rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=262c/1/0x4000000000000000 softirq=168133/168135 fqs=4
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10878/1:b..l P24838/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=193197, q=580 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 27513 Comm: syz.2.5340 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:num_possible_cpus include/linux/cpumask.h:1222 [inline]
RIP: 0010:mm_get_cid kernel/sched/sched.h:3880 [inline]
RIP: 0010:sched_mm_cid_fork+0x661/0x10e0 kernel/sched/core.c:10953
Code: 00 49 c7 c4 b8 2e 26 8e 49 c1 ec 03 41 bd 00 00 00 80 eb 0a 89 e8 f7 d8 0f 81 09 fe ff ff f3 90 48 b8 00 00 00 00 00 fc ff df <41> 0f b6 04 04 84 c0 75 40 44 8b 35 d7 73 91 0c 48 89 df 4c 89 f6
RSP: 0018:ffffc90004127c48 EFLAGS: 00000887
RAX: dffffc0000000000 RBX: ffff888034c497d0 RCX: 0000000080000001
RDX: dffffc0000000000 RSI: 0000000000000002 RDI: ffff888034c497d0
RBP: 0000000080000000 R08: 1ffff110069891a9 R09: 0000000000000000
R10: ffff888034c48e8c R11: fffff52000824f78 R12: 1ffffffff1c4c5d7
R13: 0000000080000000 R14: 0000000000000002 R15: ffff888034c48c40
FS: 00007f474d9f96c0(0000) GS:ffff888125293000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3170aff8 CR3: 0000000021b94000 CR4: 0000000000350ef0
Call Trace:
bprm_execve+0xdb7/0x1440 fs/exec.c:1771
do_execveat_common+0x50d/0x690 fs/exec.c:1846
__do_sys_execveat fs/exec.c:1941 [inline]
__se_sys_execveat fs/exec.c:1934 [inline]
__x64_sys_execveat+0xc7/0xf0 fs/exec.c:1934
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f474cb9cdd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f474d9f9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000142
RAX: ffffffffffffffda RBX: 00007f474ce15fa0 RCX: 00007f474cb9cdd9
RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000005
RBP: 00007f474cc32d69 R08: 0000000000001000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f474ce16038 R14: 00007f474ce15fa0 R15: 00007ffe9cbeda48
task:syz-executor state:R running task stack:22408 pid:24838 tgid:24838 ppid:1 task_flags:0x40054c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7188
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7369
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:190
spin_unlock include/linux/spinlock.h:390 [inline]
zap_pte_range mm/memory.c:1948 [inline]
zap_pmd_range mm/memory.c:2004 [inline]
zap_pud_range mm/memory.c:2032 [inline]
zap_p4d_range mm/memory.c:2053 [inline]
__zap_vma_range+0x3d17/0x4b40 mm/memory.c:2093
unmap_vmas+0x379/0x530 mm/memory.c:2162
exit_mmap+0x280/0x9e0 mm/mmap.c:1300
__mmput+0x118/0x430 kernel/fork.c:1178
exit_mm+0x18e/0x250 kernel/exit.c:581
do_exit+0x6a2/0x22c0 kernel/exit.c:963
do_group_exit+0x21b/0x2d0 kernel/exit.c:1117
get_signal+0x1284/0x1330 kernel/signal.c:3037
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4dd239e647
RSP: 002b:00007fff8d70a438 EFLAGS: 00000202 ORIG_RAX: 0000000000000029
RAX: 0000000000000003 RBX: 0000000000000003 RCX: 00007f4dd239e647
RDX: 0000000000000006 RSI: 0000000000000001 RDI: 0000000000000002
RBP: 00007fff8d70ab6c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007f4dd25eafc0
R13: 00005555711609f0 R14: 00000000001b39c0 R15: 00007f4dd25ed180
task:udevd state:R running task stack:23288 pid:10878 tgid:10878 ppid:4985 task_flags:0x400140 flags:0x00080800
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7188
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7512
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline]
irqentry_exit+0x14f/0x730 kernel/entry/common.c:164
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:debug_lockdep_rcu_enabled+0x16/0x40 kernel/rcu/update.c:320
Code: cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 31 c0 83 3d 63 bf 88 04 00 74 1d 83 3d 1a f1 88 04 00 <74> 14 65 48 8b 0d 58 f5 90 07 31 c0 83 b9 8c 0b 00 00 00 0f 94 c0
RSP: 0018:ffffc90004b47110 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffffff81aeae8d RCX: 0000000000000046
RDX: 000000005a44979c RSI: ffffffff8e2171d5 RDI: ffffffff8c28ab60
RBP: dffffc0000000000 R08: ffffffff8176e256 R09: ffffffff8e95cd60
R10: dffffc0000000000 R11: ffffffff81b0d880 R12: ffffc90004b47220
R13: 1ffff92000968e3d R14: ffffc90004b471e8 R15: ffffffff8176e256
rcu_read_lock include/linux/rcupdate.h:839 [inline]
class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
unwind_next_frame+0xcc/0x2550 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1402 [inline]
free_unref_folios+0xcec/0x1480 mm/page_alloc.c:3004
folios_put_refs+0x9ff/0xb40 mm/swap.c:1008
folio_batch_release include/linux/folio_batch.h:101 [inline]
shmem_undo_range+0x52c/0x1660 mm/shmem.c:1149
shmem_truncate_range mm/shmem.c:1277 [inline]
shmem_evict_inode+0x289/0xae0 mm/shmem.c:1407
evict+0x61e/0xb10 fs/inode.c:841
__dentry_kill+0x1a2/0x690 fs/dcache.c:718
finish_dput+0xc9/0x480 fs/dcache.c:927
__fput+0x691/0xa60 fs/file_table.c:518
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4b6f8a7407
RSP: 002b:00007ffdf9ac6e40 EFLAGS: 00000202 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00007f4b6ff80880 RCX: 00007f4b6f8a7407
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000008
RBP: 00007f4b6ff806e8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002
R13: 0000559811ed7190 R14: 0000000000000008 R15: 0000559811ee1e00
rcu: rcu_preempt kthread starved for 10494 jiffies! g193197 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:27536 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 5b 7e 02 e9 fe 6f 68 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 13 91 21 00 fb f4 d7 6f 68 f5 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 00000242
RAX: 0000000003ce1725 RBX: ffffffff819a815a RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8dfa3d4e RDI: ffffffff8c28ab60
RBP: ffffc90000197f10 R08: ffff8880b87339db R09: 1ffff110170e673b
R10: dffffc0000000000 R11: ffffed10170e673c R12: 0000000000000001
R13: 1ffff11003b54000 R14: 0000000000000001 R15: 1ffff11003b54000
FS: 0000000000000000(0000) GS:ffff888125393000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056150f6fa950 CR3: 0000000032182000 CR4: 0000000000350ef0
Call Trace:
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x36a/0x5f0 kernel/sched/idle.c:352
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147