rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=0044/1/0x4000000000000000 softirq=137542/137543 fqs=5
rcu: 	(detected by 1, t=10502 jiffies, g=180497, q=381 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 22862 Comm: syz.8.4848 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:_find_first_zero_bit+0xa/0xb0 lib/find_bit.c:148
Code: dc e9 77 fd e9 7c ff ff ff 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 41 55 <41> 54 53 48 85 f6 74 46 48 89 f3 49 89 fe 49 bc 00 00 00 00 00 fc
RSP: 0018:ffffc9000426fbf0 EFLAGS: 00000002
RAX: 0000000000000040 RBX: ffff888065393150 RCX: dffffc0000000000
RDX: ffffc9001b410000 RSI: 0000000000000002 RDI: ffff888065393250
RBP: ffff88802d2752f0 R08: 1ffff1100ca724e9 R09: 0000000000000000
R10: ffff88806539288c R11: fffff5200084df78 R12: dffffc0000000000
R13: 1ffffffff1c63bd7 R14: 0000000080000000 R15: 0000000000000002
FS:  00007fddc101e6c0(0000) GS:ffff888124ff3000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000002100 CR3: 0000000076e04000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 find_first_zero_bit include/linux/find.h:391 [inline]
 __mm_get_cid kernel/sched/sched.h:3831 [inline]
 mm_get_cid+0xe2/0x160 kernel/sched/sched.h:3846
 sched_mm_cid_fork+0x3f6/0xdd0 kernel/sched/core.c:10733
 bprm_execve+0xdc3/0x1450 fs/exec.c:1782
 do_execveat_common+0x595/0x710 fs/exec.c:1911
 __do_sys_execveat fs/exec.c:2006 [inline]
 __se_sys_execveat fs/exec.c:1999 [inline]
 __x64_sys_execveat+0xc7/0xf0 fs/exec.c:1999
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fddc019c799
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:00007fddc101e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000142
RAX: ffffffffffffffda RBX: 00007fddc0415fa0 RCX: 00007fddc019c799
RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000005
RBP: 00007fddc0232c99 R08: 0000000000001000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fddc0416038 R14: 00007fddc0415fa0 R15: 00007fffacd36f38
 </TASK>
rcu: rcu_preempt kthread starved for 10492 jiffies! g180497 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:
 <TASK>
 context_switch kernel/sched/core.c:5352 [inline]
 __schedule+0x165c/0x5560 kernel/sched/core.c:6964
 __schedule_loop kernel/sched/core.c:7047 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7062
 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 17550 Comm: syz-executor Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:variable_ffs arch/x86/include/asm/bitops.h:312 [inline]
RIP: 0010:handle_softirqs+0x160/0x840 kernel/softirq.c:614
Code: 89 6c 24 20 0f b7 db 48 c7 c7 e0 2e cb 8b e8 17 e9 32 0a 65 66 c7 05 d5 c9 b9 11 00 00 e8 68 a9 45 00 fb 48 c7 c5 c0 a0 60 8e <b8> ff ff ff ff 0f bc c3 41 89 c6 41 ff c6 0f 84 09 04 00 00 89 5c
RSP: 0000:ffffc90000a08f28 EFLAGS: 00000202
RAX: 0000000000aa3ef4 RBX: 0000000000000100 RCX: 0000000000000103
RDX: 0000000000000002 RSI: ffffffff8e05f4c1 RDI: ffffffff8c2a8e80
RBP: ffffffff8e60a0c0 R08: ffffffff903444f7 R09: 1ffffffff206889e
R10: dffffc0000000000 R11: fffffbfff206889f R12: 0000000000000000
R13: 0000000000000000 R14: ffff88802cfddb80 R15: dffffc0000000000
FS:  0000555563eea500(0000) GS:ffff8881250f3000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555563f05a28 CR3: 0000000057ff6000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __do_softirq kernel/softirq.c:660 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x220 kernel/softirq.c:739
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:756
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xce5/0x1290 kernel/smp.c:891
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 54 fc 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 ff f7 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 e3 f7
RSP: 0000:ffffc90006797840 EFLAGS: 00000293
RAX: ffffffff81baa99d RBX: 1ffff11017088575 RCX: ffff88802cfddb80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90006797970 R08: ffffffff903444f7 R09: 1ffffffff206889e
R10: dffffc0000000000 R11: fffffbfff206889f R12: ffff8880b8442ba8
R13: dffffc0000000000 R14: ffff8880b853c080 R15: 0000000000000000
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:57 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
 flush_tlb_mm_range+0x5d7/0x10d0 arch/x86/mm/tlb.c:1451
 flush_tlb_page arch/x86/include/asm/tlbflush.h:345 [inline]
 ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:103
 wp_page_copy mm/memory.c:3925 [inline]
 do_wp_page+0x3d6b/0x4c20 mm/memory.c:4320
 handle_pte_fault mm/memory.c:6471 [inline]
 __handle_mm_fault mm/memory.c:6593 [inline]
 handle_mm_fault+0x151d/0x3170 mm/memory.c:6762
 do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fddc0161320
Code: bb 28 00 48 8d 0c 1e 49 39 d0 49 89 48 60 0f 95 c2 48 29 d8 0f b6 d2 48 83 c8 01 48 c1 e2 02 48 09 da 48 83 ca 01 48 89 56 08 <48> 89 41 08 48 8d 4e 10 eb b0 48 8d 0d bf df 0c 00 ba 9e 10 00 00
RSP: 002b:00007fffacd37140 EFLAGS: 00010206
RAX: 00000000000185e1 RBX: 0000000000008040 RCX: 0000555563f05a20
RDX: 0000000000008041 RSI: 0000555563efd9e0 RDI: 0000000000000004
RBP: 0000000000000802 R08: 00007fddc03ece20 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000008030
R13: 0000000000000000 R14: 00007fddc03ece80 R15: 0000000000000000
 </TASK>