Extracting prog: 7m47.223322683s
Minimizing prog: 54m53.531235439s
Simplifying prog options: 8m40.552352581s
Extracting C: 2m23.432399046s
Simplifying C: 0s


extracting reproducer from 1 programs
testing a last program of every proc
single: executing 1 programs separately with timeout 30s
testing program (duration=30s, {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 did not crash
program did not crash
single: failed to extract reproducer
single: executing 1 programs separately with timeout 1m40s
testing program (duration=1m40s, {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 did not crash
single: failed to extract reproducer
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 corrupted
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 syscall_exit_to_user_mode
a never seen crash title: INFO: rcu detected stall in syscall_exit_to_user_mode, 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 corrupted
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 1h21m8.595046683s
repro crashed as (corrupted=true):
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10499 ticks this GP) idle=eeb/1/0x4000000000000000 softirq=6602/6611 fqs=8 
	(t=10500 jiffies g=8065 q=433)
rcu: rcu_preempt kthread starved for 10482 jiffies! g8065 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:28064 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4402 Comm: syz.1.25 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:205
Code: 84 00 00 00 00 00 53 48 89 fb e8 17 00 00 00 48 8b 3d d0 6b f1 0b 48 89 de 5b e9 d7 9e 43 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d a4 a3 8a 7e 65 8b 15 a5 a3 8a 7e 81 e2 00 01 ff 00 74
RSP: 0018:ffffc9000403fee0 EFLAGS: 00000046
RAX: ffffffff817de860 RBX: ffffffff89a1f35b RCX: ffff88801d818000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000403ff48 R08: dffffc0000000000 R09: ffffed1003b03001
R10: ffffed1003b03001 R11: 1ffff11003b03000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffc9000403ff58 R15: 0000000000000027
FS:  00007f75547856c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 00000000740c4000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
 static_key_false include/linux/jump_label.h:212 [inline]
 trace_irq_enable include/trace/events/preemptirq.h:40 [inline]
 trace_hardirqs_on_prepare+0x60/0x1f0 kernel/trace/trace_preemptirq.c:32
 __exit_to_user_mode kernel/entry/common.c:132 [inline]
 syscall_exit_to_user_mode+0x1b/0x40 kernel/entry/common.c:309
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f755510d5e7
Code: 0b e9 68 fe ff ff 48 83 c4 18 48 8d 3d b2 62 d9 00 5b 5d 41 5c 41 5d 41 5e 41 5f e9 23 f8 fb ff 0f 1f 00 b8 27 00 00 00 0f 05 <c3> 0f 1f 84 00 00 00 00 00 b8 6e 00 00 00 0f 05 c3 0f 1f 84 00 00
RSP: 002b:00007f7554784b08 EFLAGS: 00000202 ORIG_RAX: 0000000000000027
RAX: 0000000000000005 RBX: 00007f7554784c70 RCX: 00007f755510d5e7
RDX: 00007f7554784b40 RSI: 00007f7554784c70 RDI: 0000000000000021
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007f755536d038 R14: 00007fffc24b67a0 R15: 00007fffc24b6888
 </TASK>
NMI backtrace for cpu 0
CPU: 0 PID: 4399 Comm: syz.0.24 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 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+0x6d8/0x1110 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:1818
 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+0x4fe/0xc40 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1108
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0033:0x7fb772da8e80
Code: 83 c0 16 83 e0 f7 74 12 50 48 8d 3d 8a 54 08 00 e8 05 8f f8 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:00007fb7723eeb38 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007fb772fd6fa8 RCX: 00007fb772d80749
RDX: 00007fb7723eeb40 RSI: 00007fb7723eec70 RDI: 0000000000000021
RBP: 00007fb772fd6fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb772fd7038 R14: 00007fffcfc76aa0 R15: 00007fffcfc76b88
 </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 corrupted
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 corrupted
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 detected stalls on CPUs/tasks:
	(detected by 0, t=10502 jiffies, g=8597, q=512)
rcu: All QSes seen, last rcu_preempt kthread activity 10501 (4294958609-4294948108), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g8597 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:26688 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 4466 Comm: syz.2.33 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 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_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:1818
 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+0x4fe/0xc40 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f6 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 be 2b b1 f7 48 89 df e8 86 00 b2 f7 e8 21 9a d2 f7 fb bf 01 00 00 00 <e8> 56 22 a6 f7 65 8b 05 e7 1f 57 76 85 c0 74 02 5b c3 e8 f4 2a 55
RSP: 0018:ffffc900036ffb50 EFLAGS: 00000282
RAX: 6be50be1ccbc5d00 RBX: ffff88802aa9d340 RCX: 6be50be1ccbc5d00
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: 0000000000000001
RBP: ffffc900036ffcb0 R08: dffffc0000000000 R09: ffffed1005553a69
R10: ffffed1005553a69 R11: 1ffff11005553a68 R12: dffffc0000000000
R13: 0000000100000000 R14: 0000000000000000 R15: 0000000000000020
 set_current_blocked kernel/signal.c:3072 [inline]
 signal_delivered kernel/signal.c:2936 [inline]
 signal_setup_done+0x28c/0x440 kernel/signal.c:2947
 handle_signal arch/x86/kernel/signal.c:842 [inline]
 arch_do_signal_or_restart+0xf2e/0x1300 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: 0033:0x7fc8a607ae80
Code: 83 c0 16 83 e0 f7 74 12 50 48 8d 3d 8a 54 08 00 e8 05 8f f8 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:00007fc8a56c0b38 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007fc8a62a8fa8 RCX: 00007fc8a6052749
RDX: 00007fc8a56c0b40 RSI: 00007fc8a56c0c70 RDI: 0000000000000021
RBP: 00007fc8a62a8fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc8a62a9038 R14: 00007ffde9252aa0 R15: 00007ffde9252b88
 </TASK>