rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5815/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=52217, q=421 ncpus=2)
task:syz-executor    state:R  running task     stack:19496 pid:5815  tgid:5815  ppid:5812   task_flags:0x400140 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5282 [inline]
 __schedule+0x14ed/0x5040 kernel/sched/core.c:6894
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7221
 irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x4a5/0x23d0 arch/x86/kernel/unwind_orc.c:520
Code: e0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 6d 18 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 80 18 00 00 41 0f b6 44 24 01 <83> e0 07 0f 84 6d 15 00 00 83 f8 01 4c 8b 7c 24 50 48 bd 00 00 00
RSP: 0018:ffffc90003c670f8 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffffff9029bd24 RCX: ffffffff9029bd28
RDX: ffffffff90ddb214 RSI: ffffffff90ddb214 RDI: ffffffff8be08580
RBP: dffffc0000000000 R08: 0000000000000003 R09: ffffffff8e13efa0
R10: ffffc90003c67218 R11: ffffffff81acb3b0 R12: ffffffff90ddb218
R13: ffffffff90ddb219 R14: ffffc90003c671c8 R15: ffffffff9029bd24
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5267 [inline]
 kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5274
 mt_alloc_one lib/maple_tree.c:174 [inline]
 mas_dup_build+0x141/0x1250 lib/maple_tree.c:6299
 __mt_dup+0x147/0x230 lib/maple_tree.c:6382
 dup_mmap+0x3b7/0x1b80 mm/mmap.c:1744
 dup_mm kernel/fork.c:1529 [inline]
 copy_mm+0x13c/0x4b0 kernel/fork.c:1581
 copy_process+0x1812/0x3ba0 kernel/fork.c:2218
 kernel_clone+0x21e/0x820 kernel/fork.c:2648
 __do_sys_clone kernel/fork.c:2789 [inline]
 __se_sys_clone kernel/fork.c:2773 [inline]
 __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2773
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5afb585e93
RSP: 002b:00007ffc0a3ecb48 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5afb585e93
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555930cd7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000ca701 R15: 00007ffc0a3ecce0
 </TASK>
rcu: rcu_preempt kthread starved for 10535 jiffies! g52217 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:27704 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5282 [inline]
 __schedule+0x14ed/0x5040 kernel/sched/core.c:6894
 __schedule_loop kernel/sched/core.c:6976 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6991
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x11b0 kernel/rcu/tree.c:2095
 rcu_gp_kthread+0x9b/0x2d0 kernel/rcu/tree.c:2297
 kthread+0x389/0x480 kernel/kthread.c:467
 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) 
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:82
Code: cc cc cc cc cc cc cc 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 43 5e 2b 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 000002c2
RAX: 00000000023071cb RBX: ffffffff8197171e RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d99f7ca RDI: ffffffff8be085e0
RBP: ffffc90000197f10 R08: ffff8880b873375b R09: 1ffff110170e66eb
R10: dffffc0000000000 R11: ffffed10170e66ec R12: ffffffff8fa24670
R13: 1ffff11003adab58 R14: 0000000000000001 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888125d0a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2e9a3b7198 CR3: 000000002929a000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x147
 </TASK>