rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10969/1:b..l
(detected by 0, t=10506 jiffies, g=52069, q=696 ncpus=2)
task:syz.0.2364 state:R running task stack:25712 pid:10969 ppid:4271 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6875
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:should_resched arch/x86/include/asm/preempt.h:103 [inline]
RIP: 0010:__local_bh_enable_ip+0x13e/0x1c0 kernel/softirq.c:428
Code: 8a e8 06 d2 e1 08 65 66 8b 05 be 66 b4 7e 66 85 c0 75 54 bf 01 00 00 00 e8 6f 82 09 00 e8 fa 5d 39 00 fb 65 8b 05 6a 33 b3 7e <85> c0 75 05 e8 79 47 b1 ff 48 c7 04 24 0e 36 e0 45 4b c7 04 37 00
RSP: 0018:ffffc900049177e0 EFLAGS: 00000282
RAX: 0000000000000000 RBX: 0000000000000200 RCX: 9f5cce057d0e3400
RDX: dffffc0000000000 RSI: ffffffff8a8c1820 RDI: ffffffff8adf6120
RBP: ffffc90004917870 R08: ffff8880b8f3580b R09: 1ffff110171e6b01
R10: dffffc0000000000 R11: ffffed10171e6b02 R12: ffffffff886f8885
R13: ffff888073e58c80 R14: dffffc0000000000 R15: 1ffff92000922efc
local_bh_enable include/linux/bottom_half.h:33 [inline]
xdp_test_run_batch net/bpf/test_run.c:340 [inline]
bpf_test_run_xdp_live+0x1835/0x1a90 net/bpf/test_run.c:362
bpf_prog_test_run_xdp+0x757/0xf80 net/bpf/test_run.c:1457
bpf_prog_test_run+0x31c/0x390 kernel/bpf/syscall.c:3695
__sys_bpf+0x62b/0x780 kernel/bpf/syscall.c:5050
__do_sys_bpf kernel/bpf/syscall.c:5136 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5134 [inline]
__x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5134
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6614b9e0d9
RSP: 002b:00007f6615b39028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f6614e25fa0 RCX: 00007f6614b9e0d9
RDX: 0000000000000048 RSI: 0000200000000600 RDI: 000000000000000a
RBP: 00007f6614c35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6614e26038 R14: 00007f6614e25fa0 R15: 00007ffcc9192e88
rcu: rcu_preempt kthread starved for 10290 jiffies! g52069 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:27312 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
schedule+0xb9/0x180 kernel/sched/core.c:6639
schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x303/0x1350 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 9 Comm: kworker/u4:0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: writeback wb_workfn (flush-8:0)
RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:kvm_wait+0x159/0x1b0 arch/x86/kernel/kvm.c:1064
Code: 89 df 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 4b 0f b6 1f e8 27 16 50 00 44 38 e3 75 10 66 90 0f 00 2d e9 f3 50 09 fb f4 16 ff ff ff fb e9 10 ff ff ff e8 27 74 f8 08 89 f9 80 e1 07 38
RSP: 0018:ffffc900000e6460 EFLAGS: 00000246
RAX: 59e73a6c76ea6000 RBX: 0000000000000003 RCX: 59e73a6c76ea6000
RDX: dffffc0000000000 RSI: ffffffff8a8c1820 RDI: ffffffff8adf6120
RBP: ffffc900000e6510 R08: ffffffff90b12247 R09: 1ffffffff2162448
R10: dffffc0000000000 R11: fffffbfff2162449 R12: 0000000000000003
R13: dffffc0000000000 R14: dffffc0000000000 R15: 1ffff9200001cc8c
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f60919eb7c0 CR3: 000000005beb4000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
pv_wait arch/x86/include/asm/paravirt.h:603 [inline]
pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
__pv_queued_spin_lock_slowpath+0x60f/0x9c0 kernel/locking/qspinlock.c:511
pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline]
queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51
queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
do_raw_spin_lock+0x265/0x2f0 kernel/locking/spinlock_debug.c:115
page_vma_mapped_walk+0x12d6/0x1940 mm/page_vma_mapped.c:-1
page_vma_mkclean_one+0x356/0x690 mm/rmap.c:958
page_mkclean_one+0x1ec/0x3b0 mm/rmap.c:1018
rmap_walk_file+0x36d/0x740 mm/rmap.c:2508
rmap_walk mm/rmap.c:2526 [inline]
folio_mkclean+0x1e1/0x360 mm/rmap.c:1050
folio_clear_dirty_for_io+0x208/0xcb0 mm/page-writeback.c:2886
mpage_submit_page+0x8a/0x210 fs/ext4/inode.c:2124
mpage_process_page_bufs+0x6c6/0x8a0 fs/ext4/inode.c:2258
mpage_prepare_extent_to_map+0xba4/0x1690 fs/ext4/inode.c:2683
ext4_writepages+0x9da/0x2e70 fs/ext4/inode.c:2811
do_writepages+0x3c6/0x640 mm/page-writeback.c:2491
__writeback_single_inode+0x153/0x1170 fs/fs-writeback.c:1673
writeback_sb_inodes+0xad5/0x17f0 fs/fs-writeback.c:1964
__writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2035
wb_writeback+0x484/0xd40 fs/fs-writeback.c:2140
wb_check_old_data_flush fs/fs-writeback.c:2240 [inline]
wb_do_writeback fs/fs-writeback.c:2293 [inline]
wb_workfn+0xb68/0xee0 fs/fs-writeback.c:2321
process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295