Extracting prog: 3m44.014625058s
Minimizing prog: 55m5.789291787s
Simplifying prog options: 8m39.729910713s
Extracting C: 2m19.079358639s
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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))
timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0)

program crashed: INFO: rcu detected stall in sys_getpid
single: successfully extracted reproducer
found reproducer with 4 syscalls
minimizing guilty program
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}}): prlimit64-sched_setscheduler-timer_create
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))

program did not crash
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}}): prlimit64-sched_setscheduler-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
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: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}}): prlimit64-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))
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: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}}): sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))
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: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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, 0x0, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))
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: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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, 0x0)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))
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: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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, 0x0, &(0x7f0000000100))
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: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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, &(0x7f0000000680)={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: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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))
timer_settime(0x0, 0x0, 0x0, 0x0)

program did not crash
extracting C reproducer
testing compiled C 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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
program crashed: INFO: rcu detected stall in syscall_exit_to_user_mode
a never seen crash title: INFO: rcu detected stall in syscall_exit_to_user_mode, ignore
simplifying guilty program options
testing program (duration=6m0s, {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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))
timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0)

program crashed: INFO: rcu detected stall in batadv_nc_worker
a never seen crash title: INFO: rcu detected stall in batadv_nc_worker, ignore
testing program (duration=6m0s, {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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))
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: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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))
timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0)

program crashed: INFO: rcu detected stall in syscall_exit_to_user_mode
validation run: crashed=true
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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))
timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0)

program crashed: INFO: rcu detected stall in syscall_exit_to_user_mode
validation run: crashed=true
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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))
timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0)

program crashed: INFO: rcu detected stall in corrupted
validation run: crashed=true
reproducing took 1h17m57.957455028s
repro crashed as (corrupted=true):
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
	(detected by 1, t=10502 jiffies, g=7961, q=81)
rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294955727-4294945224), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10504 jiffies! g7961 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:28016 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
 rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x9b/0x370 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4365 Comm: syz.1.18 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:lock_acquire+0xe0/0x400 kernel/locking/lockdep.c:5596
Code: 44 89 f0 48 0f a3 05 b7 de 2c 0c 73 0d e8 a8 ce 07 00 84 c0 0f 84 2d 02 00 00 48 c7 c0 c4 23 8a 8d 48 c1 e8 03 42 0f b6 04 38 <84> c0 0f 85 1c 02 00 00 83 3d 25 12 2d 0c 00 0f 84 0a 01 00 00 65
RSP: 0018:ffffc9000332f960 EFLAGS: 00000807
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 04995339cd74c000
RDX: 0000000000000000 RSI: ffffffff8a79fde0 RDI: ffffffff8a79fda0
RBP: ffffc9000332fa68 R08: ffffffff8d89f02f R09: 1ffffffff1b13e05
R10: dffffc0000000000 R11: fffffbfff1b13e06 R12: ffff88802ab0a518
R13: 1ffff92000665f38 R14: 0000000000000000 R15: dffffc0000000000
FS:  00007fe1d229a6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 0000000074ece000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline]
 _raw_spin_lock_irq+0xab/0xf0 kernel/locking/spinlock.c:170
 spin_lock_irq include/linux/spinlock.h:389 [inline]
 __set_current_blocked+0xe7/0x240 kernel/signal.c:3086
 set_current_blocked kernel/signal.c:3072 [inline]
 signal_delivered kernel/signal.c:2936 [inline]
 signal_setup_done+0x2e6/0x490 kernel/signal.c:2947
 handle_signal arch/x86/kernel/signal.c:842 [inline]
 arch_do_signal_or_restart+0xedc/0x12c0 arch/x86/kernel/signal.c:869
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fe1d2c58350
Code: 83 c0 16 83 e0 f7 74 12 50 48 8d 3d 52 1d 07 00 e8 65 65 f9 ff 0f 1f 44 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <83> ff 21 74 0b c3 66 2e 0f 1f 84 00 00 00 00 00 55 53 48 89 f3 48
RSP: 002b:00007fe1d2299b38 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007fe1d2eb1fa8 RCX: 00007fe1d2c38dd9
RDX: 00007fe1d2299b40 RSI: 00007fe1d2299c70 RDI: 0000000000000021
RBP: 00007fe1d2eb1fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe1d2eb2038 R14: 00007ffcc9e281f0 R15: 00007ffcc9e282d8
 </TASK>

report is corrupted, running repro again
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}}): prlimit64-sched_setscheduler-timer_create-timer_settime
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x1, &(0x7f0000000080)=0x7)
timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100))
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 self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=693/1/0x4000000000000000 softirq=7269/7279 fqs=3 
	(t=10500 jiffies g=8705 q=596)
rcu: rcu_preempt kthread starved for 10493 jiffies! g8705 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:28176 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
 rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x9b/0x370 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: 4380 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3681 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3701 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3756 [inline]
RIP: 0010:__lock_acquire+0x141b/0x7d10 kernel/locking/lockdep.c:5012
Code: c6 03 00 00 48 b8 eb 83 b5 80 46 86 c8 61 49 0f af c4 48 c1 e8 2d 48 8d 1c c5 00 50 d4 8f 48 89 d8 48 c1 e8 03 48 89 44 24 50 <42> 80 3c 00 00 74 12 48 89 df e8 46 29 61 00 49 b8 00 00 00 00 00
RSP: 0018:ffffc90000dd0a60 EFLAGS: 00000806
RAX: 1ffffffff2026f82 RBX: ffffffff90137c10 RCX: ffffffff815d29ac
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff901d50c8
RBP: ffffc90000dd0cb0 R08: dffffc0000000000 R09: 1ffffffff203aa19
R10: dffffc0000000000 R11: fffffbfff203aa1a R12: abe92a66ad81a2ce
R13: ffff88801dd88000 R14: 00000000ad81a2ce R15: ffff88801dd88b10
FS:  00007ff2dc8746c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 000000007b15f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
 hrtimer_interrupt+0xf8/0x8d0 kernel/time/hrtimer.c:1792
 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_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: 00 00 00 66 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 be 59 97 f7 48 89 df e8 f6 31 98 f7 e8 01 27 b9 f7 fb bf 01 00 00 00 <e8> d6 38 8c f7 65 8b 05 67 36 3c 76 85 c0 74 02 5b c3 e8 b4 43 3a
RSP: 0018:ffffc9000362fbc0 EFLAGS: 00000282
RAX: 53a44f6fbb7ee500 RBX: ffff8880780b65c0 RCX: 53a44f6fbb7ee500
RDX: dffffc0000000000 RSI: ffffffff8a2b2800 RDI: 0000000000000001
RBP: 0000000000000000 R08: ffff8880780b65c3 R09: 1ffff1100f016cb8
R10: dffffc0000000000 R11: ffffed100f016cb9 R12: ffff8880780b65c0
R13: 0000000000000021 R14: dffffc0000000000 R15: 000000001c000004
 spin_unlock_irq include/linux/spinlock.h:414 [inline]
 get_signal+0x11d6/0x12c0 kernel/signal.c:2903
 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ff2dd212dd7
Code: 83 c8 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
RSP: 002b:00007ff2dc8740e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007ff2dd48bfa8 RCX: 00007ff2dd212dd9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007ff2dd48bfa8
RBP: 00007ff2dd48bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff2dd48c038 R14: 00007ffdcc9c7020 R15: 00007ffdcc9c7108
 </TASK>
NMI backtrace for cpu 0
CPU: 0 PID: 4381 Comm: syz.1.18 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <IRQ>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_dump_cpu_stacks+0x22f/0x380 kernel/rcu/tree_stall.h:349
 print_cpu_stall+0x31d/0x5f0 kernel/rcu/tree_stall.h:633
 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x6ea/0x1120 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:2021
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4b4/0xb70 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_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: 00 00 00 66 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 be 59 97 f7 48 89 df e8 f6 31 98 f7 e8 01 27 b9 f7 fb bf 01 00 00 00 <e8> d6 38 8c f7 65 8b 05 67 36 3c 76 85 c0 74 02 5b c3 e8 b4 43 3a
RSP: 0018:ffffc9000363fbc0 EFLAGS: 00000282
RAX: 1c602281a0ff3b00 RBX: ffff8880780b5c80 RCX: 1c602281a0ff3b00
RDX: dffffc0000000000 RSI: ffffffff8a2b2800 RDI: 0000000000000001
RBP: 0000000000000000 R08: ffff8880780b5c83 R09: 1ffff1100f016b90
R10: dffffc0000000000 R11: ffffed100f016b91 R12: ffff8880780b5c80
R13: 0000000000000021 R14: dffffc0000000000 R15: 000000001c000004
 spin_unlock_irq include/linux/spinlock.h:414 [inline]
 get_signal+0x11d6/0x12c0 kernel/signal.c:2903
 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8eaec40dd7
Code: 83 c8 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
RSP: 002b:00007f8eae2a20e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f8eaeeb9fa8 RCX: 00007f8eaec40dd9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f8eaeeb9fa8
RBP: 00007f8eaeeb9fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8eaeeba038 R14: 00007fff46f56b70 R15: 00007fff46f56c58
 </TASK>
sched: RT throttling activated