rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=1f54/1/0x4000000000000000 softirq=76891/76892 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P15018/3:b..l
rcu: (detected by 0, t=10505 jiffies, g=71361, q=80 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 15022 Comm: modprobe 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:advance_sched+0x503/0xc90 net/sched/sch_taprio.c:966
Code: e3 31 50 f8 66 85 ed 0f 8e 31 02 00 00 48 8b 04 24 48 05 30 01 00 00 4d 8d 6e 80 48 ff cd 45 31 ff 48 89 44 24 50 48 c1 e8 03 <48> 89 44 24 70 48 89 6c 24 30 bf 10 00 00 00 4c 89 fe e8 e6 32 50
RSP: 0018:ffffc90000a08c70 EFLAGS: 00000012
RAX: 1ffff1100af70326 RBX: ffff888057b81928 RCX: 0000000000010000
RDX: ffff88801e770000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200014117c R12: dffffc0000000000
R13: ffff888057b814c0 R14: ffff888057b81540 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125f3a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc926874000 CR3: 000000006b261000 CR4: 0000000000350ef0
Call Trace:
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x51c/0xc30 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x17df/0x2390 arch/x86/kernel/unwind_orc.c:664
Code: 24 48 01 c6 4c 89 f7 48 89 da e8 4c 0e 00 00 84 c0 0f 84 47 01 00 00 48 bd 00 00 00 00 00 fc ff df 48 8b 44 24 20 0f b6 04 28 <84> c0 0f 85 f4 08 00 00 b3 01 8b 84 24 84 00 00 00 41 39 06 4c 8b
RSP: 0018:ffffc90002ec70b8 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffffff90215d5a RCX: 0000000000000001
RDX: ffffc90002ec71c8 RSI: dffffc0000000000 RDI: ffffc90002ec7688
RBP: dffffc0000000000 R08: ffffc90002ec7688 R09: ffffc90002ec71d8
R10: dffffc0000000000 R11: fffff520005d8e3d R12: ffffc90002ec7688
R13: ffffc90002ec71d8 R14: ffffc90002ec7188 R15: 1ffffffff2042bab
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:397 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414
kasan_kmalloc include/linux/kasan.h:262 [inline]
__kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5771
kmalloc_noprof include/linux/slab.h:957 [inline]
slab_free_hook mm/slub.c:2492 [inline]
slab_free mm/slub.c:6663 [inline]
kmem_cache_free+0x16b/0x620 mm/slub.c:6774
remove_vma mm/vma.c:462 [inline]
vms_complete_munmap_vmas+0x626/0x8a0 mm/vma.c:1296
__mmap_complete+0x7b/0x610 mm/vma.c:2540
__mmap_region mm/vma.c:2717 [inline]
mmap_region+0x11e3/0x1d10 mm/vma.c:2786
do_mmap+0xc45/0x10d0 mm/mmap.c:558
vm_mmap_pgoff+0x2a6/0x4d0 mm/util.c:581
ksys_mmap_pgoff+0x51f/0x760 mm/mmap.c:604
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc92689f242
Code: 08 00 04 00 00 eb e2 90 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 33 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5e 5b 5d c3 0f 1f 00 c7 05 46 40 01 00 16 00
RSP: 002b:00007fffde4d36e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fc9265c3000 RCX: 00007fc92689f242
RDX: 0000000000000005 RSI: 0000000000008000 RDI: 00007fc9265c3000
RBP: 0000000000000812 R08: 0000000000000000 R09: 0000000000003000
R10: 0000000000000812 R11: 0000000000000206 R12: 00007fffde4d3738
R13: 00007fc926873b20 R14: 00007fffde4d3b20 R15: 00000ffffbc9a6e0
task:syz.5.2297 state:R running task stack:23536 pid:15018 tgid:15013 ppid:5821 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_notrace+0xd1/0x110 kernel/sched/core.c:7140
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:752
trace_lock_acquire include/trace/events/lock.h:24 [inline]
lock_acquire+0x5f/0x340 kernel/locking/lockdep.c:5831
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+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
unpoison_slab_object mm/kasan/common.c:339 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4948 [inline]
slab_alloc_node mm/slub.c:5258 [inline]
kmem_cache_alloc_node_noprof+0x43c/0x720 mm/slub.c:5310
__alloc_skb+0x255/0x430 net/core/skbuff.c:679
alloc_skb include/linux/skbuff.h:1383 [inline]
pfkey_send_acquire+0x606/0x2cb0 net/key/af_key.c:3186
km_query+0x11c/0x210 net/xfrm/xfrm_state.c:2780
xfrm_state_find+0x3bca/0x5400 net/xfrm/xfrm_state.c:1559
xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2522 [inline]
xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:2573 [inline]
xfrm_resolve_and_create_bundle+0x768/0x2f60 net/xfrm/xfrm_policy.c:2871
xfrm_lookup_with_ifid+0x2a7/0x1a70 net/xfrm/xfrm_policy.c:3205
xfrm_lookup net/xfrm/xfrm_policy.c:3336 [inline]
xfrm_lookup_route+0x3c/0x1c0 net/xfrm/xfrm_policy.c:3347
udp_sendmsg+0x142e/0x2170 net/ipv4/udp.c:1450
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0x19c/0x270 net/socket.c:742
____sys_sendmsg+0x52d/0x820 net/socket.c:2592
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2646
__sys_sendmmsg+0x227/0x430 net/socket.c:2735
__do_sys_sendmmsg net/socket.c:2762 [inline]
__se_sys_sendmmsg net/socket.c:2759 [inline]
__x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2759
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa8add8f749
RSP: 002b:00007fa8aebe9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fa8adfe6090 RCX: 00007fa8add8f749
RDX: 000000000800001d RSI: 0000200000007fc0 RDI: 0000000000000003
RBP: 00007fa8ade13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000001c R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa8adfe6128 R14: 00007fa8adfe6090 R15: 00007ffd5d92ea48
rcu: rcu_preempt kthread starved for 10505 jiffies! g71361 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:27184 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 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: 14987 Comm: syz.2.2290 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:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xcd4/0x12b0 kernel/smp.c:877
Code: 89 ee 83 e6 01 31 ff e8 1a 9a 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 c5 95 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 a9 95 0b 00 eb e4 44
RSP: 0018:ffffc9000515f0c0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff110170e8129 RCX: ffff888093b50000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000515f240 R08: ffff888032626147 R09: 1ffff110064c4c28
R10: dffffc0000000000 R11: ffffffff817637d0 R12: ffff8880b8740948
R13: dffffc0000000000 R14: ffff8880b863bb00 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125e3a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30c1bff8 CR3: 00000000446d4000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline]
flush_tlb_mm_range+0x6b1/0x1280 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:490 [inline]
zap_pte_range mm/memory.c:1881 [inline]
zap_pmd_range mm/memory.c:1946 [inline]
zap_pud_range mm/memory.c:1975 [inline]
zap_p4d_range mm/memory.c:1996 [inline]
unmap_page_range+0x3739/0x4170 mm/memory.c:2017
unmap_single_vma mm/memory.c:2059 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:2101
exit_mmap+0x239/0xb10 mm/mmap.c:1277
__mmput+0x118/0x430 kernel/fork.c:1173
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x658/0x2310 kernel/exit.c:959
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8bda18f749
Code: Unable to access opcode bytes at 0x7f8bda18f71f.
RSP: 002b:00007f8bd83cd038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: 0000000000010106 RBX: 00007f8bda3e6090 RCX: 00007f8bda18f749
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f8bda213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8bda3e6128 R14: 00007f8bda3e6090 R15: 00007ffc1cfb7408