rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=1974/1/0x4000000000000000 softirq=124377/124378 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P28497 rcu: (detected by 1, t=10502 jiffies, g=139937, q=196 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 28497 Comm: syz.5.7528 Not tainted 6.14.0-rc1-syzkaller-00207-g595ab66f1bec #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1799 [inline] RIP: 0010:__hrtimer_run_queues+0x566/0xd30 kernel/time/hrtimer.c:1865 Code: a0 12 00 85 db 74 15 e8 18 9d 12 00 4c 89 f7 4d 89 eb e8 2d 11 4c 0a 41 89 c5 eb 61 e8 03 9d 12 00 65 4c 8b 3c 25 80 d6 03 00 <49> 81 c7 d8 0a 00 00 4c 89 fb 48 c1 eb 03 49 bc 00 00 00 00 00 fc RSP: 0018:ffffc90000007d40 EFLAGS: 00000006 RAX: ffffffff81acc29d RBX: 0000000000000000 RCX: ffff88803d7e3c00 RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000007ea0 R08: ffffffff81acc27f R09: 1ffffffff2036a8e R10: dffffc0000000000 R11: fffffbfff2036a8f R12: 1ffff110170c58eb R13: ffffffff89f72310 R14: ffff888028353340 R15: ffff88803d7e3c00 FS: 00007f54159d06c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c41112c CR3: 0000000032e8c000 CR4: 0000000000350ef0 Call Trace: hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x112/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5251 Code: c9 50 e8 49 0a 0c 00 48 83 c4 08 4c 89 f7 e8 fd 39 00 00 e9 de 04 00 00 4c 89 f7 e8 80 ed 69 0a e8 3b 75 38 00 fb 48 8b 5d c0 <48> 8d bb 08 16 00 00 48 89 f8 48 c1 e8 03 49 be 00 00 00 00 00 fc RSP: 0018:ffffc90005e06a88 EFLAGS: 00000282 RAX: 922ac1e3718c8300 RBX: ffff88803d7e3c00 RCX: ffffffff819b323a RDX: dffffc0000000000 RSI: ffffffff8c0aa680 RDI: ffffffff8c608b40 RBP: ffffc90005e06ad0 R08: ffffffff942f990f R09: 1ffffffff285f321 R10: dffffc0000000000 R11: fffffbfff285f322 R12: 1ffff110170c7eee R13: dffffc0000000000 R14: ffff8880b863e940 R15: ffff8880b863f770 context_switch kernel/sched/core.c:5380 [inline] __schedule+0x1916/0x4c90 kernel/sched/core.c:6764 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7086 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:__sanitizer_cov_trace_pc+0x5d/0x70 kernel/kcov.c:235 Code: 08 16 00 00 83 fa 02 75 21 48 8b 91 10 16 00 00 48 8b 32 48 8d 7e 01 8b 89 0c 16 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 09 e1 50 ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 RSP: 0018:ffffc90005e06e50 EFLAGS: 00000283 RAX: ffffffff8a941469 RBX: ffff8880343a9e40 RCX: 0000000000080000 RDX: ffffc90012fb3000 RSI: 000000000000acee RDI: 000000000000acef RBP: 00000000ffffff82 R08: ffffc90005e06fb7 R09: 1ffff92000bc0df6 R10: dffffc0000000000 R11: fffff52000bc0df7 R12: ffffc90005e06fe0 R13: dffffc0000000000 R14: ffffc90005e06f80 R15: 0000000000000002 ipv6_get_saddr_eval+0x29/0xf50 net/ipv6/addrconf.c:1582 __ipv6_dev_get_saddr+0x1d3/0x4b0 net/ipv6/addrconf.c:1753 ipv6_dev_get_saddr+0x555/0xc10 net/ipv6/addrconf.c:1889 ip6_route_get_saddr include/net/ip6_route.h:147 [inline] ip6_dst_lookup_tail+0xf18/0x14f0 net/ipv6/ip6_output.c:1133 ip6_dst_lookup_flow+0xb9/0x180 net/ipv6/ip6_output.c:1259 sctp_v6_get_dst+0x792/0x1e20 net/sctp/ipv6.c:326 sctp_transport_route+0x12e/0x2e0 net/sctp/transport.c:455 sctp_packet_config+0x460/0xdb0 net/sctp/output.c:103 sctp_packet_singleton+0x14d/0x320 net/sctp/outqueue.c:777 sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline] sctp_outq_flush+0x6d5/0x3e20 net/sctp/outqueue.c:1212 sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline] sctp_do_sm+0x59cc/0x60c0 net/sctp/sm_sideeffect.c:1169 sctp_primitive_ASSOCIATE+0x95/0xc0 net/sctp/primitive.c:73 __sctp_connect+0x9cd/0xe30 net/sctp/socket.c:1234 sctp_connect net/sctp/socket.c:4819 [inline] sctp_inet_connect+0x149/0x1f0 net/sctp/socket.c:4834 __sys_connect_file net/socket.c:2045 [inline] __sys_connect+0x28a/0x2d0 net/socket.c:2064 __do_sys_connect net/socket.c:2070 [inline] __se_sys_connect net/socket.c:2067 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2067 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5414b8cde9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f54159d0038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f5414da6160 RCX: 00007f5414b8cde9 RDX: 000000000000001c RSI: 0000400000000000 RDI: 0000000000000009 RBP: 00007f5414c0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5414da6160 R15: 00007ffe0a493a78 task:syz.5.7528 state:R running task stack:24560 pid:28497 tgid:28488 ppid:27681 task_flags:0x400140 flags:0x00004008 Call Trace: rcu: rcu_preempt kthread starved for 10502 jiffies! g139937 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:25752 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6856 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226 kthread+0x7ab/0x920 kernel/kthread.c:464 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 35 Comm: kworker/u8:2 Not tainted 6.14.0-rc1-syzkaller-00207-g595ab66f1bec #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x1bae/0x2d30 kernel/smp.c:885 Code: 89 e6 83 e6 01 31 ff e8 b0 e8 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 60 e4 0b 00 eb 41 f3 90 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 03 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 3b e4 0b RSP: 0018:ffffc90000ab7640 EFLAGS: 00000293 RAX: dffffc0000000000 RBX: 1ffff110170c8c99 RCX: ffff888143ec9e00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000ab7840 R08: ffffffff81b37b30 R09: 1ffffffff285f308 R10: dffffc0000000000 R11: fffffbfff285f309 R12: ffff8880b873fb48 R13: ffff8880b86464c8 R14: ffff8880b873fb40 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc9c71d8fe4 CR3: 000000000e738000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2118 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2328 text_poke_flush arch/x86/kernel/alternative.c:2519 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2526 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xbc/0x260 mm/kfence/core.c:850 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa68/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7ab/0x920 kernel/kthread.c:464 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244