Extracting prog: 4m3.58521226s Minimizing prog: 54m58.862899278s Simplifying prog options: 10m2.528669664s Extracting C: 2m25.026162472s 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, 0x2, &(0x7f0000000200)=0x4) 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, 0x2, &(0x7f0000000200)=0x4) 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, 0x2, &(0x7f0000000200)=0x4) 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, 0x2, &(0x7f0000000200)=0x4) 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, 0x2, &(0x7f0000000200)=0x4) 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, 0x2, 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, 0x2, &(0x7f0000000200)=0x4) 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, 0x2, &(0x7f0000000200)=0x4) 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, 0x2, &(0x7f0000000200)=0x4) 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, 0x2, &(0x7f0000000200)=0x4) 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, 0x2, &(0x7f0000000200)=0x4) 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, 0x2, &(0x7f0000000200)=0x4) timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in kernfs_fop_write_iter 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, 0x2, &(0x7f0000000200)=0x4) 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, 0x2, &(0x7f0000000200)=0x4) timer_create(0x0, &(0x7f0000000680)={0x0, 0x21}, &(0x7f0000000100)) timer_settime(0x0, 0x0, &(0x7f000006b000)={{0x0, 0x8}, {0x0, 0x9}}, 0x0) program crashed: INFO: rcu detected stall in do_mas_munmap validation run: crashed=true reproducing took 1h21m9.93758316s 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): P4534/1:b..l (detected by 0, t=10503 jiffies, g=12169, q=563 ncpus=2) task:modprobe state:R running task stack:24336 pid:4534 ppid:4342 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5710 Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f RSP: 0018:ffffc900040c7178 EFLAGS: 00000206 RAX: f99a529c8d04c200 RBX: ffff88802c669dc0 RCX: f99a529c8d04c200 RDX: 0000000000000000 RSI: ffffffff8a8c2220 RDI: ffffffff8adf0d20 RBP: 0000000000000001 R08: ffff88802c669dc0 R09: 0000000000000003 R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000246 R14: ffff888018add3d8 R15: ffff88802c66a8a0 lock_is_held include/linux/lockdep.h:283 [inline] mt_locked lib/maple_tree.c:-1 [inline] mt_slot lib/maple_tree.c:816 [inline] mas_slot lib/maple_tree.c:849 [inline] mt_validate_nulls lib/maple_tree.c:7193 [inline] mt_validate+0x43d1/0x4cb0 lib/maple_tree.c:7249 validate_mm_mt+0xe2/0x440 mm/mmap.c:295 validate_mm+0xe1/0x2e0 mm/mmap.c:332 __vma_adjust+0x1855/0x1cd0 mm/mmap.c:879 vma_adjust include/linux/mm.h:2810 [inline] __split_vma+0x3a7/0x500 mm/mmap.c:-1 do_mas_align_munmap+0x397/0x12b0 mm/mmap.c:2480 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650 __mmap_region mm/mmap.c:2698 [inline] mmap_region+0x6e0/0x1ca0 mm/mmap.c:2916 do_mmap+0x964/0xfd0 mm/mmap.c:1436 vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:520 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f758aea4242 RSP: 002b:00007fff12210fc8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f758ab8d000 RCX: 00007f758aea4242 RDX: 0000000000000005 RSI: 000000000001c000 RDI: 00007f758ab8d000 RBP: 0000000000000812 R08: 0000000000000000 R09: 0000000000008000 R10: 0000000000000812 R11: 0000000000000206 R12: 00007fff12211018 R13: 00007f758ae81ab0 R14: 00007fff12211440 R15: 00000fffe24421fc rcu: rcu_preempt kthread starved for 10531 jiffies! g12169 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:27760 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 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: 56 Comm: kworker/u4:4 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline] RIP: 0010:smp_call_function_many_cond+0xea2/0x1290 kernel/smp.c:998 Code: 00 00 00 41 8b 1f 89 de 83 e6 01 31 ff e8 e6 f6 0a 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 72 f3 0a 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 57 f3 0a RSP: 0018:ffffc90001577800 EFLAGS: 00000293 RAX: ffffffff81778139 RBX: dffffc0000000000 RCX: ffff88801eedbb80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90001577960 R08: ffffffff90af7247 R09: 1ffffffff215ee48 R10: dffffc0000000000 R11: fffffbfff215ee49 R12: 1ffff110171c8601 R13: ffff8880b8f3bbc0 R14: 0000000000000000 R15: ffff8880b8e43008 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000006b000 CR3: 000000000c88e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1165 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1574 [inline] text_poke_bp_batch+0x2b7/0x850 arch/x86/kernel/alternative.c:1774 text_poke_flush arch/x86/kernel/alternative.c:1965 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x11f/0x240 kernel/jump_label.c:207 static_key_enable+0x16/0x20 kernel/jump_label.c:220 toggle_allocation_gate+0xba/0x470 mm/kfence/core.c:821 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 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): P4534/1:b..l (detected by 0, t=10503 jiffies, g=12169, q=563 ncpus=2) task:modprobe state:R running task stack:24336 pid:4534 ppid:4342 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5710 Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f RSP: 0018:ffffc900040c7178 EFLAGS: 00000206 RAX: f99a529c8d04c200 RBX: ffff88802c669dc0 RCX: f99a529c8d04c200 RDX: 0000000000000000 RSI: ffffffff8a8c2220 RDI: ffffffff8adf0d20 RBP: 0000000000000001 R08: ffff88802c669dc0 R09: 0000000000000003 R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000246 R14: ffff888018add3d8 R15: ffff88802c66a8a0 lock_is_held include/linux/lockdep.h:283 [inline] mt_locked lib/maple_tree.c:-1 [inline] mt_slot lib/maple_tree.c:816 [inline] mas_slot lib/maple_tree.c:849 [inline] mt_validate_nulls lib/maple_tree.c:7193 [inline] mt_validate+0x43d1/0x4cb0 lib/maple_tree.c:7249 validate_mm_mt+0xe2/0x440 mm/mmap.c:295 validate_mm+0xe1/0x2e0 mm/mmap.c:332 __vma_adjust+0x1855/0x1cd0 mm/mmap.c:879 vma_adjust include/linux/mm.h:2810 [inline] __split_vma+0x3a7/0x500 mm/mmap.c:-1 do_mas_align_munmap+0x397/0x12b0 mm/mmap.c:2480 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650 __mmap_region mm/mmap.c:2698 [inline] mmap_region+0x6e0/0x1ca0 mm/mmap.c:2916 do_mmap+0x964/0xfd0 mm/mmap.c:1436 vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:520 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f758aea4242 RSP: 002b:00007fff12210fc8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f758ab8d000 RCX: 00007f758aea4242 RDX: 0000000000000005 RSI: 000000000001c000 RDI: 00007f758ab8d000 RBP: 0000000000000812 R08: 0000000000000000 R09: 0000000000008000 R10: 0000000000000812 R11: 0000000000000206 R12: 00007fff12211018 R13: 00007f758ae81ab0 R14: 00007fff12211440 R15: 00000fffe24421fc rcu: rcu_preempt kthread starved for 10531 jiffies! g12169 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:27760 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 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: 56 Comm: kworker/u4:4 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline] RIP: 0010:smp_call_function_many_cond+0xea2/0x1290 kernel/smp.c:998 Code: 00 00 00 41 8b 1f 89 de 83 e6 01 31 ff e8 e6 f6 0a 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 72 f3 0a 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 57 f3 0a RSP: 0018:ffffc90001577800 EFLAGS: 00000293 RAX: ffffffff81778139 RBX: dffffc0000000000 RCX: ffff88801eedbb80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90001577960 R08: ffffffff90af7247 R09: 1ffffffff215ee48 R10: dffffc0000000000 R11: fffffbfff215ee49 R12: 1ffff110171c8601 R13: ffff8880b8f3bbc0 R14: 0000000000000000 R15: ffff8880b8e43008 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000006b000 CR3: 000000000c88e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1165 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1574 [inline] text_poke_bp_batch+0x2b7/0x850 arch/x86/kernel/alternative.c:1774 text_poke_flush arch/x86/kernel/alternative.c:1965 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x11f/0x240 kernel/jump_label.c:207 static_key_enable+0x16/0x20 kernel/jump_label.c:220 toggle_allocation_gate+0xba/0x470 mm/kfence/core.c:821 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295