Extracting prog: 4m25.34777362s Minimizing prog: 35m16.82330527s Simplifying prog options: 8m31.964944063s Extracting C: 2m27.362254714s Simplifying C: 0s extracting reproducer from 1 programs testing a last program of every proc single: executing 1 programs separately with timeout 6m0s testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_route-sendmsg$nl_route_sched detailed listing: executing program 0: r0 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route_sched(r0, &(0x7f0000000300)={0x0, 0x0, &(0x7f0000000400)={&(0x7f0000000540)=@newqdisc={0xa4, 0x24, 0x605, 0x0, 0x0, {0x0, 0x0, 0x0, 0x2a, {0x0, 0x1}, {0xffff, 0xffff}}, [@qdisc_kind_options=@q_taprio={{0xb}, {0x74, 0x2, [@TCA_TAPRIO_ATTR_PRIOMAP={0x56, 0x1, {0x1, [], 0x0, [0x1, 0x56, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xfffd], [0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x3, 0x0, 0x0, 0x0, 0x0, 0x4]}}, @TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST={0x10, 0x2, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, [@TCA_TAPRIO_SCHED_ENTRY_INTERVAL={0x8, 0x4, 0x1000}]}]}, @TCA_TAPRIO_ATTR_SCHED_CLOCKID={0x8}]}}]}, 0xa4}}, 0x0) program crashed: INFO: rcu detected stall in corrupted single: successfully extracted reproducer found reproducer with 2 syscalls minimizing guilty program testing program (duration=5m46.709167848s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_route detailed listing: executing program 0: socket$nl_route(0x10, 0x3, 0x0) program did not crash testing program (duration=5m46.709167848s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): sendmsg$nl_route_sched detailed listing: executing program 0: sendmsg$nl_route_sched(0xffffffffffffffff, &(0x7f0000000300)={0x0, 0x0, &(0x7f0000000400)={&(0x7f0000000540)=@newqdisc={0xa4, 0x24, 0x605, 0x0, 0x0, {0x0, 0x0, 0x0, 0x2a, {0x0, 0x1}, {0xffff, 0xffff}}, [@qdisc_kind_options=@q_taprio={{0xb}, {0x74, 0x2, [@TCA_TAPRIO_ATTR_PRIOMAP={0x56, 0x1, {0x1, [], 0x0, [0x1, 0x56, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xfffd], [0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x3, 0x0, 0x0, 0x0, 0x0, 0x4]}}, @TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST={0x10, 0x2, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, [@TCA_TAPRIO_SCHED_ENTRY_INTERVAL={0x8, 0x4, 0x1000}]}]}, @TCA_TAPRIO_ATTR_SCHED_CLOCKID={0x8}]}}]}, 0xa4}}, 0x0) program did not crash testing program (duration=5m46.709167848s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_route-sendmsg$nl_route_sched detailed listing: executing program 0: r0 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route_sched(r0, 0x0, 0x0) program did not crash testing program (duration=5m46.709167848s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_route-sendmsg$nl_route_sched detailed listing: executing program 0: r0 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route_sched(r0, &(0x7f0000000300)={0x0, 0x0, 0x0}, 0x0) program did not crash testing program (duration=5m46.709167848s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_route-sendmsg$nl_route_sched detailed listing: executing program 0: r0 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route_sched(r0, &(0x7f0000000300)={0x0, 0x0, &(0x7f0000000400)={0x0}}, 0x0) program did not crash testing program (duration=5m46.709167848s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_route-sendmsg$nl_route_sched detailed listing: executing program 0: r0 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route_sched(r0, &(0x7f0000000300)={0x0, 0x0, &(0x7f0000000400)={&(0x7f0000000540)=@newqdisc={0x34, 0x24, 0x605, 0x0, 0x0, {0x0, 0x0, 0x0, 0x2a, {0x0, 0x1}, {0xffff, 0xffff}}, [@qdisc_kind_options=@q_taprio={{0xb}, {0x4}}]}, 0x34}}, 0x0) program did not crash extracting C reproducer testing compiled C program (duration=5m46.709167848s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_route-sendmsg$nl_route_sched program crashed: INFO: rcu detected stall in smp_call_function a never seen crash title: INFO: rcu detected stall in smp_call_function, ignore simplifying guilty program options testing program (duration=5m46.709167848s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_route-sendmsg$nl_route_sched detailed listing: executing program 0: r0 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route_sched(r0, &(0x7f0000000300)={0x0, 0x0, &(0x7f0000000400)={&(0x7f0000000540)=@newqdisc={0xa4, 0x24, 0x605, 0x0, 0x0, {0x0, 0x0, 0x0, 0x2a, {0x0, 0x1}, {0xffff, 0xffff}}, [@qdisc_kind_options=@q_taprio={{0xb}, {0x74, 0x2, [@TCA_TAPRIO_ATTR_PRIOMAP={0x56, 0x1, {0x1, [], 0x0, [0x1, 0x56, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xfffd], [0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x3, 0x0, 0x0, 0x0, 0x0, 0x4]}}, @TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST={0x10, 0x2, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, [@TCA_TAPRIO_SCHED_ENTRY_INTERVAL={0x8, 0x4, 0x1000}]}]}, @TCA_TAPRIO_ATTR_SCHED_CLOCKID={0x8}]}}]}, 0xa4}}, 0x0) program crashed: INFO: rcu detected stall in smp_call_function a never seen crash title: INFO: rcu detected stall in smp_call_function, ignore testing program (duration=5m46.709167848s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_route-sendmsg$nl_route_sched detailed listing: executing program 0: r0 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route_sched(r0, &(0x7f0000000300)={0x0, 0x0, &(0x7f0000000400)={&(0x7f0000000540)=@newqdisc={0xa4, 0x24, 0x605, 0x0, 0x0, {0x0, 0x0, 0x0, 0x2a, {0x0, 0x1}, {0xffff, 0xffff}}, [@qdisc_kind_options=@q_taprio={{0xb}, {0x74, 0x2, [@TCA_TAPRIO_ATTR_PRIOMAP={0x56, 0x1, {0x1, [], 0x0, [0x1, 0x56, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xfffd], [0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x3, 0x0, 0x0, 0x0, 0x0, 0x4]}}, @TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST={0x10, 0x2, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, [@TCA_TAPRIO_SCHED_ENTRY_INTERVAL={0x8, 0x4, 0x1000}]}]}, @TCA_TAPRIO_ATTR_SCHED_CLOCKID={0x8}]}}]}, 0xa4}}, 0x0) program did not crash testing program (duration=5m46.709167848s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_route-sendmsg$nl_route_sched detailed listing: executing program 0: r0 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route_sched(r0, &(0x7f0000000300)={0x0, 0x0, &(0x7f0000000400)={&(0x7f0000000540)=@newqdisc={0xa4, 0x24, 0x605, 0x0, 0x0, {0x0, 0x0, 0x0, 0x2a, {0x0, 0x1}, {0xffff, 0xffff}}, [@qdisc_kind_options=@q_taprio={{0xb}, {0x74, 0x2, [@TCA_TAPRIO_ATTR_PRIOMAP={0x56, 0x1, {0x1, [], 0x0, [0x1, 0x56, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xfffd], [0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x3, 0x0, 0x0, 0x0, 0x0, 0x4]}}, @TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST={0x10, 0x2, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, [@TCA_TAPRIO_SCHED_ENTRY_INTERVAL={0x8, 0x4, 0x1000}]}]}, @TCA_TAPRIO_ATTR_SCHED_CLOCKID={0x8}]}}]}, 0xa4}}, 0x0) program crashed: INFO: rcu detected stall in corrupted validation run: crashed=true testing program (duration=5m46.709167848s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_route-sendmsg$nl_route_sched detailed listing: executing program 0: r0 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route_sched(r0, &(0x7f0000000300)={0x0, 0x0, &(0x7f0000000400)={&(0x7f0000000540)=@newqdisc={0xa4, 0x24, 0x605, 0x0, 0x0, {0x0, 0x0, 0x0, 0x2a, {0x0, 0x1}, {0xffff, 0xffff}}, [@qdisc_kind_options=@q_taprio={{0xb}, {0x74, 0x2, [@TCA_TAPRIO_ATTR_PRIOMAP={0x56, 0x1, {0x1, [], 0x0, [0x1, 0x56, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xfffd], [0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x3, 0x0, 0x0, 0x0, 0x0, 0x4]}}, @TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST={0x10, 0x2, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, [@TCA_TAPRIO_SCHED_ENTRY_INTERVAL={0x8, 0x4, 0x1000}]}]}, @TCA_TAPRIO_ATTR_SCHED_CLOCKID={0x8}]}}]}, 0xa4}}, 0x0) program crashed: INFO: rcu detected stall in corrupted validation run: crashed=true testing program (duration=5m46.709167848s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_route-sendmsg$nl_route_sched detailed listing: executing program 0: r0 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route_sched(r0, &(0x7f0000000300)={0x0, 0x0, &(0x7f0000000400)={&(0x7f0000000540)=@newqdisc={0xa4, 0x24, 0x605, 0x0, 0x0, {0x0, 0x0, 0x0, 0x2a, {0x0, 0x1}, {0xffff, 0xffff}}, [@qdisc_kind_options=@q_taprio={{0xb}, {0x74, 0x2, [@TCA_TAPRIO_ATTR_PRIOMAP={0x56, 0x1, {0x1, [], 0x0, [0x1, 0x56, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xfffd], [0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x3, 0x0, 0x0, 0x0, 0x0, 0x4]}}, @TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST={0x10, 0x2, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, [@TCA_TAPRIO_SCHED_ENTRY_INTERVAL={0x8, 0x4, 0x1000}]}]}, @TCA_TAPRIO_ATTR_SCHED_CLOCKID={0x8}]}}]}, 0xa4}}, 0x0) program crashed: INFO: rcu detected stall in smp_call_function validation run: crashed=true reproducing took 1h2m19.096020653s repro crashed as (corrupted=false): rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10511 jiffies, g=15377, q=1077 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10511 (4294957499-4294946988), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10511 jiffies! g15377 f0x2 RCU_GP_WAIT_FQS(5) ->state=R ->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:R running task stack:27496 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5533 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7376 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5785 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:mark_lock+0x97/0x190 kernel/locking/lockdep.c:4775 Code: 83 3d b0 ea d6 0f 00 75 13 48 8d 3d 83 f9 d9 0f 48 c7 c6 52 2f 59 8e 67 48 0f b9 3a 90 31 c9 4c 89 fe 4c 89 f7 b8 01 00 00 00 <85> 69 60 74 10 5b 41 5c 41 5d 41 5e 41 5f 5d e9 55 e2 47 0a cc 49 RSP: 0018:ffffc90000a18b18 EFLAGS: 00000006 RAX: 0000000000000001 RBX: 0000000000000008 RCX: ffffffff953cc4d0 RDX: 0000000000000008 RSI: ffff88807c15ca80 RDI: ffff88807c15be80 RBP: 0000000000000100 R08: ffffffff84ec3ffa R09: 0000000000000001 R10: ffffc90000a18d58 R11: fffff520001431ad R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff888123bbf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe05ebc7e80 CR3: 000000000fb48000 CR4: 00000000003526f0 Call Trace: mark_usage kernel/locking/lockdep.c:4718 [inline] __lock_acquire+0x747/0x2de0 kernel/locking/lockdep.c:5242 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:155 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:181 debug_object_deactivate+0x9a/0x250 lib/debugobjects.c:936 debug_hrtimer_deactivate kernel/time/hrtimer.c:491 [inline] __run_hrtimer kernel/time/hrtimer.c:2042 [inline] __hrtimer_run_queues+0x239/0xa10 kernel/time/hrtimer.c:2131 hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2250 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline] __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:__sanitizer_cov_trace_pc+0x75/0x80 kernel/kcov.c:231 Code: 18 17 00 00 83 fa 02 75 21 48 8b 91 20 17 00 00 48 8b 32 48 8d 7e 01 8b 89 1c 17 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 cc cc cc cc cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90003d3f558 EFLAGS: 00000293 RAX: ffffffff81bbc5e8 RBX: ffff8880b8443708 RCX: ffff88807c15be80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90003d3f6b0 R08: ffffffff917a717f R09: 1ffffffff22f4e2f R10: dffffc0000000000 R11: fffffbfff22f4e30 R12: 1ffff110170886e1 R13: dffffc0000000000 R14: 1ffff1100f82ba83 R15: 0000000000000000 csd_lock_wait kernel/smp.c:363 [inline] smp_call_function_many_cond+0x1148/0x1500 kernel/smp.c:1002 __flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline] flush_tlb_mm_range+0x8ff/0x1090 arch/x86/mm/tlb.c:1435 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:509 [inline] tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:423 tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:549 free_ldt_pgtables+0x192/0x360 arch/x86/kernel/ldt.c:411 arch_exit_mmap arch/x86/include/asm/mmu_context.h:229 [inline] exit_mmap+0x1bf/0x9f0 mm/mmap.c:1300 __mmput+0x118/0x420 kernel/fork.c:1193 exit_mm+0x18e/0x240 kernel/exit.c:592 do_exit+0x6cd/0x2360 kernel/exit.c:974 do_group_exit+0x22d/0x2f0 kernel/exit.c:1129 __do_sys_exit_group kernel/exit.c:1140 [inline] __se_sys_exit_group kernel/exit.c:1138 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1138 x64_sys_call+0x18c6/0x18d0 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe05e4f16c5 Code: Unable to access opcode bytes at 0x7fe05e4f169b. RSP: 002b:00007ffe2f6de5e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000561f40b66040 RCX: 00007fe05e4f16c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000561f40b44910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe2f6de630 R14: 0000000000000000 R15: 0000000000000000 final repro crashed as (corrupted=false): rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10511 jiffies, g=15377, q=1077 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10511 (4294957499-4294946988), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10511 jiffies! g15377 f0x2 RCU_GP_WAIT_FQS(5) ->state=R ->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:R running task stack:27496 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5533 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7376 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5785 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:mark_lock+0x97/0x190 kernel/locking/lockdep.c:4775 Code: 83 3d b0 ea d6 0f 00 75 13 48 8d 3d 83 f9 d9 0f 48 c7 c6 52 2f 59 8e 67 48 0f b9 3a 90 31 c9 4c 89 fe 4c 89 f7 b8 01 00 00 00 <85> 69 60 74 10 5b 41 5c 41 5d 41 5e 41 5f 5d e9 55 e2 47 0a cc 49 RSP: 0018:ffffc90000a18b18 EFLAGS: 00000006 RAX: 0000000000000001 RBX: 0000000000000008 RCX: ffffffff953cc4d0 RDX: 0000000000000008 RSI: ffff88807c15ca80 RDI: ffff88807c15be80 RBP: 0000000000000100 R08: ffffffff84ec3ffa R09: 0000000000000001 R10: ffffc90000a18d58 R11: fffff520001431ad R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff888123bbf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe05ebc7e80 CR3: 000000000fb48000 CR4: 00000000003526f0 Call Trace: mark_usage kernel/locking/lockdep.c:4718 [inline] __lock_acquire+0x747/0x2de0 kernel/locking/lockdep.c:5242 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:155 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:181 debug_object_deactivate+0x9a/0x250 lib/debugobjects.c:936 debug_hrtimer_deactivate kernel/time/hrtimer.c:491 [inline] __run_hrtimer kernel/time/hrtimer.c:2042 [inline] __hrtimer_run_queues+0x239/0xa10 kernel/time/hrtimer.c:2131 hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2250 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline] __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:__sanitizer_cov_trace_pc+0x75/0x80 kernel/kcov.c:231 Code: 18 17 00 00 83 fa 02 75 21 48 8b 91 20 17 00 00 48 8b 32 48 8d 7e 01 8b 89 1c 17 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 cc cc cc cc cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90003d3f558 EFLAGS: 00000293 RAX: ffffffff81bbc5e8 RBX: ffff8880b8443708 RCX: ffff88807c15be80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90003d3f6b0 R08: ffffffff917a717f R09: 1ffffffff22f4e2f R10: dffffc0000000000 R11: fffffbfff22f4e30 R12: 1ffff110170886e1 R13: dffffc0000000000 R14: 1ffff1100f82ba83 R15: 0000000000000000 csd_lock_wait kernel/smp.c:363 [inline] smp_call_function_many_cond+0x1148/0x1500 kernel/smp.c:1002 __flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline] flush_tlb_mm_range+0x8ff/0x1090 arch/x86/mm/tlb.c:1435 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:509 [inline] tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:423 tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:549 free_ldt_pgtables+0x192/0x360 arch/x86/kernel/ldt.c:411 arch_exit_mmap arch/x86/include/asm/mmu_context.h:229 [inline] exit_mmap+0x1bf/0x9f0 mm/mmap.c:1300 __mmput+0x118/0x420 kernel/fork.c:1193 exit_mm+0x18e/0x240 kernel/exit.c:592 do_exit+0x6cd/0x2360 kernel/exit.c:974 do_group_exit+0x22d/0x2f0 kernel/exit.c:1129 __do_sys_exit_group kernel/exit.c:1140 [inline] __se_sys_exit_group kernel/exit.c:1138 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1138 x64_sys_call+0x18c6/0x18d0 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe05e4f16c5 Code: Unable to access opcode bytes at 0x7fe05e4f169b. RSP: 002b:00007ffe2f6de5e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000561f40b66040 RCX: 00007fe05e4f16c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000561f40b44910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe2f6de630 R14: 0000000000000000 R15: 0000000000000000