rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6330/1:b..l rcu: (detected by 1, t=10502 jiffies, g=17001, q=1980 ncpus=2) task:syz-executor state:R running task stack:18872 pid:6330 tgid:6330 ppid:6329 task_flags:0x400140 flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1539/0x5080 kernel/sched/core.c:6907 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234 irqentry_exit+0x599/0x620 kernel/entry/common.c:239 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:save_netdev_trace_buffer+0x130/0x610 net/core/dev.c:13454 Code: e8 55 1e 3a f8 48 89 df 89 c6 e8 7b f6 ff ff 41 89 c7 48 8b 44 24 28 4c 8d b0 18 03 00 00 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 <74> 08 4c 89 f7 e8 36 3e b8 f8 49 63 c7 49 8b 1e 4c 39 f3 4c 89 74 RSP: 0018:ffffc90003d7f520 EFLAGS: 00000246 RAX: 1ffff1100ab22863 RBX: ffffc90003d7f5a0 RCX: ffff88802c36dac0 RDX: 0000000000000000 RSI: ffffffff8968e6af RDI: ffffffff8968e6af RBP: ffffc90003d7f6c8 R08: ffffffff81d453b6 R09: ffffffff8e760160 R10: ffffc90003d7f438 R11: ffffffff81b02c90 R12: 00000000ffffffff R13: dffffc0000000000 R14: ffff888055914318 R15: 0000000000000008 __dev_put include/linux/netdevice.h:4389 [inline] netdev_put include/linux/netdevice.h:4456 [inline] dev_put include/linux/netdevice.h:4481 [inline] __netlink_deliver_tap_skb net/netlink/af_netlink.c:312 [inline] __netlink_deliver_tap+0x636/0x8b0 net/netlink/af_netlink.c:325 netlink_deliver_tap+0x19c/0x1b0 net/netlink/af_netlink.c:338 __netlink_sendskb net/netlink/af_netlink.c:1260 [inline] netlink_sendskb+0x68/0x140 net/netlink/af_netlink.c:1269 netlink_unicast+0x3a3/0x9b0 net/netlink/af_netlink.c:1359 netlink_rcv_skb+0x2b6/0x4b0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec+0x18f/0x1d0 net/socket.c:737 __sock_sendmsg net/socket.c:752 [inline] __sys_sendto+0x3ff/0x590 net/socket.c:2221 __do_sys_sendto net/socket.c:2228 [inline] __se_sys_sendto net/socket.c:2224 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2224 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f65c4f5994e RSP: 002b:00007ffead44cb78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055557554f500 RCX: 00007f65c4f5994e RDX: 0000000000000028 RSI: 00007f65c5cf4670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffead44cbf4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f65c5cf4670 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 4337 jiffies! g17001 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:27624 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1539/0x5080 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 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:467 ret_from_fork+0x51b/0xa40 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: 6265 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xce5/0x1270 kernel/smp.c:877 Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 64 db 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 0f d7 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 f3 d6 RSP: 0018:ffffc90002e47680 EFLAGS: 00000293 RAX: ffffffff81b912ed RBX: 1ffff110170884d5 RCX: ffff88807e0d9e40 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90002e477c0 R08: ffffffff9010f6b7 R09: 1ffffffff2021ed6 R10: dffffc0000000000 R11: fffffbfff2021ed7 R12: ffff8880b84426a8 R13: dffffc0000000000 R14: ffff8880b853bd80 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125396000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f51f775a38 CR3: 000000000e54c000 CR4: 00000000003526f0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043 __flush_tlb_multi arch/x86/include/asm/paravirt.h:57 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline] flush_tlb_mm_range+0x5c3/0x10c0 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:505 [inline] tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:403 tlb_finish_mmu+0xf9/0x230 mm/mmu_gather.c:529 free_ldt_pgtables+0x19d/0x350 arch/x86/kernel/ldt.c:411 arch_exit_mmap arch/x86/include/asm/mmu_context.h:232 [inline] exit_mmap+0x1b7/0x9c0 mm/mmap.c:1287 __mmput+0x118/0x430 kernel/fork.c:1174 exit_mm+0x168/0x220 kernel/exit.c:581 do_exit+0x62e/0x2310 kernel/exit.c:959 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112 __do_sys_exit_group kernel/exit.c:1123 [inline] __se_sys_exit_group kernel/exit.c:1121 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1121 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff2756f16c5 Code: Unable to access opcode bytes at 0x7ff2756f169b. RSP: 002b:00007ffdceb6eba8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 000055f51f780fa0 RCX: 00007ff2756f16c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 000055f51f76c910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdceb6ebf0 R14: 0000000000000000 R15: 0000000000000000