rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=2f34/0/0x1 softirq=43172/43172 fqs=1 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P11290/1:b..l rcu: (detected by 0, t=10502 jiffies, g=39453, q=56 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-syzkaller-12063-g37816488247d #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:timerqueue_add+0x28f/0x330 lib/timerqueue.c:40 Code: 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 69 48 8b 04 24 48 89 ef 48 89 68 08 48 89 c6 e8 f4 85 ff ff 48 85 ed <41> 0f 95 c6 e9 25 ff ff ff e8 33 b7 2c f6 90 0f 0b 90 e9 ab fd ff RSP: 0018:ffffc90000a08e00 EFLAGS: 00000082 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff8b8ed998 RDX: 1ffff1100f850e68 RSI: ffff8880b8527dd0 RDI: ffff88807c287340 RBP: ffff88807c287340 R08: 0000000000000006 R09: ffff88807c287340 R10: ffff88807c287340 R11: ffffffff9b0d1428 R12: ffff8880b8527c80 R13: 0000000000000000 R14: ffff88807c287340 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8881247c4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000397030 CR3: 000000005b3d8000 CR4: 00000000003526f0 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1778 [inline] __hrtimer_run_queues+0x8ff/0xad0 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x10b/0x3f0 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 2c 63 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 f3 52 17 00 fb f4 4c 0d 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197df8 EFLAGS: 000002c2 RAX: 0000000000d26ddf RBX: 0000000000000001 RCX: ffffffff8b92bc29 RDX: 0000000000000000 RSI: ffffffff8de4e889 RDI: ffffffff8c161180 RBP: ffffed1003c5d488 R08: 0000000000000001 R09: ffffed10170a6655 R10: ffff8880b85332ab R11: 0000000000000000 R12: 0000000000000001 R13: ffff88801e2ea440 R14: ffffffff90ab0090 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148 task:syz-executor state:R running task stack:28952 pid:11290 tgid:11290 ppid:5841 task_flags:0x400040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288 irqentry_exit+0x36/0x90 kernel/entry/common.c:197 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872 Code: f7 3d 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 62 37 13 0f 0f 82 74 02 00 00 8b 35 2a 69 13 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 b9 f6 3d 12 0f 85 c7 02 00 00 48 83 c4 RSP: 0018:ffffc9001dcb7910 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e5c1160 RCX: 00000000b315e02b RDX: 0000000000000000 RSI: ffffffff8de29498 RDI: ffffffff8c161180 RBP: 0000000000000002 R08: 3dcec2d5cd23f461 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] xa_load+0xcd/0x2c0 lib/xarray.c:1617 memcg_list_lru_allocated mm/list_lru.c:510 [inline] memcg_list_lru_alloc+0x1c0/0x740 mm/list_lru.c:521 __memcg_slab_post_alloc_hook+0x133/0x960 mm/memcontrol.c:3163 memcg_slab_post_alloc_hook mm/slub.c:2216 [inline] slab_post_alloc_hook mm/slub.c:4190 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_lru_noprof+0x30f/0x3b0 mm/slub.c:4248 shmem_alloc_inode+0x25/0x50 mm/shmem.c:5211 alloc_inode+0x64/0x240 fs/inode.c:346 new_inode+0x22/0x1c0 fs/inode.c:1145 __shmem_get_inode mm/shmem.c:3110 [inline] shmem_get_inode+0x19a/0xfb0 mm/shmem.c:3184 shmem_symlink+0xf8/0x9f0 mm/shmem.c:4158 vfs_symlink fs/namei.c:4730 [inline] vfs_symlink+0x403/0x680 fs/namei.c:4714 do_symlinkat+0x261/0x310 fs/namei.c:4756 __do_sys_symlinkat fs/namei.c:4772 [inline] __se_sys_symlinkat fs/namei.c:4769 [inline] __x64_sys_symlinkat+0x93/0xc0 fs/namei.c:4769 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcad658e167 RSP: 002b:00007fff34530408 EFLAGS: 00000202 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fcad658e167 RDX: 00007fcad66136cd RSI: 00000000ffffff9c RDI: 00007fff345304a0 RBP: 00007fff3453044c R08: 0000000000000013 R09: 00007fff34530157 R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000016d R13: 00000000000927c0 R14: 0000000000054572 R15: 00007fff345304a0 rcu: rcu_preempt kthread starved for 10500 jiffies! g39453 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2285 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.16.0-syzkaller-12063-g37816488247d #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 2c 63 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 f3 52 17 00 fb f4 4c 0d 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff8e207e08 EFLAGS: 000002c2 RAX: 0000000000d6bdcb RBX: 0000000000000000 RCX: ffffffff8b92bc29 RDX: 0000000000000000 RSI: ffffffff8de4e889 RDI: ffffffff8c161180 RBP: fffffbfff1c52ef8 R08: 0000000000000001 R09: ffffed1017086655 R10: ffff8880b84332ab R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff8e2977c0 R14: ffffffff90ab0090 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881246c4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000404030 CR3: 0000000074af4000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 rest_init+0x16b/0x2b0 init/main.c:744 start_kernel+0x3ee/0x4d0 init/main.c:1097 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x148