syzbot


INFO: rcu detected stall in sys_io_submit

Status: auto-closed as invalid on 2022/02/05 09:08
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 390d, last: 390d

Sample crash report:
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:
 <IRQ>
 __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
 </IRQ>
 <TASK>
 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
 </TASK>
----------------
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

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-root 2021/11/07 09:00 upstream 512b7931ad05 4c1be0be .config log report info INFO: rcu detected stall in sys_io_submit
* Struck through repros no longer work on HEAD.