Extracting prog: 3m3.071963602s
Minimizing prog: 1h3m29.642475457s
Simplifying prog options: 18m20.340283146s
Extracting C: 5m15.676843223s
Simplifying C: 0s


extracting reproducer from 62 programs
testing a last program of every proc
single: executing 15 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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): prlimit64-sched_setscheduler-timer_create-timer_settime-openat$sndtimer-read
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8)
timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000))
timer_settime(0x0, 0x0, &(0x7f0000000240)={{0x0, 0x8}, {0x0, 0x9}}, 0x0)
r0 = openat$sndtimer(0xffffffffffffff9c, &(0x7f0000000000), 0x0)
read(r0, &(0x7f00000003c0)=""/4096, 0x20)

program crashed: INFO: rcu detected stall in corrupted
single: successfully extracted reproducer
found reproducer with 6 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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): prlimit64-sched_setscheduler-timer_create-timer_settime-openat$sndtimer
detailed listing:
executing program 0:
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x2, &(0x7f0000000080)=0x8)
timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000))
timer_settime(0x0, 0x0, &(0x7f0000000240)={{0x0, 0x8}, {0x0, 0x9}}, 0x0)
openat$sndtimer(0xffffffffffffff9c, &(0x7f0000000000), 0x0)

program crashed: INFO: rcu detected stall in corrupted
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 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, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000))
timer_settime(0x0, 0x0, &(0x7f0000000240)={{0x0, 0x8}, {0x0, 0x9}}, 0x0)

program crashed: INFO: rcu detected stall in corrupted
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 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, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000))

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 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, &(0x7f0000000240)={{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 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, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000))
timer_settime(0x0, 0x0, &(0x7f0000000240)={{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 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, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000))
timer_settime(0x0, 0x0, &(0x7f0000000240)={{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 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, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000))
timer_settime(0x0, 0x0, &(0x7f0000000240)={{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 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, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000))
timer_settime(0x0, 0x0, &(0x7f0000000240)={{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 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, &(0x7f0000000000))
timer_settime(0x0, 0x0, &(0x7f0000000240)={{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 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, &(0x7f0000000080)={0x0, 0x11}, 0x0)
timer_settime(0x0, 0x0, &(0x7f0000000240)={{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 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, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000))
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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): prlimit64-sched_setscheduler-timer_create-timer_settime
program crashed: no output from test machine
a never seen crash title: no output from test machine, 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 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, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000))
timer_settime(0x0, 0x0, &(0x7f0000000240)={{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: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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): prlimit64-sched_setscheduler-timer_create-timer_settime
program crashed: no output from test machine
a never seen crash title: no output from test machine, 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 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, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000))
timer_settime(0x0, 0x0, &(0x7f0000000240)={{0x0, 0x8}, {0x0, 0x9}}, 0x0)

program did not crash
reproducing took 1h30m7.470911214s
repro crashed as (corrupted=true):
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (1 GPs behind) idle=167c/1/0x4000000000000000 softirq=10694/10713 fqs=0
	(t=10500 jiffies g=10705 q=4014 ncpus=2)
rcu: rcu_preempt kthread starved for 10500 jiffies! g10705 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:26048 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 schedule+0xbf/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4429 Comm: syz.3.19 Not tainted 6.1.134-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:get_nohz_timer_target+0x469/0x540 kernel/sched/core.c:1099
Code: 00 48 c7 c2 a0 c9 0b 8b e8 44 57 0c 00 e8 bf a6 15 00 48 c7 c7 c0 e7 32 8d 48 8b 74 24 10 e8 ce 1c 0c 00 44 89 f8 48 83 c4 28 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 e8 e7 fb 52 09 85 c0 0f 84 64 fd
RSP: 0018:ffffc900034578b8 EFLAGS: 00000086
RAX: 0000000000000000 RBX: ffff8880b8e3b3a0 RCX: ffff8880251abb80
RDX: ffff8880251abb80 RSI: ffffffff8b5f7340 RDI: ffff8880b8e3b398
RBP: ffff8880251abb80 R08: ffffffff8179a4fd R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff8880b8e3a980 R15: 0000000000000000
FS:  000055557741a500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3305ffff CR3: 00000000317a3000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 get_target_base kernel/time/hrtimer.c:203 [inline]
 switch_hrtimer_base kernel/time/hrtimer.c:229 [inline]
 __hrtimer_start_range_ns kernel/time/hrtimer.c:1244 [inline]
 hrtimer_start_range_ns+0x5ba/0xc80 kernel/time/hrtimer.c:1292
 posixtimer_rearm+0x1ad/0x3f0 kernel/time/posix-timers.c:328
 dequeue_signal+0x245/0x590 kernel/signal.c:704
 get_signal+0x5ed/0x17a0 kernel/signal.c:2751
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f985998d169
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:00007ffe1a6710d8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f9859ba5fa0 RCX: 00007f985998d169
RDX: 0000200000000240 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f9859a0e990 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9859ba5fa0 R14: 00007f9859ba5fa0 R15: 0000000000000004
 </TASK>
CPU: 1 PID: 4428 Comm: syz.2.23 Not tainted 6.1.134-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: d1 83 f5 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 5e aa ae f6 48 89 df e8 c6 e8 af f6 e8 81 3a d5 f6 fb bf 01 00 00 00 <e8> d6 68 a2 f6 65 8b 05 97 3e 46 75 85 c0 74 02 5b c3 e8 34 62 44
RSP: 0018:ffffc90003d07b30 EFLAGS: 00000286
RAX: 6fb479a894d31c00 RBX: ffff88802f79ca00 RCX: ffffffff973c3103
RDX: dffffc0000000000 RSI: ffffffff8b0c1ec0 RDI: 0000000000000001
RBP: ffffc90003d07c70 R08: dffffc0000000000 R09: ffffed1005ef3941
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff11005ef3993
R13: 0000000004000000 R14: 0000000000000011 R15: ffff88802f79cc98
FS:  00005555896db500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32f5ffff CR3: 0000000029d26000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x151f/0x17a0 kernel/signal.c:2874
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ff28818d169
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:00007fff6b469848 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007ff2883a5fa0 RCX: 00007ff28818d169
RDX: 0000200000000240 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ff28820e990 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff2883a5fa0 R14: 00007ff2883a5fa0 R15: 0000000000000004
 </TASK>

report is corrupted, running repro again
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 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, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000))
timer_settime(0x0, 0x0, &(0x7f0000000240)={{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: 	1-...!: (10499 ticks this GP) idle=b854/1/0x4000000000000000 softirq=10607/10607 fqs=6
	(t=10500 jiffies g=10421 q=361 ncpus=2)
rcu: rcu_preempt kthread starved for 10488 jiffies! g10421 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:26712 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 schedule+0xbf/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4435 Comm: syz.2.18 Not tainted 6.1.134-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__remove_hrtimer kernel/time/hrtimer.c:-1 [inline]
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1671 [inline]
RIP: 0010:__hrtimer_run_queues+0x3f8/0xe50 kernel/time/hrtimer.c:1755
Code: 04 3e 84 c0 0f 85 e8 04 00 00 c6 02 00 80 e3 01 0f b6 db 31 ff 89 de e8 c6 de 10 00 84 db 75 0a e8 5d dc 10 00 e9 87 00 00 00 <48> 8b bc 24 88 00 00 00 48 8b 34 24 e8 07 0b 32 09 84 c0 74 07 e8
RSP: 0018:ffffc90000007d60 EFLAGS: 00000002
RAX: 0000000000010000 RBX: 0000000000000001 RCX: ffff88807d179dc0
RDX: ffff88807d179dc0 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000007ea8 R08: ffffffff8179cdea R09: fffffbfff1d417ce
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000002f319c2aad
R13: ffff8880b8e2a4c0 R14: ffff8880b8e2a4c0 R15: dffffc0000000000
FS:  0000555594994500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2be5ffff CR3: 000000005e18b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1817
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: d1 83 f5 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 5e aa ae f6 48 89 df e8 c6 e8 af f6 e8 81 3a d5 f6 fb bf 01 00 00 00 <e8> d6 68 a2 f6 65 8b 05 97 3e 46 75 85 c0 74 02 5b c3 e8 34 62 44
RSP: 0018:ffffc90003397b30 EFLAGS: 00000286
RAX: 02d4e58a707c0300 RBX: ffff888030c98940 RCX: ffffffff973c3103
RDX: dffffc0000000000 RSI: ffffffff8b0c1ec0 RDI: 0000000000000001
RBP: ffffc90003397c70 R08: dffffc0000000000 R09: ffffed1006193129
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff1100619317b
R13: 0000000004000000 R14: 0000000000000011 R15: ffff888030c98bd8
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x151f/0x17a0 kernel/signal.c:2874
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f222bf8d169
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:00007ffe6ad469b8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f222c1a5fa0 RCX: 00007f222bf8d169
RDX: 0000200000000240 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f222c00e990 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f222c1a5fa0 R14: 00007f222c1a5fa0 R15: 0000000000000004
 </TASK>
CPU: 1 PID: 4434 Comm: syz.1.21 Not tainted 6.1.134-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: d1 83 f5 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 5e aa ae f6 48 89 df e8 c6 e8 af f6 e8 81 3a d5 f6 fb bf 01 00 00 00 <e8> d6 68 a2 f6 65 8b 05 97 3e 46 75 85 c0 74 02 5b c3 e8 34 62 44
RSP: 0018:ffffc900015c7b30 EFLAGS: 00000286
RAX: 76e5c391414efc00 RBX: ffff88802fb71280 RCX: ffffffff973c3103
RDX: dffffc0000000000 RSI: ffffffff8b0c1ec0 RDI: 0000000000000001
RBP: ffffc900015c7c70 R08: dffffc0000000000 R09: ffffed1005f6e251
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff11005f6e2a3
R13: 0000000004000000 R14: 0000000000000011 R15: ffff88802fb71518
FS:  000055558512e500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3375ffff CR3: 000000005a79e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x151f/0x17a0 kernel/signal.c:2874
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f641cd8d169
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:00007ffdfbc36068 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000017c95 RCX: 00007f641cd8d169
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 00000004fbc3635f
R10: 00007f641ca00000 R11: 0000000000000246 R12: 00007f641cfa5fac
R13: 00007f641cfa5fa0 R14: ffffffffffffffff R15: 0000000000000004
 </TASK>
sched: RT throttling activated