rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P15928/1:b..l P15927
rcu: (detected by 0, t=10502 jiffies, g=68909, q=2132 ncpus=2)
task:syz.9.2480 state:R running task stack:26296 pid:15927 tgid:15917 ppid:15222 task_flags:0x400140 flags:0x00080000
Call Trace:
sched_show_task kernel/sched/core.c:7819 [inline]
sched_show_task+0x423/0x630 kernel/sched/core.c:7794
rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:292 [inline]
print_other_cpu_stall kernel/rcu/tree_stall.h:681 [inline]
check_cpu_stall kernel/rcu/tree_stall.h:856 [inline]
rcu_pending kernel/rcu/tree.c:3667 [inline]
rcu_sched_clock_irq+0x2634/0x31f0 kernel/rcu/tree.c:2704
update_process_times+0x178/0x2d0 kernel/time/timer.c:2474
tick_sched_handle kernel/time/tick-sched.c:298 [inline]
tick_nohz_handler+0x506/0x720 kernel/time/tick-sched.c:319
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x64e/0xc40 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x3c0 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872
Code: a6 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 82 b5 ee 0e 0f 82 74 02 00 00 8b 35 1a e6 ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 99 a6 18 12 0f 85 ad 02 00 00 48 83 c4
RSP: 0018:ffffc90005b57950 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c9620 RCX: 00000000bf3fbf97
RDX: 0000000000000000 RSI: ffffffff8daa7ab3 RDI: ffffffff8bf2b300
RBP: 0000000000000002 R08: 00000000ac0d5af0 R09: 000000000ac0d5af
R10: 0000000000000002 R11: ffff8880315daff0 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]
____bpf_get_current_ancestor_cgroup_id kernel/bpf/helpers.c:431 [inline]
bpf_get_current_ancestor_cgroup_id+0x3a/0x480 kernel/bpf/helpers.c:425
bpf_prog_2a80ded90d5f4b4b+0x41/0x4c
bpf_dispatcher_nop_func include/linux/bpf.h:1376 [inline]
__bpf_prog_run include/linux/filter.h:723 [inline]
bpf_prog_run include/linux/filter.h:730 [inline]
bpf_prog_run_pin_on_cpu include/linux/filter.h:747 [inline]
bpf_flow_dissect+0x21b/0x740 net/core/flow_dissector.c:1024
bpf_prog_test_run_flow_dissector+0x438/0x980 net/bpf/test_run.c:1482
bpf_prog_test_run kernel/bpf/syscall.c:4703 [inline]
__sys_bpf+0x1035/0x4980 kernel/bpf/syscall.c:6182
__do_sys_bpf kernel/bpf/syscall.c:6274 [inline]
__se_sys_bpf kernel/bpf/syscall.c:6272 [inline]
__x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:6272
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: 0033:0x7f645098f749
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:00007f6451881038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f6450be6180 RCX: 00007f645098f749
RDX: 0000000000000050 RSI: 0000200000000740 RDI: 000000000000000a
RBP: 00007f6450a13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6450be6218 R14: 00007f6450be6180 R15: 00007fffd6d56d68
task:syz.9.2480 state:R running task stack:24200 pid:15928 tgid:15928 ppid:15222 task_flags:0x400640 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_notrace+0x62/0xe0 kernel/sched/core.c:7140
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x8e/0xc0 kernel/rcu/tree.c:752
trace_lock_acquire include/trace/events/lock.h:24 [inline]
lock_acquire+0x2cd/0x330 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+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
save_stack+0x160/0x1f0 mm/page_owner.c:165
__set_page_owner+0x91/0x560 mm/page_owner.c:341
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846
prep_new_page mm/page_alloc.c:1854 [inline]
get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915
__alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
folio_alloc_mpol_noprof+0x36/0x2f0 mm/mempolicy.c:2505
shmem_alloc_folio+0x135/0x160 mm/shmem.c:1890
shmem_alloc_and_add_folio+0x494/0xc20 mm/shmem.c:1932
shmem_get_folio_gfp+0x67f/0x1610 mm/shmem.c:2556
shmem_get_folio mm/shmem.c:2662 [inline]
shmem_write_begin+0x1a4/0x3b0 mm/shmem.c:3315
generic_perform_write+0x3c4/0x900 mm/filemap.c:4314
shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3490
__kernel_write_iter+0x31a/0xb10 fs/read_write.c:619
dump_emit_page fs/coredump.c:1298 [inline]
dump_user_range+0x413/0xb70 fs/coredump.c:1372
elf_core_dump+0x29c3/0x3c10 fs/binfmt_elf.c:2111
coredump_write fs/coredump.c:1049 [inline]
do_coredump fs/coredump.c:1126 [inline]
vfs_coredump+0x2b85/0x55e0 fs/coredump.c:1200
get_signal+0x22e1/0x26d0 kernel/signal.c:3019
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x38a/0x8c0 kernel/entry/common.c:196
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f645098f751
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f6450be6090 RCX: 00007f645098f749
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007f6450a13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f6450be6128 R14: 00007f6450be6090 R15: 00007fffd6d56d68
rcu: rcu_preempt kthread starved for 10336 jiffies! g68909 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:27512 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 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: c6 5f 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 12 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:ffffc90000197de8 EFLAGS: 000002c6
RAX: 00000000036e8c91 RBX: 0000000000000001 RCX: ffffffff8b7806d9
RDX: 0000000000000000 RSI: ffffffff8dacdb2d RDI: ffffffff8bf2b300
RBP: ffffed1003b56498 R08: 0000000000000001 R09: ffffed10170a673d
R10: ffff8880b85339eb R11: ffff88801dab2ff0 R12: 0000000000000001
R13: ffff88801dab24c0 R14: ffffffff9088aed0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881249f6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbd03f5be21 CR3: 00000000286c1000 CR4: 00000000003526f0
DR0: 0000000000800003 DR1: 00000000000001f5 DR2: 0000000000000483
DR3: 0000000000000007 DR6: 00000000ffff0ff0 DR7: 0000000000000400
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
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x148