Hello, When using Healer to fuzz the latest Linux kernel, the following crash was triggered. HEAD commit: 4357f03d6611 Merge tag 'pm-5.15-rc2 git tree: upstream console output: https://drive.google.com/file/d/1gXBYGICW_aFSK8X-6NYECS6iIfHI66Nw/view?usp=sharing kernel config: https://drive.google.com/file/d/1HKZtF_s3l6PL3OoQbNq_ei9CdBus-Tz0/view?usp=sharing Sorry, I don't have a reproducer for this crash, hope the symbolized report can help. If you fix this issue, please add the following tag to the commit: Reported-by: Hao Sun <sunhao.th@xxxxxxxxx> INFO: task syz-executor:31998 blocked for more than 143 seconds. Not tainted 5.15.0-rc1+ #19 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:11144 pid:31998 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x323/0xae0 kernel/sched/core.c:6287 schedule+0x36/0xe0 kernel/sched/core.c:6366 rwsem_down_write_slowpath kernel/locking/rwsem.c:1107 [inline] __down_write_common.part.13+0x356/0x7a0 kernel/locking/rwsem.c:1262 deactivate_super+0x4b/0x80 fs/super.c:365 cleanup_mnt+0x138/0x1b0 fs/namespace.c:1137 task_work_run+0x86/0xd0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x271/0x280 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x40/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x46c777 RSP: 002b:00007ffd324c9358 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000046c777 RDX: 0000000000404e22 RSI: 0000000000000002 RDI: 00007ffd324c9420 RBP: 00007ffd324c9420 R08: 00000000025e5033 R09: 000000000000000b R10: 00000000fffffffb R11: 0000000000000246 R12: 00000000004e38c6 R13: 00007ffd324ca4d0 R14: 00007ffd324ca4cc R15: 0000000000000004 INFO: task syz-executor:1024 blocked for more than 143 seconds. Not tainted 5.15.0-rc1+ #19 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:12440 pid: 1024 ppid: 31998 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x323/0xae0 kernel/sched/core.c:6287 schedule+0x36/0xe0 kernel/sched/core.c:6366 wait_current_trans+0x122/0x1a0 fs/btrfs/transaction.c:534 start_transaction+0x3b5/0x970 fs/btrfs/transaction.c:681 btrfs_attach_transaction_barrier+0x21/0x60 fs/btrfs/transaction.c:837 btrfs_sync_fs+0x7e/0x430 fs/btrfs/super.c:1401 sync_fs_one_sb+0x40/0x50 fs/sync.c:81 iterate_supers+0xa7/0x130 fs/super.c:695 ksys_sync+0x60/0xc0 fs/sync.c:116 __do_sys_sync+0xa/0x10 fs/sync.c:125 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x34/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x200003ca RSP: 002b:00007eff022caba8 EFLAGS: 00000a83 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00000000200003ca RDX: 0000000000004c01 RSI: 0000000000000003 RDI: 0000000000400000 RBP: 00000000000000eb R08: 0000000000000005 R09: 0000000000000006 R10: 0000000000000007 R11: 0000000000000a83 R12: 000000000000000b R13: 000000000000000c R14: 000000000000000d R15: 00007ffd324ca3a0 INFO: task syz-executor:1054 blocked for more than 143 seconds. Not tainted 5.15.0-rc1+ #19 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:12440 pid: 1054 ppid: 31998 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x323/0xae0 kernel/sched/core.c:6287 schedule+0x36/0xe0 kernel/sched/core.c:6366 wait_current_trans+0x122/0x1a0 fs/btrfs/transaction.c:534 start_transaction+0x3b5/0x970 fs/btrfs/transaction.c:681 btrfs_attach_transaction_barrier+0x21/0x60 fs/btrfs/transaction.c:837 btrfs_sync_fs+0x7e/0x430 fs/btrfs/super.c:1401 sync_fs_one_sb+0x40/0x50 fs/sync.c:81 iterate_supers+0xa7/0x130 fs/super.c:695 ksys_sync+0x60/0xc0 fs/sync.c:116 __do_sys_sync+0xa/0x10 fs/sync.c:125 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x34/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x200003ca RSP: 002b:00007eff022caba8 EFLAGS: 00000a83 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00000000200003ca RDX: 0000000000004c01 RSI: 0000000000000003 RDI: 0000000000400000 RBP: 00000000000000eb R08: 0000000000000005 R09: 0000000000000006 R10: 0000000000000007 R11: 0000000000000a83 R12: 000000000000000b R13: 000000000000000c R14: 000000000000000d R15: 00007ffd324ca3a0 INFO: task syz-executor:1654 blocked for more than 143 seconds. Not tainted 5.15.0-rc1+ #19 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:12488 pid: 1654 ppid: 31998 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x323/0xae0 kernel/sched/core.c:6287 schedule+0x36/0xe0 kernel/sched/core.c:6366 rwsem_down_write_slowpath kernel/locking/rwsem.c:1107 [inline] __down_write_common.part.13+0x356/0x7a0 kernel/locking/rwsem.c:1262 __btrfs_tree_lock+0x2e/0x1a0 fs/btrfs/locking.c:112 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4740 [inline] btrfs_alloc_tree_block+0x19c/0x670 fs/btrfs/extent-tree.c:4818 __btrfs_cow_block+0x16f/0x820 fs/btrfs/ctree.c:415 btrfs_cow_block+0x12a/0x300 fs/btrfs/ctree.c:570 btrfs_search_slot+0x6b0/0xee0 fs/btrfs/ctree.c:1768 btrfs_update_root+0x6b/0x470 fs/btrfs/root-tree.c:134 commit_fs_roots+0x151/0x220 fs/btrfs/transaction.c:1373 btrfs_commit_transaction+0x443/0x1450 fs/btrfs/transaction.c:2265 btrfs_sync_fs+0x9a/0x430 fs/btrfs/super.c:1426 sync_fs_one_sb+0x40/0x50 fs/sync.c:81 iterate_supers+0xa7/0x130 fs/super.c:695 ksys_sync+0x60/0xc0 fs/sync.c:116 __do_sys_sync+0xa/0x10 fs/sync.c:125 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x34/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x2000030a RSP: 002b:00007eff022caba8 EFLAGS: 00000a83 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 000000002000030a RDX: 0000000000004c01 RSI: 0000000000000003 RDI: 0000000000400000 RBP: 00000000000000ab R08: 0000000000000005 R09: 0000000000000006 R10: 0000000000000007 R11: 0000000000000a83 R12: 000000000000000b R13: 000000000000000c R14: 000000000000000d R15: 00007ffd324ca3a0 INFO: lockdep is turned off. NMI backtrace for cpu 3 CPU: 3 PID: 39 Comm: khungtaskd Not tainted 5.15.0-rc1+ #19 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x8d/0xcf lib/dump_stack.c:106 nmi_cpu_backtrace+0x1e9/0x210 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x120/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0x4e1/0x980 kernel/hung_task.c:295 kthread+0x178/0x1b0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 3 to CPUs 0-2: NMI backtrace for cpu 2 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 2 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 2 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:716 NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 0 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:716 NMI backtrace for cpu 1 CPU: 1 PID: 3015 Comm: systemd-journal Not tainted 5.15.0-rc1+ #19 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 RIP: 0010:lookup_object lib/debugobjects.c:196 [inline] RIP: 0010:debug_object_activate+0xdb/0x230 lib/debugobjects.c:663 Code: 88 4c 89 f7 e8 86 16 fb 01 48 8b 9b 00 81 81 88 48 85 db 74 65 4c 3b 63 18 74 20 48 8b 1b ba 01 00 00 00 48 85 db 75 0a eb 52 <48> 8b 1b 48 85 db 74 4a 83 c2 01 4c 3b 63 18 75 ef 8b 53 10 83 fa RSP: 0018:ffffc9000087fe20 EFLAGS: 00000087 RAX: 0000000000000206 RBX: ffff888008c50d98 RCX: 0000000000000000 RDX: 0000000000000008 RSI: 0000000000000000 RDI: ffffffff888cc108 RBP: ffffc9000087fe80 R08: 0000000000000001 R09: 0000000000000000 R10: ffffc9000087fea0 R11: 0000000000000000 R12: ffff88810eb33000 R13: ffffffff8482f6a0 R14: ffffffff888cc108 R15: ffffffff8736e2d0 FS: 00007f839bff48c0(0000) GS:ffff88813dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8396a2c008 CR3: 0000000104716000 CR4: 0000000000750ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: debug_rcu_head_queue kernel/rcu/rcu.h:176 [inline] __call_rcu kernel/rcu/tree.c:2971 [inline] call_rcu+0x2c/0x320 kernel/rcu/tree.c:3067 task_work_run+0x86/0xd0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x271/0x280 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x40/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f839b58485d Code: bb 20 00 00 75 10 b8 02 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 b8 02 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 67 f6 ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffd9a511330 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: fffffffffffffffe RBX: 00007ffd9a511640 RCX: 00007f839b58485d RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 0000564967919cd0 RBP: 000000000000000d R08: 000000000000ffc0 R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000293 R12: 00000000ffffffff R13: 000056496790e040 R14: 00007ffd9a511600 R15: 0000564967911e80 ---------------- Code disassembly (best guess): 0: 88 4c 89 f7 mov %cl,-0x9(%rcx,%rcx,4) 4: e8 86 16 fb 01 callq 0x1fb168f 9: 48 8b 9b 00 81 81 88 mov -0x777e7f00(%rbx),%rbx 10: 48 85 db test %rbx,%rbx 13: 74 65 je 0x7a 15: 4c 3b 63 18 cmp 0x18(%rbx),%r12 19: 74 20 je 0x3b 1b: 48 8b 1b mov (%rbx),%rbx 1e: ba 01 00 00 00 mov $0x1,%edx 23: 48 85 db test %rbx,%rbx 26: 75 0a jne 0x32 28: eb 52 jmp 0x7c * 2a: 48 8b 1b mov (%rbx),%rbx <-- trapping instruction 2d: 48 85 db test %rbx,%rbx 30: 74 4a je 0x7c 32: 83 c2 01 add $0x1,%edx 35: 4c 3b 63 18 cmp 0x18(%rbx),%r12 39: 75 ef jne 0x2a 3b: 8b 53 10 mov 0x10(%rbx),%edx 3e: 83 .byte 0x83 3f: fa cli
