syzbot


INFO: rcu detected stall in tc_modify_qdisc (2)

Status: upstream: reported on 2024/11/08 00:04
Reported-by: syzbot+3e756bb26a645ac581b7@syzkaller.appspotmail.com
First crash: 26d, last: 26d
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in tc_modify_qdisc 3 142d 181d 0/3 auto-obsoleted due to no activity on 2024/10/23 00:42
upstream INFO: rcu detected stall in tc_modify_qdisc net C done 544 4d08h 1589d 0/28 upstream: reported C repro on 2020/07/29 05:53
linux-5.15 INFO: rcu detected stall in tc_modify_qdisc origin:lts-only C error 5 11d 112d 0/3 upstream: reported C repro on 2024/08/13 15:46
android-6-1 BUG: soft lockup in tc_modify_qdisc C done done 53 372d 404d 0/2 auto-obsoleted due to no activity on 2024/02/06 04:01
android-5-15 BUG: soft lockup in tc_modify_qdisc origin:lts C done done 254 461d 516d 0/2 auto-obsoleted due to no activity on 2023/11/09 01:01
linux-5.15 BUG: soft lockup in tc_modify_qdisc origin:upstream C error 1 550d 550d 0/3 auto-obsoleted due to no activity on 2023/09/11 01:53
linux-6.1 BUG: soft lockup in tc_modify_qdisc origin:upstream C done 1 549d 549d 3/3 fixed on 2023/07/10 11:22
android-5-10 BUG: soft lockup in tc_modify_qdisc C done done 314 463d 516d 0/2 auto-obsoleted due to no activity on 2023/11/07 07:54

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (2 ticks this GP) idle=c8dc/1/0x4000000000000000 softirq=73095/73095 fqs=0
	(detected by 0, t=10502 jiffies, g=100733, q=266 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 18141 Comm: syz.1.4210 Not tainted 6.1.115-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline]
RIP: 0010:lock_release+0x5ed/0xa20 kernel/locking/lockdep.c:5685
Code: 14 0c 8b e8 f5 87 3c 09 b8 ff ff ff ff 65 0f c1 05 18 b4 97 7e 83 f8 01 0f 85 94 00 00 00 4c 89 f3 48 c1 eb 03 42 80 3c 3b 00 <74> 08 4c 89 f7 e8 e9 51 77 00 48 c7 84 24 90 00 00 00 00 00 00 00
RSP: 0018:ffffc900001e0b80 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 1ffff9200003c182 RCX: ffffc900001e0c03
RDX: 0000000000000001 RSI: ffffffff8b0c1440 RDI: ffffffff8b5d7540
RBP: ffffc900001e0cb0 R08: dffffc0000000000 R09: fffffbfff1d34076
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200003c17c
R13: 0000000000000046 R14: ffffc900001e0c10 R15: dffffc0000000000
FS:  00007f2e58be26c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2e58be1f98 CR3: 000000005d98f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
 _raw_spin_unlock_irqrestore+0x75/0x130 kernel/locking/spinlock.c:194
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4b0/0xe50 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lockdep_unregister_key+0x562/0x600 kernel/locking/lockdep.c:6367
Code: 1e 91 48 c7 c6 20 ea 6a 81 e8 0a b4 08 00 e8 45 c8 08 00 e9 ea fb ff ff e8 bb 49 3c 09 41 f7 c7 00 02 00 00 74 d0 fb 45 84 f6 <75> cf eb e0 0f 0b 45 31 f6 e9 64 ff ff ff 0f 0b e9 a5 fe ff ff 0f
RSP: 0018:ffffc9000329ef80 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 1ffff92000653df8 RCX: ffffffff97337103
RDX: 0000000000000001 RSI: ffffffff8b0c0fa0 RDI: ffffffff8b5d7540
RBP: ffffc9000329f048 R08: dffffc0000000000 R09: fffffbfff223c497
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc9000329efc0
R13: 1ffff92000653df4 R14: 0000000000000000 R15: 0000000000000206
 __qdisc_destroy+0x127/0x450 net/sched/sch_generic.c:1078
 taprio_attach+0x260/0x420 net/sched/sch_taprio.c:1844
 qdisc_graft+0x12e5/0x1610 net/sched/sch_api.c:1143
 tc_modify_qdisc+0xf29/0x1d70 net/sched/sch_api.c:1767
 rtnetlink_rcv_msg+0x818/0xff0 net/core/rtnetlink.c:6150
 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2508
 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
 netlink_unicast+0x7d8/0x970 net/netlink/af_netlink.c:1352
 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1874
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x5a5/0x8f0 net/socket.c:2519
 ___sys_sendmsg net/socket.c:2573 [inline]
 __sys_sendmsg+0x2a9/0x390 net/socket.c:2602
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2e57d7e719
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2e58be2038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f2e57f35f80 RCX: 00007f2e57d7e719
RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000004
RBP: 00007f2e57df139e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f2e57f35f80 R15: 00007ffef7f87c98
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g100733 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=49310
rcu: rcu_preempt kthread starved for 10502 jiffies! g100733 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:25528 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 18141 Comm: syz.1.4210 Not tainted 6.1.115-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__lock_acquire+0xdcd/0x1f80
Code: 84 c0 0f 85 62 0c 00 00 8b 1b 48 8b 44 24 30 0f b6 04 38 84 c0 0f 85 76 0c 00 00 48 8b 44 24 08 33 18 f7 c3 00 60 00 00 74 0d <41> bd 01 00 00 00 49 c7 c7 ff ff ff ff 48 8b 44 24 30 0f b6 04 38
RSP: 0018:ffffc900001e0a60 EFLAGS: 00000006
RAX: ffff88802778c6a8 RBX: 0000000000084c36 RCX: ffff88802778c660
RDX: 0000000000000000 RSI: 0000000000000008 RDI: dffffc0000000000
RBP: ffff88802778c688 R08: dffffc0000000000 R09: fffffbfff224607e
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88802778c658
R13: 0000000000000000 R14: ffff88802778c6a8 R15: fb268dbe5ff7dd64
FS:  00007f2e58be26c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2e58be1f98 CR3: 000000005d98f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 advance_sched+0x47/0x970 net/sched/sch_taprio.c:700
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lockdep_unregister_key+0x562/0x600 kernel/locking/lockdep.c:6367
Code: 1e 91 48 c7 c6 20 ea 6a 81 e8 0a b4 08 00 e8 45 c8 08 00 e9 ea fb ff ff e8 bb 49 3c 09 41 f7 c7 00 02 00 00 74 d0 fb 45 84 f6 <75> cf eb e0 0f 0b 45 31 f6 e9 64 ff ff ff 0f 0b e9 a5 fe ff ff 0f
RSP: 0018:ffffc9000329ef80 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 1ffff92000653df8 RCX: ffffffff97337103
RDX: 0000000000000001 RSI: ffffffff8b0c0fa0 RDI: ffffffff8b5d7540
RBP: ffffc9000329f048 R08: dffffc0000000000 R09: fffffbfff223c497
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc9000329efc0
R13: 1ffff92000653df4 R14: 0000000000000000 R15: 0000000000000206
 __qdisc_destroy+0x127/0x450 net/sched/sch_generic.c:1078
 taprio_attach+0x260/0x420 net/sched/sch_taprio.c:1844
 qdisc_graft+0x12e5/0x1610 net/sched/sch_api.c:1143
 tc_modify_qdisc+0xf29/0x1d70 net/sched/sch_api.c:1767
 rtnetlink_rcv_msg+0x818/0xff0 net/core/rtnetlink.c:6150
 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2508
 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
 netlink_unicast+0x7d8/0x970 net/netlink/af_netlink.c:1352
 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1874
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x5a5/0x8f0 net/socket.c:2519
 ___sys_sendmsg net/socket.c:2573 [inline]
 __sys_sendmsg+0x2a9/0x390 net/socket.c:2602
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2e57d7e719
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2e58be2038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f2e57f35f80 RCX: 00007f2e57d7e719
RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000004
RBP: 00007f2e57df139e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f2e57f35f80 R15: 00007ffef7f87c98
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/08 00:03 linux-6.1.y 7c15117f9468 867e44df .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in tc_modify_qdisc
* Struck through repros no longer work on HEAD.