rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-....: (1 GPs behind) idle=04d4/1/0x4000000000000000 softirq=21729/21731 fqs=2100
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6976
(detected by 0, t=10505 jiffies, g=27645, q=1494 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6976 Comm: syz.0.810 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5401 [inline]
RIP: 0010:lock_is_held_type+0x95/0x190 kernel/locking/lockdep.c:5705
Code: c7 00 1f 8c 8a e8 eb 12 00 00 65 ff 05 64 71 d5 75 83 bb d8 0a 00 00 00 7e 4b 44 89 fd 49 89 df 49 81 c7 e0 0a 00 00 45 31 e4 <49> 83 fc 31 73 24 4c 89 ff 4c 89 f6 e8 2a 02 00 00 85 c0 75 2a 49
RSP: 0018:ffffc900001e0a98 EFLAGS: 00000097
RAX: 0000000000000006 RBX: ffff88802a0f3b80 RCX: 0000000000000000
RDX: ffff88802a0f3b80 RSI: ffffffff8cb2d620 RDI: ffff88802a0f4688
RBP: 00000000ffffffff R08: dffffc0000000000 R09: 1ffffffff215ec48
R10: dffffc0000000000 R11: fffffbfff215ec49 R12: 0000000000000002
R13: 0000000000000046 R14: ffffffff8cb2d620 R15: ffff88802a0f46b0
FS: 00007f61a17196c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff882a36dc8 CR3: 0000000057b8b000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
trace_call_bpf+0x19e/0x6b0 kernel/trace/bpf_trace.c:135
perf_trace_run_bpf_submit+0x79/0x1c0 kernel/events/core.c:9997
perf_trace_preemptirq_template+0x268/0x320 include/trace/events/preemptirq.h:14
trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40
trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44
asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:variable_ffs arch/x86/include/asm/bitops.h:319 [inline]
RIP: 0010:handle_softirqs+0x1c8/0x930 kernel/softirq.c:584
Code: 89 7c 24 44 0f b7 db 48 c7 c7 00 08 8b 8a e8 df b1 dd 08 65 66 c7 05 15 37 b4 7e 00 00 e8 40 72 39 00 fb 49 c7 c6 c0 a0 80 8c <89> 5c 24 4c b8 ff ff ff ff 0f bc 44 24 4c 41 89 c5 41 ff c5 0f 84
RSP: 0018:ffffc900001e0e00 EFLAGS: 00000286
RAX: 00bd12719a6d1000 RBX: 0000000000000200 RCX: 00bd12719a6d1000
RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0f60
RBP: ffffc900001e0f30 R08: ffffffff90af62ef R09: 1ffffffff215ec5d
R10: dffffc0000000000 R11: fffffbfff215ec5e R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff8c80a0c0 R15: 000000000000000a
__do_softirq kernel/softirq.c:630 [inline]
invoke_softirq kernel/softirq.c:470 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:rcu_read_unlock_special+0x0/0x510 kernel/rcu/tree_plugin.h:630
Code: d6 22 66 00 eb b0 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 94 49 89 fd 4c 89 f7 e8 bc 22 66 00 4c 89 ef eb 84 0f 1f 80 00 00 00 00 <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec c0 00
RSP: 0018:ffffc9001bbf75e8 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffff88802a0f3fbc RCX: 0000000000080000
RDX: ffffc9000e019000 RSI: 00000000000531b7 RDI: ffff88802a0f3b80
RBP: dffffc0000000000 R08: ffff88801c0dfbbf R09: 1ffff1100381bf77
R10: dffffc0000000000 R11: ffffed100381bf78 R12: 1ffff1100541e7f7
R13: 0000000000000003 R14: ffff88802a0f3fc0 R15: dffffc0000000000
__rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
rcu_read_unlock include/linux/rcupdate.h:823 [inline]
page_ext_put+0x91/0xb0 mm/page_ext.c:182
page_table_check_free include/linux/page_table_check.h:46 [inline]
free_pages_prepare mm/page_alloc.c:1487 [inline]
free_pcp_prepare mm/page_alloc.c:1536 [inline]
free_unref_page_prepare+0x8c4/0x9a0 mm/page_alloc.c:3413
free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
slab_alloc_node mm/slub.c:3359 [inline]
slab_alloc mm/slub.c:3367 [inline]
__kmem_cache_alloc_lru mm/slub.c:3374 [inline]
kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383
vm_area_dup+0x23/0x1a0 kernel/fork.c:467
dup_mmap kernel/fork.c:646 [inline]
dup_mm kernel/fork.c:1546 [inline]
copy_mm+0xb28/0x1690 kernel/fork.c:1595
copy_process+0x1979/0x4030 kernel/fork.c:2356
kernel_clone+0x24b/0x900 kernel/fork.c:2762
__do_sys_clone kernel/fork.c:2903 [inline]
__se_sys_clone kernel/fork.c:2887 [inline]
__x64_sys_clone+0x1a7/0x220 kernel/fork.c:2887
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: 0033:0x7f61a079c799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f61a1718fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f61a0a16090 RCX: 00007f61a079c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000009040000
RBP: 00007f61a0832bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f61a0a16128 R14: 00007f61a0a16090 R15: 00007ffdd8807ee8
task:syz.0.810 state:R running task stack:24304 pid:6976 ppid:4266 flags:0x00004008
Call Trace: