INFO: task syz-executor412:8108 blocked for more than 140 seconds. Not tainted 4.19.206-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor412 D27344 8108 8106 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 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x3aa/0x760 kernel/locking/rwsem-xadd.c:618 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x4f/0x90 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:748 [inline] fuse_reverse_inval_entry+0xaa/0x660 fs/fuse/dir.c:987 fuse_notify_inval_entry fs/fuse/dev.c:1535 [inline] fuse_notify fs/fuse/dev.c:1810 [inline] fuse_dev_do_write+0x251c/0x2bc0 fs/fuse/dev.c:1894 fuse_dev_write+0x153/0x1e0 fs/fuse/dev.c:1978 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x51b/0x770 fs/read_write.c:487 vfs_write+0x1f3/0x540 fs/read_write.c:549 ksys_write+0x12b/0x2a0 fs/read_write.c:599 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x44af59 Code: Bad RIP value. RSP: 002b:00007f5e3c411208 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000004cb4e8 RCX: 000000000044af59 RDX: 0000000000000029 RSI: 00000000200043c0 RDI: 0000000000000003 RBP: 00000000004cb4e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004cb4ec R13: 00007ffdf5d1898f R14: 00007f5e3c411300 R15: 0000000000022000 INFO: task syz-executor412:8113 blocked for more than 140 seconds. Not tainted 4.19.206-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor412 D28488 8113 8106 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 request_wait_answer+0x3dc/0x750 fs/fuse/dev.c:485 __fuse_request_send+0x123/0x1c0 fs/fuse/dev.c:505 fuse_simple_request+0x2e6/0x820 fs/fuse/dev.c:576 fuse_lookup_name+0x24c/0x5c0 fs/fuse/dir.c:330 fuse_lookup+0xdf/0x410 fs/fuse/dir.c:368 __lookup_hash+0x117/0x180 fs/namei.c:1547 filename_create+0x186/0x490 fs/namei.c:3639 user_path_create fs/namei.c:3696 [inline] do_mkdirat+0xa0/0x2d0 fs/namei.c:3834 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x44af59 Code: Bad RIP value. RSP: 002b:00007f5e3c3f0208 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00000000004cb4f8 RCX: 000000000044af59 RDX: 0000000000000000 RSI: 0000000020004380 RDI: 00000000ffffff9c RBP: 00000000004cb4f0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004cb4fc R13: 00007ffdf5d1898f R14: 00007f5e3c3f0300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1490: #0: 000000006da82cfa (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7808: #0: 00000000965495d9 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 2 locks held by syz-executor412/8108: #0: 00000000181afe93 (&fc->killsb){.+.+}, at: fuse_notify_inval_entry fs/fuse/dev.c:1532 [inline] #0: 00000000181afe93 (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1810 [inline] #0: 00000000181afe93 (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x24c7/0x2bc0 fs/fuse/dev.c:1894 #1: 000000009f9ab0b6 (&type->i_mutex_dir_key#8){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #1: 000000009f9ab0b6 (&type->i_mutex_dir_key#8){+.+.}, at: fuse_reverse_inval_entry+0xaa/0x660 fs/fuse/dir.c:987 3 locks held by syz-executor412/8113: #0: 00000000e62e60c8 (sb_writers#11){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline] #0: 00000000e62e60c8 (sb_writers#11){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360 #1: 000000009f9ab0b6 (&type->i_mutex_dir_key#7/1){+.+.}, at: inode_lock_nested include/linux/fs.h:783 [inline] #1: 000000009f9ab0b6 (&type->i_mutex_dir_key#7/1){+.+.}, at: filename_create+0x15a/0x490 fs/namei.c:3638 #2: 000000004de6e4a2 (&fi->mutex){+.+.}, at: fuse_lock_inode+0xaf/0xe0 fs/fuse/inode.c:365 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1490 Comm: khungtaskd Not tainted 4.19.206-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 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60