rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P18869/1:b..l P20202/1:b..l rcu: (detected by 0, t=10502 jiffies, g=111545, q=2048 ncpus=2) task:udevd state:R running task stack:25976 pid:20202 tgid:20202 ppid:5187 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_release+0x183/0x2d0 kernel/locking/lockdep.c:5893 Code: 0f c1 05 58 a3 18 12 83 f8 01 0f 85 03 01 00 00 9c 58 f6 c4 02 0f 85 ee 00 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 ed 5b 18 12 0f 85 32 01 00 00 48 83 c4 18 5b 41 5c 41 RSP: 0018:ffffc9000d0a7478 EFLAGS: 00000206 RAX: a042f0215c80e300 RBX: ffffffff8e3c9620 RCX: ffffc9000d0a7484 RDX: 0000000000000001 RSI: ffffffff8daa5c73 RDI: ffffffff8bf2a800 RBP: 0000000000000001 R08: 0000000000000001 R09: 00000000c61861bc R10: 0000000000000002 R11: 00000000000144a8 R12: ffffffff816cb9a4 R13: 0000000000000206 R14: ffff8880752a4980 R15: 0000000000000002 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:897 [inline] class_rcu_destructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0x3f9/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6668 [inline] kfree+0x2f8/0x6e0 mm/slub.c:6876 simple_xattr_free fs/xattr.c:1213 [inline] simple_xattrs_free+0x153/0x1e0 fs/xattr.c:1575 shmem_evict_inode+0x182/0xbe0 mm/shmem.c:1400 evict+0x3c2/0xad0 fs/inode.c:837 iput_final fs/inode.c:1951 [inline] iput.part.0+0x621/0x1190 fs/inode.c:2003 iput+0x35/0x40 fs/inode.c:1966 dentry_unlink_inode+0x29c/0x480 fs/dcache.c:467 __dentry_kill+0x1d0/0x600 fs/dcache.c:670 finish_dput+0x76/0x480 fs/dcache.c:879 dput.part.0+0x451/0x570 fs/dcache.c:928 dput+0x1f/0x30 fs/dcache.c:920 end_renaming fs/namei.c:4052 [inline] do_renameat2+0x7c8/0x9b0 fs/namei.c:6049 __do_sys_rename fs/namei.c:6090 [inline] __se_sys_rename fs/namei.c:6088 [inline] __x64_sys_rename+0x7d/0xa0 fs/namei.c:6088 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff390e7acc7 RSP: 002b:00007fff48092888 EFLAGS: 00000202 ORIG_RAX: 0000000000000052 RAX: ffffffffffffffda RBX: 0000561a43c281e0 RCX: 00007ff390e7acc7 RDX: 0000561a439d6010 RSI: 00007fff480928a0 RDI: 00007fff48092ca0 RBP: 0000561a439d9080 R08: 00000000000001e0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff480928a0 R13: 00007fff48092ca0 R14: 0000000000000000 R15: 0000561a43c22410 task:udevd state:R running task stack:25544 pid:18869 tgid:18869 ppid:5187 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:selinux_inode_permission+0x31/0x1190 security/selinux/hooks.c:3218 Code: 56 41 55 41 54 55 48 bd 00 00 00 00 00 fc ff df 53 65 48 8b 1d 08 4c 51 0f 48 81 ec d0 00 00 00 48 8d 44 24 50 48 89 7c 24 08 <48> c1 e8 03 89 34 24 48 89 44 24 10 48 01 e8 48 c7 44 24 50 b3 8a RSP: 0018:ffffc90002eb78b8 EFLAGS: 00000286 RAX: ffffc90002eb7908 RBX: ffff888029fc8000 RCX: ffffffff845c96e3 RDX: ffff888029fc8000 RSI: 0000000000000081 RDI: ffff8881493c8c38 RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: ffff888029fc8b30 R12: 0000000000000081 R13: 0000000000000001 R14: ffff888034c55521 R15: ffffc90002eb7b30 security_inode_permission+0xda/0x260 security/security.c:1816 lookup_inode_permission_may_exec fs/namei.c:641 [inline] may_lookup fs/namei.c:1900 [inline] link_path_walk+0x2a5/0x1c70 fs/namei.c:2537 path_lookupat+0x74/0xc40 fs/namei.c:2745 filename_lookup+0x224/0x5f0 fs/namei.c:2775 vfs_statx+0x101/0x3f0 fs/stat.c:353 vfs_fstatat+0x7b/0xf0 fs/stat.c:375 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff390f11b0a RSP: 002b:00007fff4808ce78 EFLAGS: 00000202 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 0000561a43c30811 RCX: 00007ff390f11b0a RDX: 00007fff4808ce80 RSI: 00007fff4808cf10 RDI: 00000000ffffff9c RBP: 0000561a43c180c0 R08: 0000561a43c30811 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000202 R12: 0000561a43c181b0 R13: 00007fff4808cf10 R14: 0000561a14f81ca4 R15: 0000561a14f81bcc rcu: rcu_preempt kthread starved for 10572 jiffies! g111545 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:27936 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 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: 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 10/25/2025 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 26 60 02 c3 cc cc cc cc 0f 1f 00 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 d9 12 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0000:ffffc90000197de8 EFLAGS: 000002c6 RAX: 00000000053b7c89 RBX: 0000000000000001 RCX: ffffffff8b7786d9 RDX: 0000000000000000 RSI: ffffffff8dacbd07 RDI: ffffffff8bf2a800 RBP: ffffed1003b56498 R08: 0000000000000001 R09: ffffed10170a673d R10: ffff8880b85339eb R11: ffff88801dab2ff0 R12: 0000000000000001 R13: ffff88801dab24c0 R14: ffffffff908880d0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881249fb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c25aa1c CR3: 0000000033834000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x38d/0x510 kernel/sched/idle.c:332 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x148