| Date | Name | Commit | Repro | Result |
|---|---|---|---|---|
| 2025/08/08 | linux-5.15.y (ToT) | c79648372d02 | C | [report] INFO: rcu detected stall in tc_modify_qdisc |
| 2025/08/08 | upstream (ToT) | 6e64f4580381 | C | Didn't crash |
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| Date | Name | Commit | Repro | Result |
|---|---|---|---|---|
| 2025/08/08 | linux-5.15.y (ToT) | c79648372d02 | C | [report] INFO: rcu detected stall in tc_modify_qdisc |
| 2025/08/08 | upstream (ToT) | 6e64f4580381 | C | Didn't crash |
| Created | Duration | User | Patch | Repo | Result |
|---|---|---|---|---|---|
| 2025/12/20 09:03 | 18m | retest repro | linux-5.15.y | report log | |
| 2025/11/06 22:58 | 12m | retest repro | linux-5.15.y | report log | |
| 2025/11/06 22:58 | 27m | retest repro | linux-5.15.y | report log | |
| 2025/10/23 11:04 | 11m | retest repro | linux-5.15.y | report log | |
| 2025/08/28 02:53 | 15m | retest repro | linux-5.15.y | report log | |
| 2025/08/23 05:40 | 12m | retest repro | linux-5.15.y | report log | |
| 2025/06/15 22:31 | 13m | retest repro | linux-5.15.y | report log | |
| 2025/05/28 06:55 | 33m | retest repro | linux-5.15.y | report log |
| Created | Duration | User | Patch | Repo | Result |
|---|---|---|---|---|---|
| 2025/07/20 05:34 | 1m | fix candidate | upstream | error job log | |
| 2025/05/16 12:55 | 10m | fix candidate | upstream | error job log | |
| 2025/04/06 19:03 | 1m | fix candidate | upstream | error job log | |
| 2025/02/23 08:17 | 1m | fix candidate | upstream | error job log | |
| 2024/12/13 18:21 | 1m | fix candidate | upstream | error job log | |
| 2024/11/04 08:18 | 11m | fix candidate | upstream | error job log |
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 ticks this GP) idle=249/1/0x4000000000000000 softirq=7130/7130 fqs=0 (detected by 0, t=10504 jiffies, g=6693, q=247) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4350 Comm: syz.0.17 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:kasan_mem_to_shadow include/linux/kasan.h:55 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x54/0x290 mm/kasan/generic.c:189 Code: 0f 82 43 02 00 00 49 bf 01 00 00 00 00 fc ff df 49 89 fb 49 c1 eb 03 49 b8 00 00 00 00 00 fc ff df 4f 8d 0c 03 48 8d 5c 37 ff <48> c1 eb 03 4e 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 4d 85 RSP: 0018:ffffc90000dd0b20 EFLAGS: 00000806 RAX: 0000000000000001 RBX: ffffffff8d699d2f RCX: ffffffff815c7c29 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d699d28 RBP: ffffc90000dd0c60 R08: dffffc0000000000 R09: fffffbfff1ad33a5 R10: ffffed10055ad625 R11: 1ffffffff1ad33a5 R12: ffff88807c1042e8 R13: dffffc0000000000 R14: ffff88807c104000 R15: dffffc0000000001 FS: 0000555585f7a500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000600 CR3: 000000007448d000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] cpumask_test_cpu include/linux/cpumask.h:344 [inline] cpu_online include/linux/cpumask.h:895 [inline] trace_lock_release include/trace/events/lock.h:58 [inline] lock_release+0xa9/0x870 kernel/locking/lockdep.c:5634 __raw_spin_unlock include/linux/spinlock_api_smp.h:150 [inline] _raw_spin_unlock+0x12/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:404 [inline] advance_sched+0x687/0x940 net/sched/sch_taprio.c:765 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x53d/0xc40 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194 Code: 74 05 e8 de 0d cb f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> f6 95 9e f7 65 8b 05 87 93 4f 76 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc900032aee00 EFLAGS: 00000206 RAX: bb3f6002be299600 RBX: 0000000000000a06 RCX: bb3f6002be299600 RDX: dffffc0000000000 RSI: ffffffff8a0b1c60 RDI: 0000000000000001 RBP: ffffc900032aee90 R08: dffffc0000000000 R09: fffffbfff1ff7c32 R10: fffffbfff1ff7c32 R11: 1ffffffff1ff7c31 R12: dffffc0000000000 R13: 187cd6309a9afb36 R14: ffff88807c1042e8 R15: 1ffff92000655dc0 spin_unlock_irqrestore include/linux/spinlock.h:419 [inline] taprio_change+0x3ff2/0x4ed0 net/sched/sch_taprio.c:1620 qdisc_create+0x7bd/0x1170 net/sched/sch_api.c:1265 tc_modify_qdisc+0xaa1/0x1770 net/sched/sch_api.c:-1 rtnetlink_rcv_msg+0x7ff/0xe90 net/core/rtnetlink.c:5684 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2446 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2500 __sys_sendmsg net/socket.c:2529 [inline] __do_sys_sendmsg net/socket.c:2538 [inline] __se_sys_sendmsg+0x190/0x250 net/socket.c:2536 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fae82f57749 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:00007fff21636c38 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fae831adfa0 RCX: 00007fae82f57749 RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 0000000000000004 RBP: 00007fae82fdbf91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fae831adfa0 R14: 00007fae831adfa0 R15: 0000000000000003 </TASK> rcu: rcu_preempt kthread timer wakeup didn't happen for 10503 jiffies! g6693 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=5722 rcu: rcu_preempt kthread starved for 10504 jiffies! g6693 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:28064 pid: 15 ppid: 2 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 </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: 4350 Comm: syz.0.17 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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_local_irq_save arch/x86/include/asm/irqflags.h:106 [inline] RIP: 0010:__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] RIP: 0010:_raw_spin_lock_irqsave+0x5d/0xf0 kernel/locking/spinlock.c:162 Code: a7 8b 48 c7 44 24 10 30 d9 b2 89 49 89 e7 49 c1 ef 03 48 b8 f1 f1 f1 f1 00 f3 f3 f3 49 bc 00 00 00 00 00 fc ff df 4b 89 04 27 <48> c7 44 24 20 00 00 00 00 9c 8f 44 24 20 4c 8b 74 24 20 fa 41 f7 RSP: 0018:ffffc90000dd0c00 EFLAGS: 00000802 RAX: f3f3f300f1f1f1f1 RBX: ffffffff9627dd60 RCX: 0000000000001b58 RDX: 0000000000010000 RSI: ffffffff8a0caf20 RDI: ffffffff9627dd60 RBP: ffffc90000dd0c80 R08: 0000000000000004 R09: 0000000000000003 R10: fffff520001ba180 R11: 1ffff920001ba180 R12: dffffc0000000000 R13: 1ffff1101722546a R14: dffffc0000000000 R15: 1ffff920001ba180 FS: 0000555585f7a500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000600 CR3: 000000007448d000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> debug_object_activate+0x65/0x480 lib/debugobjects.c:694 debug_hrtimer_activate kernel/time/hrtimer.c:410 [inline] debug_activate kernel/time/hrtimer.c:465 [inline] enqueue_hrtimer+0x30/0x370 kernel/time/hrtimer.c:1069 __run_hrtimer kernel/time/hrtimer.c:1702 [inline] __hrtimer_run_queues+0x65a/0xc40 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194 Code: 74 05 e8 de 0d cb f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> f6 95 9e f7 65 8b 05 87 93 4f 76 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc900032aee00 EFLAGS: 00000206 RAX: bb3f6002be299600 RBX: 0000000000000a06 RCX: bb3f6002be299600 RDX: dffffc0000000000 RSI: ffffffff8a0b1c60 RDI: 0000000000000001 RBP: ffffc900032aee90 R08: dffffc0000000000 R09: fffffbfff1ff7c32 R10: fffffbfff1ff7c32 R11: 1ffffffff1ff7c31 R12: dffffc0000000000 R13: 187cd6309a9afb36 R14: ffff88807c1042e8 R15: 1ffff92000655dc0 spin_unlock_irqrestore include/linux/spinlock.h:419 [inline] taprio_change+0x3ff2/0x4ed0 net/sched/sch_taprio.c:1620 qdisc_create+0x7bd/0x1170 net/sched/sch_api.c:1265 tc_modify_qdisc+0xaa1/0x1770 net/sched/sch_api.c:-1 rtnetlink_rcv_msg+0x7ff/0xe90 net/core/rtnetlink.c:5684 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2446 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2500 __sys_sendmsg net/socket.c:2529 [inline] __do_sys_sendmsg net/socket.c:2538 [inline] __se_sys_sendmsg+0x190/0x250 net/socket.c:2536 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fae82f57749 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:00007fff21636c38 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fae831adfa0 RCX: 00007fae82f57749 RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 0000000000000004 RBP: 00007fae82fdbf91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fae831adfa0 R14: 00007fae831adfa0 R15: 0000000000000003 </TASK>
| Time | Kernel | Commit | Syzkaller | Config | Log | Report | Syz repro | C repro | VM info | Assets (help?) | Manager | Title |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2025/11/30 16:39 | linux-5.15.y | cc5ec8769306 | d6526ea3 | .config | console log | report | syz / log | C | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | |
| 2025/08/02 12:40 | linux-5.15.y | c79648372d02 | 7368264b | .config | console log | report | syz / log | C | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | |
| 2024/11/10 16:34 | linux-5.15.y | 3c17fc483905 | 6b856513 | .config | console log | report | syz / log | C | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan-arm64 | BUG: soft lockup in tc_modify_qdisc | |
| 2024/10/27 18:53 | linux-5.15.y | 74cdd62cb470 | 65e8686b | .config | console log | report | syz / log | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan-arm64 | BUG: soft lockup in tc_modify_qdisc | ||
| 2025/12/05 11:00 | linux-5.15.y | cc5ec8769306 | d6526ea3 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/12/05 10:57 | linux-5.15.y | cc5ec8769306 | d6526ea3 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/12/05 00:58 | linux-5.15.y | cc5ec8769306 | d6526ea3 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/11/09 13:18 | linux-5.15.y | cc5ec8769306 | 4e1406b4 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/11/08 12:28 | linux-5.15.y | cc5ec8769306 | 4e1406b4 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/10/09 06:42 | linux-5.15.y | 29e53a5b1c4f | 7e2882b3 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/10/03 15:30 | linux-5.15.y | 29e53a5b1c4f | 49379ee0 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/10/03 15:28 | linux-5.15.y | 29e53a5b1c4f | 49379ee0 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/10/03 14:57 | linux-5.15.y | 29e53a5b1c4f | 49379ee0 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/09/25 22:59 | linux-5.15.y | 43bb85222e53 | 0abd0691 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/08/02 15:12 | linux-5.15.y | c79648372d02 | 7368264b | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/08/02 08:30 | linux-5.15.y | c79648372d02 | 7368264b | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/08/02 08:28 | linux-5.15.y | c79648372d02 | 7368264b | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/02/26 20:07 | linux-5.15.y | c16c81c81336 | d34966d1 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2025/02/10 07:55 | linux-5.15.y | c16c81c81336 | ef44b750 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2024/08/13 15:46 | linux-5.15.y | 7e89efd3ae1c | f21a18ca | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | INFO: rcu detected stall in tc_modify_qdisc | ||
| 2024/11/22 17:57 | linux-5.15.y | 0a51d2d4527b | 4b25d554 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan-arm64 | BUG: soft lockup in tc_modify_qdisc | ||
| 2024/09/17 19:58 | linux-5.15.y | 3a5928702e71 | c673ca06 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan-arm64 | BUG: soft lockup in tc_modify_qdisc |