INFO: task syz-executor.5:19944 can't die for more than 143 seconds. task:syz-executor.5 state:D stack:28976 pid:19944 ppid: 6899 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4965 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6246 schedule+0xd2/0x260 kernel/sched/core.c:6319 rwsem_down_write_slowpath+0x7b9/0x11d0 kernel/locking/rwsem.c:1107 __down_write_common kernel/locking/rwsem.c:1262 [inline] __down_write_common kernel/locking/rwsem.c:1259 [inline] __down_write kernel/locking/rwsem.c:1271 [inline] down_write+0x135/0x150 kernel/locking/rwsem.c:1518 prealloc_memcg_shrinker mm/vmscan.c:359 [inline] prealloc_shrinker+0x13d/0x7c0 mm/vmscan.c:620 alloc_super+0x84c/0xac0 fs/super.c:270 sget_fc+0x13e/0x7c0 fs/super.c:531 vfs_get_super fs/super.c:1135 [inline] get_tree_nodev+0x24/0x1d0 fs/super.c:1170 vfs_get_tree+0x89/0x2f0 fs/super.c:1498 do_new_mount fs/namespace.c:2988 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3318 do_mount fs/namespace.c:3331 [inline] __do_sys_mount fs/namespace.c:3539 [inline] __se_sys_mount fs/namespace.c:3516 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3516 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f055dcd8a39 RSP: 002b:00007f055b1eb188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f055dddc1a0 RCX: 00007f055dcd8a39 RDX: 0000000020000140 RSI: 0000000020000080 RDI: 0000000000000000 RBP: 00007f055dd32c5f R08: 0000000020000440 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd572e773f R14: 00007f055b1eb300 R15: 0000000000022000 INFO: task syz-executor.5:19944 blocked for more than 143 seconds. Not tainted 5.15.0-rc5-next-20211013-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:28976 pid:19944 ppid: 6899 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4965 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6246 schedule+0xd2/0x260 kernel/sched/core.c:6319 rwsem_down_write_slowpath+0x7b9/0x11d0 kernel/locking/rwsem.c:1107 __down_write_common kernel/locking/rwsem.c:1262 [inline] __down_write_common kernel/locking/rwsem.c:1259 [inline] __down_write kernel/locking/rwsem.c:1271 [inline] down_write+0x135/0x150 kernel/locking/rwsem.c:1518 prealloc_memcg_shrinker mm/vmscan.c:359 [inline] prealloc_shrinker+0x13d/0x7c0 mm/vmscan.c:620 alloc_super+0x84c/0xac0 fs/super.c:270 sget_fc+0x13e/0x7c0 fs/super.c:531 vfs_get_super fs/super.c:1135 [inline] get_tree_nodev+0x24/0x1d0 fs/super.c:1170 vfs_get_tree+0x89/0x2f0 fs/super.c:1498 do_new_mount fs/namespace.c:2988 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3318 do_mount fs/namespace.c:3331 [inline] __do_sys_mount fs/namespace.c:3539 [inline] __se_sys_mount fs/namespace.c:3516 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3516 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f055dcd8a39 RSP: 002b:00007f055b1eb188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f055dddc1a0 RCX: 00007f055dcd8a39 RDX: 0000000020000140 RSI: 0000000020000080 RDI: 0000000000000000 RBP: 00007f055dd32c5f R08: 0000000020000440 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd572e773f R14: 00007f055b1eb300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8bb82ea0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 3 locks held by khugepaged/33: 1 lock held by in:imklog/6235: 3 locks held by syz-executor.3/19072: 2 locks held by syz-executor.5/19944: #0: ffff88808f5f60e0 (&type->s_umount_key#70/1){+.+.}-{3:3}, at: alloc_super+0x1dd/0xac0 fs/super.c:229 #1: ffffffff8bc6c2f0 (shrinker_rwsem){++++}-{3:3}, at: prealloc_memcg_shrinker mm/vmscan.c:359 [inline] #1: ffffffff8bc6c2f0 (shrinker_rwsem){++++}-{3:3}, at: prealloc_shrinker+0x13d/0x7c0 mm/vmscan.c:620 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.0-rc5-next-20211013-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:254 [inline] watchdog+0xcb7/0xed0 kernel/hung_task.c:339 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6525 Comm: syz-fuzzer Not tainted 5.15.0-rc5-next-20211013-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_wait_context kernel/locking/lockdep.c:4705 [inline] RIP: 0010:__lock_acquire+0x4c7/0x54a0 kernel/locking/lockdep.c:4977 Code: 0f 84 af 02 00 00 49 8d 7c 24 21 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 <84> c0 0f 85 dc 38 00 00 41 0f b6 54 24 21 84 d2 0f 88 c2 0b 00 00 RSP: 0018:ffffc90001a4f8a0 EFLAGS: 00000097 RAX: 0000000000000000 RBX: ffffffff8bb82ea0 RCX: ffffffff815c292c RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88801746c4b1 RBP: ffffffff8ff44c20 R08: 0000000000000000 R09: ffffffff8ff42a07 R10: fffffbfff1fe8540 R11: 0000000000000000 R12: ffff88801746c490 R13: ffff88801746ba00 R14: 0000000000020000 R15: 0000000000000002 FS: 000000c00002e090(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c004abf900 CR3: 000000001d11c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:694 [inline] select_task_rq_fair+0x29c/0x3b50 kernel/sched/fair.c:6903 select_task_rq kernel/sched/core.c:3400 [inline] try_to_wake_up+0x38b/0x15a0 kernel/sched/core.c:4082 wake_up_process kernel/sched/core.c:4181 [inline] wake_up_q+0x7e/0xf0 kernel/sched/core.c:953 futex_wake+0x3e9/0x490 kernel/futex/waitwake.c:184 do_futex+0x25b/0x390 kernel/futex/syscalls.c:127 __do_sys_futex kernel/futex/syscalls.c:199 [inline] __se_sys_futex kernel/futex/syscalls.c:180 [inline] __x64_sys_futex+0x1b0/0x4a0 kernel/futex/syscalls.c:180 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x46e203 Code: 24 20 c3 cc cc cc cc 48 8b 7c 24 08 8b 74 24 10 8b 54 24 14 4c 8b 54 24 18 4c 8b 44 24 20 44 8b 4c 24 28 b8 ca 00 00 00 0f 05 <89> 44 24 30 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc RSP: 002b:000000c00003de70 EFLAGS: 00000206 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 000000000046e203 RDX: 0000000000000001 RSI: 0000000000000081 RDI: 000000c00002e548 RBP: 000000c00003dec0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 000000000043b6e0 R13: 0000000000000000 R14: 0000000000c53c48 R15: 0000000000000000 ---------------- Code disassembly (best guess): 0: 0f 84 af 02 00 00 je 0x2b5 6: 49 8d 7c 24 21 lea 0x21(%r12),%rdi b: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 12: fc ff df 15: 48 89 fa mov %rdi,%rdx 18: 48 c1 ea 03 shr $0x3,%rdx 1c: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax 20: 48 89 fa mov %rdi,%rdx 23: 83 e2 07 and $0x7,%edx 26: 38 d0 cmp %dl,%al 28: 7f 08 jg 0x32 * 2a: 84 c0 test %al,%al <-- trapping instruction 2c: 0f 85 dc 38 00 00 jne 0x390e 32: 41 0f b6 54 24 21 movzbl 0x21(%r12),%edx 38: 84 d2 test %dl,%dl 3a: 0f 88 c2 0b 00 00 js 0xc02