Kernel panic - not syncing: kernel: panic_on_warn set ... CPU: 2 UID: 0 PID: 23178 Comm: syz.3.6319 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 vpanic+0x553/0x970 kernel/panic.c:651 panic+0xd1/0xe0 kernel/panic.c:788 check_panic_on_warn kernel/panic.c:525 [inline] check_panic_on_warn.cold+0x19/0x34 kernel/panic.c:520 __warn.cold+0x191/0x318 kernel/panic.c:1104 __report_bug+0x30f/0x440 lib/bug.c:254 report_bug_entry+0xe2/0x290 lib/bug.c:274 handle_bug+0x1cd/0x2a0 arch/x86/kernel/traps.c:431 exc_invalid_op+0x17/0x50 arch/x86/kernel/traps.c:490 asm_exc_invalid_op+0x1a/0x20 arch/x86/include/asm/idtentry.h:593 RIP: 0010:trace_rb_cpu_prepare+0x465/0x520 kernel/trace/ring_buffer.c:8107 Code: 48 c1 ea 03 80 3c 02 00 0f 84 bc fc ff ff 48 8b 3c 24 e8 9e d5 6e 00 e9 ae fc ff ff e8 c4 7e fb ff 48 8d 3d 0d 6a 39 10 89 ee <67> 48 0f b9 3a bb f4 ff ff ff e9 d3 fd ff ff 4c 89 ef e8 74 d5 6e RSP: 0000:ffffc90003c1f8b8 EFLAGS: 00010246 RAX: 0000000000080000 RBX: ffff888061d958b8 RCX: ffffc900270de000 RDX: 0000000000080000 RSI: 0000000000000000 RDI: ffffffff9249cc80 RBP: 0000000000000000 R08: ffff888026bacc80 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 R13: ffff888061d95810 R14: 0000000000000162 R15: 0000000000000000 cpuhp_invoke_callback+0x205/0x9a0 kernel/cpu.c:204 cpuhp_issue_call+0x1b8/0x970 kernel/cpu.c:2354 __cpuhp_state_add_instance_cpuslocked+0x2d7/0x400 kernel/cpu.c:2423 __cpuhp_state_add_instance+0xd5/0x2d0 kernel/cpu.c:2444 cpuhp_state_add_instance include/linux/cpuhotplug.h:377 [inline] alloc_buffer+0x6f8/0x1690 kernel/trace/ring_buffer.c:2920 __ring_buffer_alloc+0x2d/0x40 kernel/trace/ring_buffer.c:2962 allocate_trace_buffer+0x150/0xa30 kernel/trace/trace.c:8525 allocate_trace_buffers kernel/trace/trace.c:8558 [inline] trace_array_create_systems+0x582/0xc30 kernel/trace/trace.c:8736 trace_array_create kernel/trace/trace.c:8779 [inline] instance_mkdir+0xca/0x140 kernel/trace/trace.c:8794 tracefs_syscall_mkdir+0x10e/0x180 fs/tracefs/inode.c:121 vfs_mkdir+0x367/0x850 fs/namei.c:5420 filename_mkdirat+0x48b/0x5e0 fs/namei.c:5453 __do_sys_mkdirat fs/namei.c:5474 [inline] __se_sys_mkdirat fs/namei.c:5471 [inline] __ia32_sys_mkdirat+0x88/0xc0 fs/namei.c:5471 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline] __do_fast_syscall_32+0x14b/0x8c0 arch/x86/entry/syscall_32.c:282 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:307 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7f84fbc Code: d2 74 05 c1 e8 0c 89 02 8b 5d fc 31 c0 c9 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 2e 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 58 b8 RSP: 002b:00000000f543650c EFLAGS: 00000292 ORIG_RAX: 0000000000000128 RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 00000000800002c0 RDX: 00000000000001ff RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds.. ---------------- Code disassembly (best guess): 0: 48 c1 ea 03 shr $0x3,%rdx 4: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 8: 0f 84 bc fc ff ff je 0xfffffcca e: 48 8b 3c 24 mov (%rsp),%rdi 12: e8 9e d5 6e 00 call 0x6ed5b5 17: e9 ae fc ff ff jmp 0xfffffcca 1c: e8 c4 7e fb ff call 0xfffb7ee5 21: 48 8d 3d 0d 6a 39 10 lea 0x10396a0d(%rip),%rdi # 0x10396a35 28: 89 ee mov %ebp,%esi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: bb f4 ff ff ff mov $0xfffffff4,%ebx 34: e9 d3 fd ff ff jmp 0xfffffe0c 39: 4c 89 ef mov %r13,%rdi 3c: e8 .byte 0xe8 3d: 74 d5 je 0x14 3f: 6e outsb %ds:(%rsi),(%dx)