rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1):
P5832/1:b..l
rcu: (detected by 1, t=10506 jiffies, g=48145, q=487 ncpus=2)
task:udevd state:R
running task stack:23288 pid:5832 tgid:5832 ppid:5199 task_flags:0x400140 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190
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:on_stack arch/x86/include/asm/stacktrace.h:55 [inline]
RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline]
RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline]
RIP: 0010:unwind_next_frame+0xabc/0x2390 arch/x86/kernel/unwind_orc.c:585
Code: 76 01 83 e6 07 83 fe 04 4c 89 64 24 10 0f 84 49 04 00 00 83 fe 03 0f 84 f3 01 00 00 83 fe 02 0f 85 a1 07 00 00 4c 89 7c 24 28 <4d> 8d 7e 08 4c 89 fd 48 c1 ed 03 48 b8 00 00 00 00 00 fc ff df 80
RSP: 0018:ffffc90003fff358 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff90ff57bd RCX: ffffffff904b5128
RDX: ffffffff90ff57b8 RSI: 0000000000000002 RDI: ffffffff8be24880
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8e3419e0
R10: ffffc90003fff478 R11: ffffffff81ade290 R12: ffffc90003ffff48
R13: ffffc90003fff478 R14: ffffc90003fff428 R15: 1ffffffff21feaf7
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:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5657 [inline]
__kmalloc_noprof+0x41d/0x800 mm/slub.c:5669
kmalloc_noprof include/linux/slab.h:961 [inline]
kmalloc_array_noprof include/linux/slab.h:1003 [inline]
security_inode_init_security+0xfc/0x3d0 security/security.c:1321
shmem_mknod+0x1fe/0x360 mm/shmem.c:3879
lookup_open fs/namei.c:4440 [inline]
open_last_lookups fs/namei.c:4540 [inline]
path_openat+0x18bb/0x3dd0 fs/namei.c:4784
do_filp_open+0x1fa/0x410 fs/namei.c:4814
do_sys_openat2+0x121/0x200 fs/open.c:1430
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1447
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: 0033:0x7f0dc70a7407
RSP: 002b:00007ffe56195950 EFLAGS: 00000202
ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f0dc77a6880 RCX: 00007f0dc70a7407
RDX: 00000000000a0241 RSI: 00007ffe56196610 RDI: ffffffffffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000124 R11: 0000000000000202 R12: 000055ef07566e00
R13: 00007ffe56196610 R14: 00007ffe56196210 R15: 00007ffe56195e10
rcu: rcu_preempt kthread starved for 3761 jiffies! g48145 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:27016 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
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:
CPU: 1 UID: 0 PID: 11322 Comm: syz.0.1555 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xccf/0x12b0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 1a 9a 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 c5 95 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 a9 95
RSP: 0018:ffffc9000cb4f320 EFLAGS: 00000293
RAX: ffffffff81b65de7 RBX: 1ffff110170c856d RCX: ffff88807b9cbd00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000cb4f4a0 R08: ffffffff8fc3a577 R09: 1ffffffff1f874ae
R10: dffffc0000000000 R11: fffffbfff1f874af R12: ffff8880b8642b68
R13: dffffc0000000000 R14: ffff8880b873bb00 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125aed000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fac25e9c990 CR3: 000000000e13a000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline]
flush_tlb_mm_range+0x6b1/0x1280 arch/x86/mm/tlb.c:1472
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline]
tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403
tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
free_ldt_pgtables+0x17b/0x320 arch/x86/kernel/ldt.c:411
arch_exit_mmap arch/x86/include/asm/mmu_context.h:234 [inline]
exit_mmap+0x174/0xb10 mm/mmap.c:1263
__mmput+0x118/0x430 kernel/fork.c:1173
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x658/0x2310 kernel/exit.c:959
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__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: 0033:0x7f586a98f749
Code: Unable to access opcode bytes at 0x7f586a98f71f.
RSP: 002b:00007ffd6d4e0af8 EFLAGS: 00000246
ORIG_RAX: 00000000000000ca
RAX: ffffffffffffff92 RBX: 000000000004c691 RCX: 00007f586a98f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f586abe5fac
RBP: 000000000000015e R08: 3fffffffffffffff R09: 0000000e6d4e0def
R10: 00007ffd6d4e0bf0 R11: 0000000000000246 R12: 00007f586abe5fac
R13: 00007ffd6d4e0bf0 R14: 000000000004c7ef R15: 00007ffd6d4e0c10