bisecting fixing commit since 5b7a52cd2eef952cee8a72512ef370bcdef46636 building syzkaller on 94942294277bf7550b12322d282159551521258b testing commit 5b7a52cd2eef952cee8a72512ef370bcdef46636 with gcc (GCC) 8.4.1 20210217 kernel signature: a94bf93c6894213520636fbf8c92717771d6f78541dccdf73cb4c9c78a781987 run #0: crashed: possible deadlock in __get_super run #1: crashed: possible deadlock in blkdev_put run #2: crashed: possible deadlock in __get_super run #3: crashed: possible deadlock in __get_super run #4: crashed: possible deadlock in __get_super run #5: crashed: possible deadlock in __get_super run #6: crashed: possible deadlock in __get_super run #7: crashed: possible deadlock in __get_super run #8: crashed: possible deadlock in __get_super run #9: crashed: possible deadlock in __get_super run #10: crashed: possible deadlock in __get_super run #11: crashed: possible deadlock in __get_super run #12: crashed: INFO: task hung in blkdev_put run #13: crashed: INFO: task hung in blkdev_put run #14: crashed: INFO: task hung in blkdev_put run #15: crashed: INFO: task hung in blkdev_put run #16: crashed: INFO: task hung in blkdev_put run #17: crashed: INFO: task hung in blkdev_put run #18: crashed: INFO: task hung in blkdev_put run #19: crashed: INFO: task hung in __get_super testing current HEAD cf256fbcbe347b7d0ff58fe2dfa382a156bd3694 testing commit cf256fbcbe347b7d0ff58fe2dfa382a156bd3694 with gcc (GCC) 8.4.1 20210217 kernel signature: 0d8c474d26119ca9df2f1b10c8cbe09e977bf248b44f8446b42d45d3f0ebc773 run #0: crashed: INFO: task hung in blkdev_put run #1: crashed: INFO: task hung in blkdev_put run #2: crashed: INFO: task hung in __get_super run #3: crashed: INFO: task hung in __get_super run #4: crashed: INFO: task hung in blkdev_put run #5: crashed: INFO: task hung in __blkdev_get run #6: crashed: INFO: task hung in __get_super run #7: crashed: INFO: task hung in blkdev_put run #8: crashed: INFO: task hung in blkdev_put run #9: crashed: INFO: task hung in __get_super revisions tested: 2, total time: 31m38.790438625s (build: 17m2.975808226s, test: 14m3.340434823s) the crash still happens on HEAD commit msg: Linux 4.14.231 crash: INFO: task hung in __get_super Bluetooth: hci2 command 0x0406 tx timeout Bluetooth: hci0 command 0x0406 tx timeout Bluetooth: hci3 command 0x0406 tx timeout Bluetooth: hci4 command 0x0406 tx timeout Bluetooth: hci5 command 0x0406 tx timeout INFO: task syz-executor.2:9181 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D27920 9181 7679 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x1fb/0x390 kernel/locking/rwsem-xadd.c:309 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:66 [inline] down_read+0x49/0xb0 kernel/locking/rwsem.c:26 __get_super.part.2+0x190/0x260 fs/super.c:678 __get_super include/linux/spinlock.h:317 [inline] get_super+0x23/0x30 fs/super.c:707 fsync_bdev+0x13/0xb0 fs/block_dev.c:495 invalidate_partition+0x1f/0x40 block/genhd.c:1509 drop_partitions block/partition-generic.c:442 [inline] rescan_partitions+0xac/0x8c0 block/partition-generic.c:515 __blkdev_reread_part+0x12a/0x190 block/ioctl.c:173 blkdev_reread_part+0x20/0x40 block/ioctl.c:193 loop_reread_partitions+0x5d/0x70 drivers/block/loop.c:624 loop_set_status+0xb04/0x1070 drivers/block/loop.c:1193 loop_set_status_old+0x174/0x1c0 drivers/block/loop.c:1301 lo_ioctl+0x8c7/0x1c30 drivers/block/loop.c:1431 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x7c0/0x1760 block/ioctl.c:594 block_ioctl+0xd7/0x130 fs/block_dev.c:1893 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x180/0xfb0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x74/0x80 fs/ioctl.c:692 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x465849 RSP: 002b:00007fa03b979188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000055c050 RCX: 0000000000465849 RDX: 0000000020000280 RSI: 0000000000004c02 RDI: 0000000000000003 RBP: 00000000004af675 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055c050 R13: 00007ffcf186b20f R14: 00007fa03b979300 R15: 0000000000022000 INFO: task syz-executor.3:9154 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28344 9154 7682 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 blkdev_put+0x25/0x470 fs/block_dev.c:1826 blkdev_close+0x88/0xd0 fs/block_dev.c:1875 __fput+0x232/0x740 fs/file_table.c:210 ____fput+0x9/0x10 fs/file_table.c:244 task_work_run+0xe5/0x170 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x14a/0x190 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+0x416/0x5b0 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418b5b RSP: 002b:00007fff5a18a070 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000418b5b RDX: 00000000000003e7 RSI: 0000001b33a2012c RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000001b33a20134 R10: 000e7cd536b8945b R11: 0000000000000293 R12: 000000000055c980 R13: 000000000000ba3e R14: 000000000055c980 R15: 000000000055bfa8 INFO: task syz-executor.0:9155 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28344 9155 7680 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 blkdev_put+0x25/0x470 fs/block_dev.c:1826 blkdev_close+0x88/0xd0 fs/block_dev.c:1875 __fput+0x232/0x740 fs/file_table.c:210 ____fput+0x9/0x10 fs/file_table.c:244 task_work_run+0xe5/0x170 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x14a/0x190 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+0x416/0x5b0 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418b5b RSP: 002b:00007ffdc0d2c090 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000418b5b RDX: 00000000000003e7 RSI: 0000001b3392012c RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000001b33920134 R10: 000e7de992b284eb R11: 0000000000000293 R12: 000000000055c980 R13: 000000000000ba3e R14: 000000000055c980 R15: 000000000055bfa8 INFO: task syz-executor.0:9157 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D26712 9157 7680 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 blkdev_put+0x25/0x470 fs/block_dev.c:1826 release_journal_dev fs/reiserfs/journal.c:2598 [inline] free_journal_ram+0x340/0x4c0 fs/reiserfs/journal.c:1903 do_journal_release fs/reiserfs/journal.c:1969 [inline] journal_release_error+0x74/0xa0 fs/reiserfs/journal.c:1987 reiserfs_fill_super+0x1323/0x26f0 fs/reiserfs/super.c:2228 mount_bdev+0x26f/0x330 fs/super.c:1134 get_super_block+0x10/0x20 fs/reiserfs/super.c:2609 mount_fs+0x7f/0x270 fs/super.c:1237 vfs_kern_mount.part.9+0x58/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x352/0x2af0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xb1/0xd0 fs/namespace.c:3072 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x466d6a RSP: 002b:00007f1e70d85fa8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 0000000000466d6a RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f1e70d86000 RBP: 00007f1e70d86040 R08: 00007f1e70d86040 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000000 R13: 0000000020000100 R14: 00007f1e70d86000 R15: 0000000020011100 INFO: task syz-executor.5:9249 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28904 9249 7686 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 __blkdev_get+0x185/0xff0 fs/block_dev.c:1455 blkdev_get+0x265/0x890 fs/block_dev.c:1611 blkdev_open+0x19f/0x200 fs/block_dev.c:1772 do_dentry_open+0x3e4/0xde0 fs/open.c:777 vfs_open+0xfc/0x240 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0xb6f/0x2760 fs/namei.c:3569 do_filp_open+0x16b/0x220 fs/namei.c:3603 do_sys_open+0x1d0/0x350 fs/open.c:1081 SYSC_openat fs/open.c:1108 [inline] SyS_openat+0xf/0x20 fs/open.c:1102 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418e34 RSP: 002b:00007f7819d47cc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000418e34 RDX: 0000000000000000 RSI: 00007f7819d47d60 RDI: 00000000ffffff9c RBP: 00007f7819d47d60 R08: 0000000000000000 R09: 0023706f6f6c2f76 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fff6223ebaf R14: 00007f7819d48300 R15: 0000000000022000 INFO: task syz-executor.5:9267 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28776 9267 7686 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 __blkdev_get+0x185/0xff0 fs/block_dev.c:1455 blkdev_get+0x265/0x890 fs/block_dev.c:1611 blkdev_open+0x19f/0x200 fs/block_dev.c:1772 do_dentry_open+0x3e4/0xde0 fs/open.c:777 vfs_open+0xfc/0x240 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0xb6f/0x2760 fs/namei.c:3569 do_filp_open+0x16b/0x220 fs/namei.c:3603 do_sys_open+0x1d0/0x350 fs/open.c:1081 SYSC_openat fs/open.c:1108 [inline] SyS_openat+0xf/0x20 fs/open.c:1102 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418e34 RSP: 002b:00007f7819d05cc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000418e34 RDX: 0000000000000000 RSI: 00007f7819d05d60 RDI: 00000000ffffff9c RBP: 00007f7819d05d60 R08: 0000000000000000 R09: 0023706f6f6c2f76 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fff6223ebaf R14: 00007f7819d06300 R15: 0000000000022000 INFO: task syz-executor.1:9250 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28904 9250 7687 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 __blkdev_get+0x185/0xff0 fs/block_dev.c:1455 blkdev_get+0x265/0x890 fs/block_dev.c:1611 blkdev_open+0x19f/0x200 fs/block_dev.c:1772 do_dentry_open+0x3e4/0xde0 fs/open.c:777 vfs_open+0xfc/0x240 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0xb6f/0x2760 fs/namei.c:3569 do_filp_open+0x16b/0x220 fs/namei.c:3603 do_sys_open+0x1d0/0x350 fs/open.c:1081 SYSC_openat fs/open.c:1108 [inline] SyS_openat+0xf/0x20 fs/open.c:1102 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418e34 RSP: 002b:00007f163c817cc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000418e34 RDX: 0000000000000000 RSI: 00007f163c817d60 RDI: 00000000ffffff9c RBP: 00007f163c817d60 R08: 0000000000000000 R09: 0023706f6f6c2f76 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fffc4cdeeaf R14: 00007f163c818300 R15: 0000000000022000 INFO: task syz-executor.1:9273 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28904 9273 7687 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 __blkdev_get+0x185/0xff0 fs/block_dev.c:1455 blkdev_get+0x265/0x890 fs/block_dev.c:1611 blkdev_open+0x19f/0x200 fs/block_dev.c:1772 do_dentry_open+0x3e4/0xde0 fs/open.c:777 vfs_open+0xfc/0x240 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0xb6f/0x2760 fs/namei.c:3569 do_filp_open+0x16b/0x220 fs/namei.c:3603 do_sys_open+0x1d0/0x350 fs/open.c:1081 SYSC_openat fs/open.c:1108 [inline] SyS_openat+0xf/0x20 fs/open.c:1102 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418e34 RSP: 002b:00007f163c7d5cc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000418e34 RDX: 0000000000000000 RSI: 00007f163c7d5d60 RDI: 00000000ffffff9c RBP: 00007f163c7d5d60 R08: 0000000000000000 R09: 0023706f6f6c2f76 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fffc4cdeeaf R14: 00007f163c7d6300 R15: 0000000000022000 INFO: task syz-executor.4:9290 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28840 9290 7684 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 __blkdev_get+0x185/0xff0 fs/block_dev.c:1455 blkdev_get+0x265/0x890 fs/block_dev.c:1611 blkdev_open+0x19f/0x200 fs/block_dev.c:1772 do_dentry_open+0x3e4/0xde0 fs/open.c:777 vfs_open+0xfc/0x240 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0xb6f/0x2760 fs/namei.c:3569 do_filp_open+0x16b/0x220 fs/namei.c:3603 do_sys_open+0x1d0/0x350 fs/open.c:1081 SYSC_openat fs/open.c:1108 [inline] SyS_openat+0xf/0x20 fs/open.c:1102 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418e34 RSP: 002b:00007fbdc0b95cc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000418e34 RDX: 0000000000000000 RSI: 00007fbdc0b95d60 RDI: 00000000ffffff9c RBP: 00007fbdc0b95d60 R08: 0000000000000000 R09: 0023706f6f6c2f76 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007ffe19361c1f R14: 00007fbdc0b96300 R15: 0000000000022000 INFO: task syz-executor.4:9299 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28904 9299 7684 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 __blkdev_get+0x185/0xff0 fs/block_dev.c:1455 blkdev_get+0x265/0x890 fs/block_dev.c:1611 blkdev_open+0x19f/0x200 fs/block_dev.c:1772 do_dentry_open+0x3e4/0xde0 fs/open.c:777 vfs_open+0xfc/0x240 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0xb6f/0x2760 fs/namei.c:3569 do_filp_open+0x16b/0x220 fs/namei.c:3603 do_sys_open+0x1d0/0x350 fs/open.c:1081 SYSC_openat fs/open.c:1108 [inline] SyS_openat+0xf/0x20 fs/open.c:1102 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418e34 RSP: 002b:00007fbdc0b53cc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000418e34 RDX: 0000000000000000 RSI: 00007fbdc0b53d60 RDI: 00000000ffffff9c RBP: 00007fbdc0b53d60 R08: 0000000000000000 R09: 0023706f6f6c2f76 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007ffe19361c1f R14: 00007fbdc0b54300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1531: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4548 1 lock held by in:imklog/7145: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0x8e/0xc0 fs/file.c:769 3 locks held by syz-executor.2/9181: #0: (&lo->lo_ctl_mutex/1){+.+.}, at: [] lo_ioctl+0x8a/0x1c30 drivers/block/loop.c:1414 #1: (&bdev->bd_mutex){+.+.}, at: [] blkdev_reread_part+0x18/0x40 block/ioctl.c:192 #2: (&type->s_umount_key#48){.+.+}, at: [] __get_super.part.2+0x190/0x260 fs/super.c:678 1 lock held by syz-executor.3/9154: #0: (&bdev->bd_mutex){+.+.}, at: [] blkdev_put+0x25/0x470 fs/block_dev.c:1826 1 lock held by syz-executor.0/9155: #0: (&bdev->bd_mutex){+.+.}, at: [] blkdev_put+0x25/0x470 fs/block_dev.c:1826 2 locks held by syz-executor.0/9157: #0: (&type->s_umount_key#22/1){+.+.}, at: [] alloc_super fs/super.c:251 [inline] #0: (&type->s_umount_key#22/1){+.+.}, at: [] sget_userns+0x429/0xb40 fs/super.c:516 #1: (&bdev->bd_mutex){+.+.}, at: [] blkdev_put+0x25/0x470 fs/block_dev.c:1826 1 lock held by syz-executor.5/9249: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x185/0xff0 fs/block_dev.c:1455 1 lock held by syz-executor.5/9267: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x185/0xff0 fs/block_dev.c:1455 1 lock held by syz-executor.1/9250: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x185/0xff0 fs/block_dev.c:1455 1 lock held by syz-executor.1/9273: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x185/0xff0 fs/block_dev.c:1455 1 lock held by syz-executor.4/9290: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x185/0xff0 fs/block_dev.c:1455 1 lock held by syz-executor.4/9299: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x185/0xff0 fs/block_dev.c:1455 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1531 Comm: khungtaskd Not tainted 4.14.231-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+0x14b/0x1e7 lib/dump_stack.c:58 nmi_cpu_backtrace.cold.0+0x3c/0x78 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xf6/0x120 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x51b/0xa70 kernel/hung_task.c:274 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: kworker/u4:2 Not tainted 4.14.231-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: phy8 ieee80211_iface_work task: ffff8881f4e70080 task.stack: ffff8881f4e78000 RIP: 0010:___might_sleep+0x1/0x2b0 kernel/sched/core.c:5996 RSP: 0018:ffff8881f4e7fa10 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8881f4e70080 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 00000000000002eb RDI: ffffffff8789a840 RBP: ffff8881f4e7fa50 R08: ffffffff86c79212 R09: 0000000000000000 R10: ffff8881f4e7fbf8 R11: 0000000000000000 R12: ffffffff8789a840 R13: 00000000000002eb R14: 0000000000000000 R15: ffff8881db09a308 FS: 0000000000000000(0000) GS:ffff8881f6400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f50f17d5000 CR3: 0000000008e6a001 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __mutex_lock_common kernel/locking/mutex.c:747 [inline] __mutex_lock+0xbf/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 ieee80211_ibss_sta_expire net/mac80211/ibss.c:1261 [inline] ieee80211_sta_merge_ibss net/mac80211/ibss.c:1297 [inline] ieee80211_ibss_work+0x3b2/0xd80 net/mac80211/ibss.c:1703 ieee80211_iface_work+0x4a6/0x690 net/mac80211/iface.c:1383 process_one_work+0x74f/0x1620 kernel/workqueue.c:2116 worker_thread+0xcc/0xee0 kernel/workqueue.c:2250 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Code: dc 05 eb dc 0f 0b e8 4f 24 45 00 eb bd e8 48 24 45 00 e9 2f ff ff ff e8 1e 24 45 00 e9 63 ff ff ff 66 0f 1f 84 00 00 00 00 00 55 <48> 89 e5 41 57 41 56 41 89 f6 41 55 49 89 fd 41 54 41 89 d4 53