFLAGS: 00000246 RAX: ffffed100b91e79c RBX: ffff88805c8f3ce0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 00000000000000fc RDI: ffffed100b91e79c RBP: ffff88805c8f3c78 R08: ffffed100b91e78f R09: ffffed100b91e79c R10: 0000000000000000 R11: ffff88809f650340 R12: 0000000001408040 R13: 0000000000000000 R14: ffff88823f830dc0 R15: 0000000000000068 FS: 00007fa84cc30700(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcbf84ce008 CR3: 00000000a1d4a000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000003b DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kmem_cache_alloc+0x124/0x3c0 mm/slab.c:3552 kmem_cache_zalloc include/linux/slab.h:651 [inline] alloc_buffer_head+0x20/0x110 fs/buffer.c:3429 alloc_page_buffers+0xb3/0x1f0 fs/buffer.c:874 create_empty_buffers+0x36/0x450 fs/buffer.c:1590 create_page_buffers+0x14d/0x1c0 fs/buffer.c:1707 __block_write_begin_int+0x176/0x1090 fs/buffer.c:2017 ext4_da_write_begin+0x402/0xe70 fs/ext4/inode.c:3141 generic_perform_write+0x1c9/0x420 mm/filemap.c:3055 __generic_file_write_iter+0x227/0x590 mm/filemap.c:3180 ext4_file_write_iter+0x276/0xd20 fs/ext4/file.c:270 call_write_iter include/linux/fs.h:1780 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x44c/0x630 fs/read_write.c:482 vfs_write+0x17f/0x4d0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fa84f6741cd RSP: 002b:00007fa84cc2f590 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fa844006090 RCX: 00007fa84f6741cd RDX: 00000000000004a6 RSI: 00007fa844006090 RDI: 0000000000000008 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007fa844005df0 R13: 00007fa84cc2f5b0 R14: 0000561c99387440 R15: 00000000000004a6 Code: d9 48 c1 e9 03 be fc 00 00 00 49 29 c5 48 b8 00 00 00 00 00 fc ff df 4a 8d 14 2b 48 8d 3c 01 48 c1 ea 03 48 29 ca e8 1c 30 82 05 <41> f6 46 23 08 75 19 48 81 c4 20 02 00 00 5b 5d 41 5c 41 5d 41 ---------------- Code disassembly (best guess): 0: d9 48 c1 (bad) -0x3f(%rax) 3: e9 03 be fc 00 jmpq 0xfcbe0b 8: 00 00 add %al,(%rax) a: 49 29 c5 sub %rax,%r13 d: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 14: fc ff df 17: 4a 8d 14 2b lea (%rbx,%r13,1),%rdx 1b: 48 8d 3c 01 lea (%rcx,%rax,1),%rdi 1f: 48 c1 ea 03 shr $0x3,%rdx 23: 48 29 ca sub %rcx,%rdx 26: e8 1c 30 82 05 callq 0x5823047 * 2b: 41 f6 46 23 08 testb $0x8,0x23(%r14) <-- trapping instruction 30: 75 19 jne 0x4b 32: 48 81 c4 20 02 00 00 add $0x220,%rsp 39: 5b pop %rbx 3a: 5d pop %rbp 3b: 41 5c pop %r12 3d: 41 5d pop %r13 3f: 41 rex.B