audit: type=1800 audit(1611431897.771:175): pid=26678 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.5" name="file0" dev="sda1" ino=17715 res=0 audit: type=1800 audit(1611431897.821:176): pid=26691 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.5" name="file0" dev="sda1" ino=17715 res=0 Process accounting resumed INFO: task syz-executor.3:26638 blocked for more than 140 seconds. Not tainted 4.14.217-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D29272 26638 8020 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:588 [inline] rwsem_down_write_failed+0x343/0x6d0 kernel/locking/rwsem-xadd.c:617 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:105 __down_write arch/x86/include/asm/rwsem.h:126 [inline] down_write+0x4f/0x90 kernel/locking/rwsem.c:56 grab_super+0x55/0x140 fs/super.c:373 sget_userns+0x2b1/0xc10 fs/super.c:504 sget+0xd1/0x110 fs/super.c:572 mount_bdev+0xcd/0x360 fs/super.c:1107 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45e219 RSP: 002b:00007f1bf5e84c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e219 RDX: 00000000200000c0 RSI: 0000000020000140 RDI: 0000000020000080 RBP: 000000000119bfd0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffffd5531ff R14: 00007f1bf5e859c0 R15: 000000000119bf8c Showing all locks held in the system: 1 lock held by khungtaskd/1531: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 2 locks held by syz-executor.3/26638: #0: (&bdev->bd_fsfreeze_mutex){+.+.}, at: [] mount_bdev+0x71/0x360 fs/super.c:1101 #1: (&type->s_umount_key#85){+.+.}, at: [] grab_super+0x55/0x140 fs/super.c:373 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1531 Comm: khungtaskd Not tainted 4.14.217-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: 26612 Comm: syz-executor.3 Not tainted 4.14.217-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff888068eca340 task.stack: ffff888238310000 RIP: 0010:__read_once_size include/linux/compiler.h:183 [inline] RIP: 0010:radix_tree_load_root lib/radix-tree.c:602 [inline] RIP: 0010:__radix_tree_lookup+0x58/0x2e0 lib/radix-tree.c:1040 RSP: 0018:ffff888238317818 EFLAGS: 00000246 RAX: ffffed1012068977 RBX: 1ffff11047062f12 RCX: ffff8882383178b0 RDX: 0000000000000000 RSI: 0000000000000020 RDI: ffff888090344bb0 RBP: 0000000000000020 R08: 0000000000000000 R09: 0000000000020012 R10: ffff888068ecabf0 R11: ffff888068eca340 R12: 0000000000000040 R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000020 FS: 00007f1bf5e85700(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa232b3a008 CR3: 000000023831e000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: radix_tree_lookup_slot+0x60/0xa0 lib/radix-tree.c:1079 find_get_entry+0x8b/0x630 mm/filemap.c:1355 pagecache_get_page+0x53/0xab0 mm/filemap.c:1465 find_get_page_flags include/linux/pagemap.h:282 [inline] __find_get_block_slow fs/buffer.c:214 [inline] __find_get_block+0x4cc/0xc40 fs/buffer.c:1357 __getblk_slow+0x127/0x7a0 fs/buffer.c:1100 __getblk_gfp fs/buffer.c:1383 [inline] __bread_gfp+0x206/0x2e0 fs/buffer.c:1428 sb_bread include/linux/buffer_head.h:309 [inline] isofs_fill_super+0x959/0x23f0 fs/isofs/inode.c:678 mount_bdev+0x2b3/0x360 fs/super.c:1134 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45e219 RSP: 002b:00007f1bf5e84c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e219 RDX: 00000000200000c0 RSI: 0000000020000140 RDI: 0000000020000080 RBP: 000000000119bfd0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffffd5531ff R14: 00007f1bf5e859c0 R15: 000000000119bf8c Code: 48 89 7c 24 08 48 89 34 24 48 89 54 24 18 48 89 4c 24 20 48 89 44 24 10 41 bc 40 00 00 00 e8 10 c9 59 fa 48 8b 44 24 10 80 38 00 <0f> 85 3b 02 00 00 48 8b 44 24 08 48 8b 58 08 48 89 d8 83 e0 03