rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7471/1:b..l P5818/1:b..l rcu: (detected by 0, t=10502 jiffies, g=16085, q=431 ncpus=2) task:syz-executor state:R running task stack:23000 pid:5818 tgid:5818 ppid:5803 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_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:its_return_thunk+0x0/0x10 arch/x86/lib/retpoline.S:417 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 e9 4b 7d b1 f5 cc RSP: 0018:ffffc90003a3f400 EFLAGS: 00000297 RAX: 0000000000000001 RBX: ffffffff8e3c9620 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffffffff816cb681 RDI: fffffbfff1c792c4 RBP: ffffffff8e3c9620 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 00000000000a7671 R12: ffffffff816cb681 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 __kasan_check_byte+0x13/0x50 mm/kasan/common.c:572 kasan_check_byte include/linux/kasan.h:401 [inline] lock_acquire kernel/locking/lockdep.c:5842 [inline] lock_acquire+0xfc/0x330 kernel/locking/lockdep.c:5825 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xd1/0x20a0 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 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:414 kmalloc_node_noprof include/linux/slab.h:983 [inline] __get_vm_area_node+0x101/0x330 mm/vmalloc.c:3208 __vmalloc_node_range_noprof+0x247/0x16b0 mm/vmalloc.c:4011 __vmalloc_node_noprof+0xad/0xf0 mm/vmalloc.c:4111 alloc_counters net/ipv6/netfilter/ip6_tables.c:815 [inline] copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:837 [inline] get_entries net/ipv6/netfilter/ip6_tables.c:1039 [inline] do_ip6t_get_ctl+0x6b6/0xae0 net/ipv6/netfilter/ip6_tables.c:1677 nf_getsockopt+0x7c/0xe0 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x1f7/0x280 net/ipv6/ipv6_sockglue.c:1473 tcp_getsockopt+0xa1/0x100 net/ipv4/tcp.c:4834 do_sock_getsockopt+0x324/0x410 net/socket.c:2383 __sys_getsockopt+0x12f/0x260 net/socket.c:2412 __do_sys_getsockopt net/socket.c:2419 [inline] __se_sys_getsockopt net/socket.c:2416 [inline] __x64_sys_getsockopt+0xbd/0x160 net/socket.c:2416 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: 0033:0x7fb5e259148a RSP: 002b:00007ffc1420f6f8 EFLAGS: 00000212 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 00007ffc1420f780 RCX: 00007fb5e259148a RDX: 0000000000000041 RSI: 0000000000000029 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00007ffc1420f71c R09: 0079746972756365 R10: 00007ffc1420f780 R11: 0000000000000212 R12: 00007fb5e27b6a20 R13: 00007ffc1420f71c R14: 0000000000000000 R15: 00007fb5e27b7e60 task:syz.1.321 state:R running task stack:26008 pid:7471 tgid:7469 ppid:5810 task_flags:0x400040 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:trace_lock_acquire include/trace/events/lock.h:24 [inline] RIP: 0010:lock_acquire+0x4e/0x330 kernel/locking/lockdep.c:5831 Code: 48 8b 05 dd 76 17 12 48 89 44 24 30 31 c0 66 90 65 8b 05 f9 76 17 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 82 fe ed 0e <0f> 82 74 02 00 00 8b 35 1a 2f ee 0e 85 f6 0f 85 8d 00 00 00 48 8b RSP: 0018:ffffc90004fdf458 EFLAGS: 00000297 RAX: 0000000000000000 RBX: ffffffff8e3c9620 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e3c9620 RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffff8880326554b0 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] percpu_ref_get_many include/linux/percpu-refcount.h:202 [inline] percpu_ref_get include/linux/percpu-refcount.h:222 [inline] css_get include/linux/cgroup_refcnt.h:11 [inline] css_get include/linux/cgroup_refcnt.h:8 [inline] charge_memcg+0x130/0x230 mm/memcontrol.c:4732 __mem_cgroup_charge+0x2b/0x1e0 mm/memcontrol.c:4745 mem_cgroup_charge include/linux/memcontrol.h:663 [inline] shmem_alloc_and_add_folio+0x50c/0xc20 mm/shmem.c:1942 shmem_get_folio_gfp+0x67f/0x1610 mm/shmem.c:2556 shmem_fault+0x1fe/0xa00 mm/shmem.c:2757 __do_fault+0x10d/0x490 mm/memory.c:5320 do_read_fault mm/memory.c:5755 [inline] do_fault+0xae4/0x1ad0 mm/memory.c:5889 do_pte_missing mm/memory.c:4401 [inline] handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault+0x1919/0x2bb0 mm/memory.c:6411 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x54e/0x3590 mm/gup.c:1428 populate_vma_page_range+0x267/0x3f0 mm/gup.c:1860 __mm_populate+0x1d8/0x380 mm/gup.c:1963 mm_populate include/linux/mm.h:3701 [inline] vm_mmap_pgoff+0x37f/0x470 mm/util.c:586 ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:604 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82 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: 0033:0x7fa4b698f749 RSP: 002b:00007fa4b7764038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fa4b6be5fa0 RCX: 00007fa4b698f749 RDX: 0000000000000002 RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007fa4b6a13f91 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa4b6be6038 R14: 00007fa4b6be5fa0 R15: 00007ffc84071758 rcu: rcu_preempt kthread starved for 10478 jiffies! g16085 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:29112 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: CPU: 0 UID: 0 PID: 0 Comm: swapper/0 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: 06 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 59 13 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: 0018:ffffffff8e007df8 EFLAGS: 000002c6 RAX: 000000000091acdd RBX: 0000000000000000 RCX: ffffffff8b7706d9 RDX: 0000000000000000 RSI: ffffffff8dac204b RDI: ffffffff8bf24280 RBP: fffffbfff1c12f68 R08: 0000000000000001 R09: ffffed101708673d R10: ffff8880b84339eb R11: ffffffff8e098670 R12: 0000000000000000 R13: ffffffff8e097b40 R14: ffffffff9087f7d0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124909000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000021000 CR3: 000000005837c000 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 rest_init+0x16b/0x2b0 init/main.c:757 start_kernel+0x3ef/0x4d0 init/main.c:1206 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x148