rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6876/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=19221, q=449 ncpus=2)
task:modprobe        state:R  running task     stack:24232 pid:6876  ppid:12     flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5380 [inline]
 __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
 preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7009
 irqentry_exit+0x67/0x70 kernel/entry/common.c:438
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:debug_lockdep_rcu_enabled+0x29/0x30 kernel/rcu/update.c:320
Code: cc f3 0f 1e fa 31 c0 83 3d 3f 71 db 03 00 74 1d 83 3d c6 a4 db 03 00 74 14 65 48 8b 0d d0 91 94 75 31 c0 83 b9 dc 0a 00 00 00 <0f> 94 c0 c3 cc cc cc 66 0f 1f 00 48 8b 3c 24 e8 43 fb ff ff 66 90
RSP: 0018:ffffc9000484f338 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000004 RCX: ffff88802c658000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000003
RBP: ffffc9000484f510 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff2e582b4 R12: ffff88807ab8b00c
R13: 0000000000000000 R14: 0000000000000001 R15: ffff88807ab8be70
 mt_slot lib/maple_tree.c:814 [inline]
 mas_slot lib/maple_tree.c:847 [inline]
 mas_validate_parent_slot lib/maple_tree.c:7041 [inline]
 mt_validate+0x705/0x4530 lib/maple_tree.c:7230
 validate_mm+0xb1/0x420 mm/mmap.c:288
 __split_vma+0xa2e/0xc00 mm/mmap.c:2425
 do_vmi_align_munmap+0x2dc/0x1660 mm/mmap.c:2501
 do_vmi_munmap+0x252/0x2d0 mm/mmap.c:2660
 __mmap_region mm/mmap.c:2710 [inline]
 mmap_region+0x741/0x2020 mm/mmap.c:2941
 do_mmap+0x92f/0x10a0 mm/mmap.c:1385
 vm_mmap_pgoff+0x1c0/0x400 mm/util.c:556
 ksys_mmap_pgoff+0x520/0x700 mm/mmap.c:1431
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb1eea2f242
RSP: 002b:00007fff0c2b9c08 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fb1ee743000 RCX: 00007fb1eea2f242
RDX: 0000000000000005 RSI: 0000000000008000 RDI: 00007fb1ee743000
RBP: 0000000000000812 R08: 0000000000000000 R09: 0000000000003000
R10: 0000000000000812 R11: 0000000000000206 R12: 00007fff0c2b9c58
R13: 00007fb1eea0c580 R14: 00007fff0c2ba080 R15: 00000fffe1857384
 </TASK>
rcu: rcu_preempt kthread starved for 10536 jiffies! g19221 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:27752 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5380 [inline]
 __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
 schedule+0xbd/0x170 kernel/sched/core.c:6773
 schedule_timeout+0x160/0x280 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:148
Code: cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d a3 14 39 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 66 0f 1f 00 55 41 57 41 56
RSP: 0018:ffffc90000187de0 EFLAGS: 000002c6
RAX: 23b3cd6065625a00 RBX: ffffffff8161881b RCX: 23b3cd6065625a00
RDX: 0000000000000001 RSI: ffffffff8aaabce0 RDI: ffffffff8afc6f80
RBP: ffffc90000187f20 R08: ffff8880b8f36b2b R09: 1ffff110171e6d65
R10: dffffc0000000000 R11: ffffed10171e6d66 R12: ffffffff8e4a93e8
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110037cb780
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f188881c26c CR3: 000000002d24b000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:753
 default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97
 cpuidle_idle_call kernel/sched/idle.c:170 [inline]
 do_idle+0x1eb/0x510 kernel/sched/idle.c:282
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380
 start_secondary+0xee/0xf0 arch/x86/kernel/smpboot.c:323
 secondary_startup_64_no_verify+0x179/0x17b
 </TASK>