syzbot


INFO: rcu detected stall in __do_softirq (2)

Status: auto-closed as invalid on 2021/01/10 17:25
Reported-by: syzbot+dd71c5c0d713d4f48d9f@syzkaller.appspotmail.com
First crash: 1001d, last: 816d
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 INFO: rcu detected stall in __do_softirq 1 1269d 1269d 0/1 auto-closed as invalid on 2019/10/25 08:47
linux-4.19 INFO: rcu detected stall in __do_softirq 2 1203d 1268d 0/1 auto-closed as invalid on 2019/12/20 09:57
upstream INFO: rcu detected stall in __do_softirq syz done 34 425d 1220d 0/24 upstream: reported syz repro on 2019/08/05 15:28

Sample crash report:
IDTVectoring: info=00000000 errcode=00000000
TSC Offset = 0xfffffdb71536e295
EPT pointer = 0x0000000054b1701e
Virtual processor ID = 0x0002
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (1 GPs behind) idle=2b6/1/0x4000000000000004 softirq=92372/92373 fqs=0 
rcu: 	 (t=11241 jiffies g=110637 q=1086)
rcu: rcu_preempt kthread starved for 11241 jiffies! g110637 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I29208    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_timeout+0x4cf/0xfe0 kernel/time/timer.c:1825
 rcu_gp_kthread+0xdad/0x21c0 kernel/rcu/tree.c:2202
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
NMI backtrace for cpu 1
CPU: 1 PID: 5010 Comm: syz-executor.3 Not tainted 4.19.145-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:77 [inline]
 dump_stack+0x1fc/0x2fe lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x15f/0x19c kernel/rcu/tree.c:1340
 print_cpu_stall kernel/rcu/tree.c:1478 [inline]
 check_cpu_stall kernel/rcu/tree.c:1550 [inline]
 __rcu_pending kernel/rcu/tree.c:3293 [inline]
 rcu_pending kernel/rcu/tree.c:3336 [inline]
 rcu_check_callbacks.cold+0x62d/0xe19 kernel/rcu/tree.c:2682
 update_process_times+0x2a/0xb0 kernel/time/timer.c:1650
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168
 tick_sched_timer+0xfc/0x290 kernel/time/tick-sched.c:1278
 __run_hrtimer kernel/time/hrtimer.c:1401 [inline]
 __hrtimer_run_queues+0x3f6/0xe60 kernel/time/hrtimer.c:1463
 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1521
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline]
 smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
RIP: 0010:__do_softirq+0x230/0x9a0 kernel/softirq.c:278
Code: c7 c0 58 5b d2 88 48 c1 e8 03 42 80 3c 38 00 0f 85 13 07 00 00 48 83 3d 35 59 72 01 00 0f 84 14 06 00 00 fb 66 0f 1f 44 00 00 <48> c7 44 24 08 c0 90 c0 88 b8 ff ff ff ff 0f bc 44 24 04 83 c0 01
RSP: 0018:ffff8880ae707f20 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11a4b6b RBX: ffff88808ac46180 RCX: 1ffff11011588d45
RDX: 0000000000000000 RSI: ffff88808ac46a08 RDI: ffff88808ac46a04
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000027
R13: 0000000000000027 R14: 0000000000000000 R15: dffffc0000000000
 invoke_softirq kernel/softirq.c:372 [inline]
 irq_exit+0x215/0x260 kernel/softirq.c:412
 exiting_irq arch/x86/include/asm/apic.h:544 [inline]
 do_IRQ+0x10c/0x1c0 arch/x86/kernel/irq.c:258
 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:670
 </IRQ>
RIP: 0010:vcpu_enter_guest arch/x86/kvm/x86.c:7736 [inline]
RIP: 0010:vcpu_run arch/x86/kvm/x86.c:7885 [inline]
RIP: 0010:kvm_arch_vcpu_ioctl_run+0x3237/0x6ec0 arch/x86/kvm/x86.c:8085
Code: 88 48 c1 e8 03 42 80 3c 28 00 0f 85 8c 30 00 00 48 83 3d 13 c1 c4 07 00 0f 84 b8 1d 00 00 e8 80 17 5c 00 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 2f 06 3a 00 65 8b 1d 68 53 f4 7e 31 ff 89 de e8
RSP: 0018:ffff8880378ffa10 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffd8
RAX: 0000000000040000 RBX: 0000000000000000 RCX: ffffc9000c0f5000
RDX: 0000000000040000 RSI: ffffffff810d9a50 RDI: ffff88808ac46a04
RBP: ffff8880378ffbb0 R08: ffffc9000e73d820 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000008
R13: dffffc0000000000 R14: ffff88804625036c R15: ffff888046250340
 kvm_vcpu_ioctl+0x493/0xe10 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2822
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688
 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45d5b9
Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007feaf6dfac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000011900 RCX: 000000000045d5b9
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007fff4fc22a4f R14: 00007feaf6dfb9c0 R15: 000000000118cf4c

Crashes (9):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-19 2020/09/12 17:24 linux-4.19.y a87f96283793 21d289c2 .config log report
ci2-linux-4-19 2020/08/19 17:14 linux-4.19.y a834132bd465 db787902 .config log report
ci2-linux-4-19 2020/05/08 16:33 linux-4.19.y 84920cc7fbe1 fe4122c3 .config log report
ci2-linux-4-19 2020/04/29 21:41 linux-4.19.y 765675379b62 2dd552a5 .config log report
ci2-linux-4-19 2020/04/02 04:18 linux-4.19.y 54b4fa6d3955 a34e2c33 .config log report
ci2-linux-4-19 2020/03/29 08:53 linux-4.19.y 54b4fa6d3955 05736b29 .config log report
ci2-linux-4-19 2020/03/23 23:30 linux-4.19.y 14cfdbd39e31 84f999d6 .config log report
ci2-linux-4-19 2020/03/12 11:34 linux-4.19.y 569209711609 d850e9d0 .config log report
ci2-linux-4-19 2020/03/11 09:56 linux-4.19.y 7472c4028e23 35f53e45 .config log report
* Struck through repros no longer work on HEAD.