Extracting prog: 5m15.580101483s Minimizing prog: 53m43.613025814s Simplifying prog options: 12m31.13269283s Extracting C: 3m51.132600176s 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:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in corrupted program crashed: INFO: rcu detected stall in corrupted single: successfully extracted reproducer found reproducer with 4 syscalls minimizing guilty program testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, 0x0, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, 0x0, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, 0x0) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, 0x0, 0x0) program crashed: lost connection to test machine suppressed program crash: lost connection to test machine extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime program crashed: INFO: rcu detected stall in worker_thread a never seen crash title: INFO: rcu detected stall in worker_thread, ignore simplifying guilty program options testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in corrupted extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime program crashed: INFO: rcu detected stall in worker_thread a never seen crash title: INFO: rcu detected stall in worker_thread, ignore testing program (duration=6m0s, {Threaded:false 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in corrupted validation run: crashed=true testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in corrupted validation run: crashed=true testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in corrupted validation run: crashed=true reproducing took 1h21m20.962839648s repro crashed as (corrupted=true): rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5942/1:b..l rcu: (detected by 1, t=10503 jiffies, g=10905, q=675 ncpus=2) task:sed state:R running task stack:23592 pid:5942 ppid:5941 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867 preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3a/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] wp_page_copy mm/memory.c:3202 [inline] do_wp_page+0x1f56/0x35f0 mm/memory.c:3469 handle_pte_fault mm/memory.c:5063 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x135d/0x4c00 mm/memory.c:5353 do_user_addr_fault+0xac8/0x12c0 arch/x86/mm/fault.c:1322 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7fa40c4a01b0 RSP: 002b:00007ffef243fde0 EFLAGS: 00010246 RAX: 00007fa40c4c34f8 RBX: 00007fa40c4c64a0 RCX: 0000000000000000 RDX: 0000000000000005 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fa40c4c65a0 R08: 00007ffef243fe50 R09: 0000000000000000 R10: 00007ffef243fd10 R11: 00007ffef243fdd0 R12: 00007fa40c4c34d0 R13: 00007fa40c7c9a08 R14: 0000000000000000 R15: 00007fa40c793ab0 rcu: rcu_preempt kthread starved for 10524 jiffies! g10905 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:27656 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x313/0x1590 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5943 Comm: syz.0.17 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:89 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:131 [inline] RIP: 0010:lock_release+0x565/0x8c0 kernel/locking/lockdep.c:5777 Code: 8a e8 6f 7a 1c 09 b8 ff ff ff ff 65 0f c1 05 ea d9 99 7e 83 f8 01 75 7f 43 c6 44 2f 04 00 48 c7 84 24 80 00 00 00 00 00 00 00 <9c> 8f 84 24 80 00 00 00 f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 RSP: 0018:ffffc90003517860 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 1afeb49dcf8acd47 RCX: cf950dc1531f9d00 RDX: 0000000000000002 RSI: ffffffff8acadae0 RDI: ffffffff8b1c85a0 RBP: ffffc90003517970 R08: ffffffff8e8aeeef R09: 1ffffffff1d15ddd R10: dffffc0000000000 R11: fffffbfff1d15dde R12: ffff888078416530 R13: dffffc0000000000 R14: ffff8880784164d0 R15: 1ffff920006a2f18 FS: 00005555566d4500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000006b000 CR3: 000000002fc3f000 CR4: 00000000003506f0 Call Trace: seqcount_lockdep_reader_access+0xe4/0x1d0 include/linux/seqlock.h:103 timekeeping_get_delta kernel/time/timekeeping.c:254 [inline] timekeeping_get_ns kernel/time/timekeeping.c:388 [inline] ktime_get+0x7f/0x280 kernel/time/timekeeping.c:848 clockevents_program_min_delta+0x55/0x340 kernel/time/clockevents.c:241 hrtimer_start_range_ns+0xbfb/0xff0 kernel/time/hrtimer.c:1352 posixtimer_rearm+0x135/0x340 kernel/time/posix-timers.c:268 dequeue_signal+0x1ba/0x4b0 kernel/signal.c:706 get_signal+0x551/0x13f0 kernel/signal.c:2782 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f713699c799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe661811d8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f7136c15fa0 RCX: 00007f713699c799 RDX: 000020000006b000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f7136a32bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7136c15fac R14: 00007f7136c15fa0 R15: 00007f7136c15fa0 report is corrupted, running repro again testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8) timer_create(0x0, &(0x7f0000000240)={0x0, 0x21}, &(0x7f0000bbdffc)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in syscall_exit_to_user_mode final repro crashed as (corrupted=false): rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=11545, q=534 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10500 (4294959182-4294948682), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10500 jiffies! g11545 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:26888 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x313/0x1590 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5937 Comm: syz.3.20 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:33 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:89 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:107 [inline] RIP: 0010:seqcount_lockdep_reader_access+0x8f/0x1d0 include/linux/seqlock.h:101 Code: 08 f8 f3 f3 f3 e8 c1 c5 0f 00 43 c6 44 3e 08 00 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 4c 8b 64 24 40 43 c6 44 3e 08 f8 fa <4c> 89 e6 48 81 e6 00 02 00 00 31 ff e8 d0 c9 0f 00 49 81 e4 00 02 RSP: 0018:ffffc90000007d80 EFLAGS: 00000006 RAX: ffffffff8177569f RBX: 000000000000a2fc RCX: ffff88802d16bc00 RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000007e20 R08: ffffffff8e8aeeef R09: 1ffffffff1d15ddd R10: dffffc0000000000 R11: fffffbfff1d15dde R12: 0000000000000006 R13: dffffc0000000000 R14: 1ffff92000000fb0 R15: dffffc0000000000 FS: 0000555567324500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000006b000 CR3: 000000007673a000 CR4: 00000000003506f0 Call Trace: timekeeping_get_delta kernel/time/timekeeping.c:254 [inline] timekeeping_get_ns kernel/time/timekeeping.c:388 [inline] ktime_get_update_offsets_now+0x99/0x3f0 kernel/time/timekeeping.c:2320 hrtimer_update_base kernel/time/hrtimer.c:661 [inline] hrtimer_interrupt+0x134/0x9c0 kernel/time/hrtimer.c:1858 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline] __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 Code: 00 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 aa ec d9 f6 48 89 df e8 62 c1 da f6 e8 1d ce fe f6 fb bf 01 00 00 00 82 c8 cd f6 65 8b 05 a3 f7 74 75 85 c0 74 02 5b c3 e8 20 df 71 RSP: 0018:ffffc90003537c78 EFLAGS: 00000286 RAX: 87fb8e3e90bfbf00 RBX: ffff88805f8b4a00 RCX: 87fb8e3e90bfbf00 RDX: dffffc0000000000 RSI: ffffffff8acac960 RDI: 0000000000000001 RBP: ffff88805f8b4e98 R08: ffffffff8e8aeeef R09: 1ffffffff1d15ddd R10: dffffc0000000000 R11: fffffbfff1d15dde R12: 1ffff1100bf169d3 R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000 spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x11f5/0x13f0 kernel/signal.c:2905 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f0232f9c799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd2eb135b8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f0233215fa0 RCX: 00007f0232f9c799 RDX: 000020000006b000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f0233032bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0233215fac R14: 00007f0233215fa0 R15: 00007f0233215fa0