Extracting prog: 6m27.472139325s Minimizing prog: 1h14m48.27031176s Simplifying prog options: 9m35.011040303s Extracting C: 5m13.486999799s 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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in rtnl_newlink single: successfully extracted reproducer found reproducer with 6 syscalls minimizing guilty program testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) program did not crash testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m40.37238639s, {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-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, 0x0, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, 0x0) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, 0x0, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, 0x0) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) 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=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-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=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in corrupted a never seen crash title: INFO: rcu detected stall in corrupted, ignore testing program (duration=6m40.37238639s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program did not crash testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in inet_rtm_newaddr validation run: crashed=true testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in corrupted validation run: crashed=true testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in corrupted validation run: crashed=true reproducing took 1h46m9.080710383s repro crashed as (corrupted=true): rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=12949, q=656 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294964206-4294953704), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g12949 f0x2 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:27416 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5257 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6864 __schedule_loop kernel/sched/core.c:6946 [inline] schedule+0x165/0x360 kernel/sched/core.c:6961 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6642 Comm: syz.2.297 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x70 kernel/kcov.c:217 Code: 08 d0 c1 92 65 8b 15 e8 dc ff 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 6c 16 00 00 00 74 2c 8b 91 48 16 00 00 <83> fa 02 75 21 48 8b 91 50 16 00 00 48 8b 32 48 8d 7e 01 8b 89 4c RSP: 0018:ffffc9000bab7d18 EFLAGS: 00000246 RAX: ffffffff8169ee6a RBX: ffff88802edc8000 RCX: ffff88802edc8000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffc9000bab79cf R09: 1ffff92001756f39 R10: dffffc0000000000 R11: fffff52001756f3a R12: ffff88802edc99c0 R13: dffffc0000000000 R14: ffff88802edc802c R15: 1ffff11005db9005 FS: 00007f4d9b7dd6c0(0000) GS:ffff888125b03000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055557add37d0 CR3: 00000000765b8000 CR4: 00000000003526f0 Call Trace: fpu__clear_user_states+0x7a/0x420 arch/x86/kernel/fpu/core.c:812 handle_signal arch/x86/kernel/signal.c:310 [inline] arch_do_signal_or_restart+0x44c/0x7a0 arch/x86/kernel/signal.c:339 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4d9c04d6e0 Code: 44 24 20 0f 29 44 24 30 0f 29 44 24 40 48 8b 44 24 08 ff d0 48 83 c4 50 31 c0 5b 5d 41 5c 41 5d 41 5e c3 0f 1f 80 00 00 00 00 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 c3 66 66 2e 0f 1f RSP: 002b:00007f4d9b7dcb38 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f4d9c3e6098 RCX: 00007f4d9c18f749 RDX: 00007f4d9b7dcb40 RSI: 00007f4d9b7dcc70 RDI: 0000000000000011 RBP: 00007f4d9c3e6090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4d9c3e6128 R14: 00007ffcc685f2a0 R15: 00007ffcc685f388 report is corrupted, running repro again testing program (duration=6m40.37238639s, {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}}): socket$nl_generic-prlimit64-sched_setscheduler-prctl$PR_SCHED_CORE-timer_create-timer_settime detailed listing: executing program 0: socket$nl_generic(0x10, 0x3, 0x10) prlimit64(0x0, 0xe, &(0x7f0000000140)={0x7, 0x100}, 0x0) sched_setscheduler(0x0, 0x2, &(0x7f0000000200)=0x7) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0) timer_create(0x0, &(0x7f0000000080)={0x0, 0x11}, &(0x7f0000000000)) timer_settime(0x0, 0x0, &(0x7f0000000180)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in sys_symlinkat final repro crashed as (corrupted=false): rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7401/1:b..l rcu: (detected by 0, t=10502 jiffies, g=15197, q=504 ncpus=2) task:syz-executor state:R running task stack:27832 pid:7401 tgid:7401 ppid:5961 task_flags:0x400040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5257 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6864 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7191 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x16c/0x340 kernel/locking/lockdep.c:5872 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 74 17 23 11 <48> 3b 44 24 58 0f 85 e5 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000bd6f618 EFLAGS: 00000206 RAX: 998a31ae79591c00 RBX: 0000000000000000 RCX: 998a31ae79591c00 RDX: 00000000ddafba15 RSI: ffffffff8dc7e873 RDI: ffffffff8be1e760 RBP: ffffffff81747f85 R08: ffffffff81747f85 R09: ffffffff8e3419e0 R10: ffffc9000bd6f7d8 R11: ffffffff81ade230 R12: 0000000000000002 R13: ffffffff8e3419e0 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4948 [inline] slab_alloc_node mm/slub.c:5258 [inline] kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5265 lsm_inode_alloc security/security.c:228 [inline] security_inode_alloc+0x39/0x330 security/security.c:1189 inode_init_always_gfp+0x9ed/0xdc0 fs/inode.c:306 inode_init_always include/linux/fs.h:2883 [inline] alloc_inode+0x82/0x1b0 fs/inode.c:353 new_inode+0x22/0x170 fs/inode.c:1175 __shmem_get_inode mm/shmem.c:3068 [inline] shmem_get_inode+0x347/0xe60 mm/shmem.c:3142 shmem_symlink+0xa3/0x470 mm/shmem.c:4107 vfs_symlink+0x294/0x2d0 fs/namei.c:5514 do_symlinkat+0x1f5/0x3c0 fs/namei.c:5541 __do_sys_symlinkat fs/namei.c:5562 [inline] __se_sys_symlinkat fs/namei.c:5559 [inline] __x64_sys_symlinkat+0x95/0xb0 fs/namei.c:5559 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fef6e18ecc7 RSP: 002b:00007ffc0b934368 EFLAGS: 00000202 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fef6e18ecc7 RDX: 00007fef6e2158e4 RSI: 00000000ffffff9c RDI: 00007ffc0b934400 RBP: 00007ffc0b9343ac R08: 0000000000000013 R09: 00007ffc0b9340b7 R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000000a4 R13: 00000000000927c0 R14: 000000000002808d R15: 00007ffc0b934400 rcu: rcu_preempt kthread starved for 10531 jiffies! g15197 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:27784 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5257 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6864 __schedule_loop kernel/sched/core.c:6946 [inline] schedule+0x165/0x360 kernel/sched/core.c:6961 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 7399 Comm: syz.0.671 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline] RIP: 0010:__local_bh_disable_ip+0xfe/0x190 kernel/softirq.c:395 Code: fb 65 8b 05 f4 13 3c 11 25 ff ff ff 7f 39 d8 75 42 48 8b 5d 08 48 89 df e8 9f 8a 19 00 85 c0 74 09 31 db 31 ff e8 92 8a 19 00 <65> 4c 8b 34 25 08 d0 c1 92 49 81 c6 20 15 00 00 4c 89 f0 48 c1 e8 RSP: 0018:ffffc9000c447c60 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff8169ee7f RCX: 00000000040a6300 RDX: 0000000000000000 RSI: 0000000000000200 RDI: ffffffff8169ee7f RBP: ffffc9000c447d10 R08: ffffc9000c4479cf R09: 1ffff92001888f39 R10: dffffc0000000000 R11: fffff52001888f3a R12: 1ffff92001888f8c R13: dffffc0000000000 R14: 0000000000000246 R15: dffffc0000000000 FS: 00007f6e08e756c0(0000) GS:ffff888125b03000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f91d0d26830 CR3: 0000000021ec8000 CR4: 00000000003526f0 Call Trace: local_bh_disable include/linux/bottom_half.h:20 [inline] fpregs_lock arch/x86/include/asm/fpu/api.h:69 [inline] fpu__clear_user_states+0x8f/0x420 arch/x86/kernel/fpu/core.c:814 handle_signal arch/x86/kernel/signal.c:310 [inline] arch_do_signal_or_restart+0x44c/0x7a0 arch/x86/kernel/signal.c:339 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6e07e4d6e0 Code: 44 24 20 0f 29 44 24 30 0f 29 44 24 40 48 8b 44 24 08 ff d0 48 83 c4 50 31 c0 5b 5d 41 5c 41 5d 41 5e c3 0f 1f 80 00 00 00 00 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 c3 66 66 2e 0f 1f RSP: 002b:00007f6e08e74b38 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f6e081e5fa8 RCX: 00007f6e07f8f749 RDX: 00007f6e08e74b40 RSI: 00007f6e08e74c70 RDI: 0000000000000011 RBP: 00007f6e081e5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6e081e6038 R14: 00007fff3d549c50 R15: 00007fff3d549d38