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INFO: rcu detected stall in packet_sendmsg (3)

Status: auto-closed as invalid on 2022/08/21 13:12
Subsystems: net
[Documentation on labels]
First crash: 763d, last: 675d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in packet_sendmsg (2) net 10 1514d 1611d 0/26 auto-closed as invalid on 2020/05/03 17:34
upstream INFO: rcu detected stall in packet_sendmsg net 10 1656d 1662d 13/26 fixed on 2019/10/09 10:54

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=933/1/0x4000000000000000 softirq=46297/46298 fqs=5249 
	(t=10502 jiffies g=66377 q=857)
NMI backtrace for cpu 0
CPU: 0 PID: 20130 Comm: syz-executor.4 Not tainted 5.17.0-rc5-syzkaller-00021-g23d04328444a #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:111
 nmi_trigger_cpumask_backtrace+0x1e6/0x230 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:604 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:688 [inline]
 rcu_pending kernel/rcu/tree.c:3919 [inline]
 rcu_sched_clock_irq.cold+0x402/0x755 kernel/rcu/tree.c:2617
 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:1428
 __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+0x7/0x40 kernel/kcov.c:166
Code: 00 e9 59 fe ff ff 48 8b 7c 24 08 e8 c3 96 47 00 e9 61 fd ff ff cc cc cc cc cc cc cc cc cc cc cc cc cc cc 65 8b 05 a9 88 89 7e <89> c2 81 e2 00 01 00 00 a9 00 01 ff 00 74 10 31 c0 85 d2 74 15 8b
RSP: 0018:ffffc9000f4ef440 EFLAGS: 00000246
RAX: 0000000000000201 RBX: 00000000000000aa RCX: 00000000000000aa
RDX: 0000000000040000 RSI: ffff88807abad700 RDI: 0000000000000003
RBP: 0000000000000054 R08: 0000000000001fff R09: 0000000000000000
R10: ffffffff8761c401 R11: 0000000000000000 R12: ffff8880199f82c0
R13: 00000000000000a9 R14: 0000000000000000 R15: dffffc0000000000
 write_comp_data kernel/kcov.c:221 [inline]
 __sanitizer_cov_trace_const_cmp4+0x1c/0x70 kernel/kcov.c:287
 cake_heapify+0x221/0x3d0 net/sched/sch_cake.c:1434
 cake_drop net/sched/sch_cake.c:1515 [inline]
 cake_enqueue+0x13b0/0x3a00 net/sched/sch_cake.c:1903
 dev_qdisc_enqueue+0x40/0x300 net/core/dev.c:3668
 __dev_xmit_skb net/core/dev.c:3756 [inline]
 __dev_queue_xmit+0x1f61/0x3660 net/core/dev.c:4081
 packet_snd net/packet/af_packet.c:3057 [inline]
 packet_sendmsg+0x2226/0x52b0 net/packet/af_packet.c:3084
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x331/0x810 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmmsg+0x195/0x470 net/socket.c:2553
 __do_sys_sendmmsg net/socket.c:2582 [inline]
 __se_sys_sendmmsg net/socket.c:2579 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2579
 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: 0033:0x7fe82c9bf059
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe82b334168 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fe82cad1f60 RCX: 00007fe82c9bf059
RDX: 0000000000000001 RSI: 0000000020003000 RDI: 0000000000000003
RBP: 00007fe82ca1908d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe82d005b1f R14: 00007fe82b334300 R15: 0000000000022000
 </TASK>
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	e9 59 fe ff ff       	jmpq   0xfffffe5e
   5:	48 8b 7c 24 08       	mov    0x8(%rsp),%rdi
   a:	e8 c3 96 47 00       	callq  0x4796d2
   f:	e9 61 fd ff ff       	jmpq   0xfffffd75
  14:	cc                   	int3
  15:	cc                   	int3
  16:	cc                   	int3
  17:	cc                   	int3
  18:	cc                   	int3
  19:	cc                   	int3
  1a:	cc                   	int3
  1b:	cc                   	int3
  1c:	cc                   	int3
  1d:	cc                   	int3
  1e:	cc                   	int3
  1f:	cc                   	int3
  20:	cc                   	int3
  21:	cc                   	int3
  22:	65 8b 05 a9 88 89 7e 	mov    %gs:0x7e8988a9(%rip),%eax        # 0x7e8988d2
* 29:	89 c2                	mov    %eax,%edx <-- trapping instruction
  2b:	81 e2 00 01 00 00    	and    $0x100,%edx
  31:	a9 00 01 ff 00       	test   $0xff0100,%eax
  36:	74 10                	je     0x48
  38:	31 c0                	xor    %eax,%eax
  3a:	85 d2                	test   %edx,%edx
  3c:	74 15                	je     0x53
  3e:	8b                   	.byte 0x8b

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/02/24 13:06 upstream 23d04328444a b28851a4 .config console log report info ci-upstream-kasan-gce INFO: rcu detected stall in packet_sendmsg
2022/05/23 13:04 linux-next cc63e8e92cb8 4c7657cb .config console log report info ci-upstream-linux-next-kasan-gce-root BUG: soft lockup in packet_sendmsg
* Struck through repros no longer work on HEAD.