rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (10500 ticks this GP) idle=0ff/1/0x4000000000000000 softirq=78224/78224 fqs=4923 (t=10502 jiffies g=140505 q=26783) NMI backtrace for cpu 0 CPU: 0 PID: 6026 Comm: syz-executor.5 Not tainted 5.15.0-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_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2597 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:check_kcov_mode+0x2c/0x40 kernel/kcov.c:174 Code: 05 19 b5 8a 7e 89 c2 81 e2 00 01 00 00 a9 00 01 ff 00 74 10 31 c0 85 d2 74 15 8b 96 a4 15 00 00 85 d2 74 0b 8b 86 80 15 00 00 <39> f8 0f 94 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 31 c0 RSP: 0018:ffffc9000ff36f00 EFLAGS: 00000246 RAX: 0000000000000002 RBX: 000001e7f14b67e2 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff8881423e5700 RDI: 0000000000000003 RBP: 0000000000000000 R08: 000000000000019c R09: ffff888165059f4f R10: ffffffff8101e78b R11: 0000000000000001 R12: ffff888165059e10 R13: ffff888165059d60 R14: 0000000000000151 R15: ffffed102ca0b3e9 write_comp_data kernel/kcov.c:218 [inline] __sanitizer_cov_trace_const_cmp8+0x1d/0x70 kernel/kcov.c:291 msr_event_update+0x16b/0x240 arch/x86/events/msr.c:249 perf_output_read_group kernel/events/core.c:6922 [inline] perf_output_read+0xf02/0x1310 kernel/events/core.c:6961 perf_output_sample+0xd12/0x1d80 kernel/events/core.c:7008 __perf_event_output kernel/events/core.c:7493 [inline] perf_event_output_forward+0x119/0x280 kernel/events/core.c:7507 __perf_event_overflow+0x13c/0x3d0 kernel/events/core.c:9207 perf_swevent_overflow kernel/events/core.c:9283 [inline] perf_swevent_event+0x347/0x550 kernel/events/core.c:9311 do_perf_sw_event kernel/events/core.c:9424 [inline] ___perf_sw_event+0x31a/0x570 kernel/events/core.c:9455 __perf_sw_event+0x54/0x130 kernel/events/core.c:9467 perf_sw_event include/linux/perf_event.h:1174 [inline] mm_account_fault mm/memory.c:4747 [inline] handle_mm_fault+0x5ef/0x790 mm/memory.c:4798 do_user_addr_fault+0x489/0x11c0 arch/x86/mm/fault.c:1397 handle_page_fault arch/x86/mm/fault.c:1485 [inline] exc_page_fault+0x9e/0x180 arch/x86/mm/fault.c:1541 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:568 RIP: 0010:__get_user_nocheck_1+0x6/0x10 arch/x86/lib/getuser.S:124 Code: d0 73 64 48 19 d2 48 21 d0 0f 01 cb 48 8b 10 31 c0 0f 01 ca c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 0f 01 cb 0f ae e8 <0f> b6 10 31 c0 0f 01 ca c3 90 0f 01 cb 0f ae e8 0f b7 10 31 c0 0f RSP: 0018:ffffc9000ff377f0 EFLAGS: 00050246 RAX: 00000000201a4000 RBX: 00000000201a4000 RCX: ffffc90013d3f000 RDX: 0000000000040000 RSI: ffffffff81aaec9d RDI: 0000000000000003 RBP: 0000000000001000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff81aaec4f R11: 0000000000000000 R12: 00000000201a4000 R13: 1ffff92001fe6eff R14: 00000000201a5000 R15: 0000000000000000 fault_in_readable+0xd5/0x190 mm/gup.c:1783 fault_in_iov_iter_readable lib/iov_iter.c:459 [inline] fault_in_iov_iter_readable+0x11f/0x1f0 lib/iov_iter.c:445 generic_perform_write+0x15b/0x510 mm/filemap.c:3738 ext4_buffered_write_iter+0x1ac/0x3b0 fs/ext4/file.c:269 ext4_file_write_iter+0x423/0x14e0 fs/ext4/file.c:681 call_write_iter include/linux/fs.h:2162 [inline] aio_write+0x350/0x7a0 fs/aio.c:1577 __io_submit_one fs/aio.c:1832 [inline] io_submit_one+0xe09/0x1b80 fs/aio.c:1879 __do_sys_io_submit fs/aio.c:1938 [inline] __se_sys_io_submit fs/aio.c:1908 [inline] __x64_sys_io_submit+0x18c/0x330 fs/aio.c:1908 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: 0033:0x7f777cd7fae9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f777a2f5188 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1 RAX: ffffffffffffffda RBX: 00007f777ce92f60 RCX: 00007f777cd7fae9 RDX: 0000000020000540 RSI: 0000000000000008 RDI: 00007f777ce6e000 RBP: 00007f777cdd9f25 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc9f39188f R14: 00007f777a2f5300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 05 19 b5 8a 7e add $0x7e8ab519,%eax 5: 89 c2 mov %eax,%edx 7: 81 e2 00 01 00 00 and $0x100,%edx d: a9 00 01 ff 00 test $0xff0100,%eax 12: 74 10 je 0x24 14: 31 c0 xor %eax,%eax 16: 85 d2 test %edx,%edx 18: 74 15 je 0x2f 1a: 8b 96 a4 15 00 00 mov 0x15a4(%rsi),%edx 20: 85 d2 test %edx,%edx 22: 74 0b je 0x2f 24: 8b 86 80 15 00 00 mov 0x1580(%rsi),%eax * 2a: 39 f8 cmp %edi,%eax <-- trapping instruction 2c: 0f 94 c0 sete %al 2f: c3 retq 30: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1) 37: 00 00 00 00 3b: 0f 1f 00 nopl (%rax) 3e: 31 c0 xor %eax,%eax