rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P18016/1:b..l P18021/1:b..l P18024/1:b..l P5187/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=130701, q=1404 ncpus=2)
task:klogd           state:R  running task     stack:22952 pid:5187  tgid:5187  ppid:1      task_flags:0x400100 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5392 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6961
 preempt_schedule+0xae/0xc0 kernel/sched/core.c:6985
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0xfd/0x110 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 __wake_up_common_lock+0x190/0x1f0 kernel/sched/wait.c:108
 sock_def_readable+0x1fb/0x550 net/core/sock.c:3583
 unix_dgram_sendmsg+0xd94/0x1870 net/unix/af_unix.c:2224
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:727
 __sys_sendto+0x3bd/0x520 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2183
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f26d300a407
RSP: 002b:00007fffe2905ed0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f26d2ebac80 RCX: 00007f26d300a407
RDX: 000000000000005f RSI: 00007fffe2906010 RDI: 0000000000000003
RBP: 00007fffe2906440 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000202 R12: 00007fffe2906458
R13: 00007fffe2906010 R14: 0000000000000044 R15: 00007fffe2906010
 </TASK>
task:kworker/u8:1    state:R  running task     stack:26920 pid:18024 tgid:18024 ppid:13     task_flags:0x8040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5392 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7104
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:unwind_next_frame+0x1174/0x2390 arch/x86/kernel/unwind_orc.c:641
Code: 8b 14 24 4d 89 65 00 41 0f b6 04 2f 84 c0 0f 85 f9 0f 00 00 c6 03 00 4c 8b 64 24 10 4c 8b 7c 24 28 48 8b 44 24 40 0f b6 04 28 <84> c0 0f 85 8a 0d 00 00 41 0f b6 04 2f 84 c0 0f 85 a1 0d 00 00 0f
RSP: 0018:ffffc9000b9e7098 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffc9000b9e71a0 RCX: 0000000000000000
RDX: ffffffff903b3a92 RSI: 0000000000000000 RDI: ffffc9000b9e71c8
RBP: dffffc0000000000 R08: ffffc9000b9e71c7 R09: 0000000000000000
R10: ffffc9000b9e71b8 R11: fffff5200173ce39 R12: ffffc9000b9e7ba0
R13: ffffc9000b9e71b8 R14: ffffc9000b9e7168 R15: 1ffffffff2076752
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf5/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2716 [inline]
 __put_partials+0x161/0x1c0 mm/slub.c:3185
 put_cpu_partial+0x17c/0x250 mm/slub.c:3260
 __slab_free+0x2f7/0x400 mm/slub.c:4512
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4147 [inline]
 slab_alloc_node mm/slub.c:4196 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4203
 ptlock_alloc+0x20/0x70 mm/memory.c:7192
 ptlock_init include/linux/mm.h:2934 [inline]
 pagetable_pte_ctor include/linux/mm.h:2983 [inline]
 __pte_alloc_one_noprof include/asm-generic/pgalloc.h:78 [inline]
 pte_alloc_one+0x7d/0x170 arch/x86/mm/pgtable.c:18
 __pte_alloc+0x25/0x1a0 mm/memory.c:439
 do_anonymous_page mm/memory.c:5057 [inline]
 do_pte_missing mm/memory.c:4247 [inline]
 handle_pte_fault mm/memory.c:6087 [inline]
 __handle_mm_fault+0x4b8a/0x5620 mm/memory.c:6230
 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6399
 faultin_page mm/gup.c:1186 [inline]
 __get_user_pages+0x1af4/0x30b0 mm/gup.c:1488
 __get_user_pages_locked mm/gup.c:1754 [inline]
 get_user_pages_remote+0x2f9/0xaa0 mm/gup.c:2644
 get_arg_page+0x104/0x330 fs/exec.c:160
 copy_string_kernel+0x191/0x2a0 fs/exec.c:563
 kernel_execve+0x5a2/0x9f0 fs/exec.c:1902
 call_usermodehelper_exec_async+0x210/0x360 kernel/umh.c:109
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
task:syz.0.3404      state:R  running task     stack:25080 pid:18021 tgid:18019 ppid:17017  task_flags:0x400140 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5392 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7104
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:debug_lockdep_rcu_enabled+0x2a/0x40 kernel/rcu/update.c:321
Code: f3 0f 1e fa 31 c0 83 3d 27 2e 3c 04 00 74 1e 83 3d 4a 5e 3c 04 00 74 15 65 48 8b 0c 25 08 10 9c 92 31 c0 83 b9 ec 0a 00 00 00 <0f> 94 c0 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc
RSP: 0018:ffffc9000b94ef10 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff903d2701 RCX: ffff88802fa9bc00
RDX: ffffc9000b94f001 RSI: dffffc0000000000 RDI: ffffc9000b94eff0
RBP: dffffc0000000000 R08: ffffc9000b94f460 R09: 0000000000000000
R10: ffffc9000b94f038 R11: fffff52001729e09 R12: ffffc9000b94f470
R13: ffffc9000b948000 R14: ffffc9000b94efe8 R15: ffffffff81727e15
 rcu_read_unlock include/linux/rcupdate.h:869 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0x195c/0x2390 arch/x86/kernel/unwind_orc.c:680
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf5/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2716 [inline]
 __put_partials+0x161/0x1c0 mm/slub.c:3185
 put_cpu_partial+0x17c/0x250 mm/slub.c:3260
 __slab_free+0x2f7/0x400 mm/slub.c:4512
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:385
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358
 kmalloc_noprof include/linux/slab.h:905 [inline]
 call_modprobe kernel/module/kmod.c:83 [inline]
 __request_module+0x2b5/0x5e0 kernel/module/kmod.c:172
 crypto_larval_lookup crypto/api.c:302 [inline]
 crypto_alg_mod_lookup+0xa5/0x5f0 crypto/api.c:353
 crypto_has_alg+0x26/0x190 crypto/api.c:692
 crypto_has_acomp include/crypto/acompress.h:229 [inline]
 xfrm_probe_algs+0x301/0x360 net/xfrm/xfrm_algo.c:831
 pfkey_register+0x113/0x890 net/key/af_key.c:1701
 pfkey_process net/key/af_key.c:2848 [inline]
 pfkey_sendmsg+0xbfe/0x1090 net/key/af_key.c:3699
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:727
 ____sys_sendmsg+0x505/0x830 net/socket.c:2566
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620
 __sys_sendmsg net/socket.c:2652 [inline]
 __do_sys_sendmsg net/socket.c:2657 [inline]
 __se_sys_sendmsg net/socket.c:2655 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2655
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1e0638e969
RSP: 002b:00007f1e071b8038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1e065b6080 RCX: 00007f1e0638e969
RDX: 0000000000000000 RSI: 0000200000000000 RDI: 000000000000000c
RBP: 00007f1e06410ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f1e065b6080 R15: 00007f1e066dfa28
 </TASK>
task:syz.1.3403      state:R  running task     stack:25304 pid:18016 tgid:18014 ppid:16166  task_flags:0x40054c flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5392 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6961
 preempt_schedule+0xae/0xc0 kernel/sched/core.c:6985
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 zap_pte_range mm/memory.c:1763 [inline]
 zap_pmd_range mm/memory.c:1825 [inline]
 zap_pud_range mm/memory.c:1854 [inline]
 zap_p4d_range mm/memory.c:1875 [inline]
 unmap_page_range+0x38e5/0x4580 mm/memory.c:1896
 unmap_single_vma mm/memory.c:1939 [inline]
 unmap_vmas+0x399/0x580 mm/memory.c:1983
 exit_mmap+0x248/0xb50 mm/mmap.c:1284
 __mmput+0x118/0x420 kernel/fork.c:1121
 exit_mm+0x1da/0x2c0 kernel/exit.c:581
 do_exit+0x640/0x22e0 kernel/exit.c:943
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1104
 get_signal+0x1286/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f978338e969
RSP: 002b:00007f978414e038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffff8d RBX: 00007f97835b5fa0 RCX: 00007f978338e969
RDX: 000000000000001c RSI: 00002000000001c0 RDI: 0000000000000003
RBP: 00007f9783410ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f97835b5fa0 R15: 00007f97836dfa28
 </TASK>
rcu: rcu_preempt kthread starved for 8418 jiffies! g130701 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:27224 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5392 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6961
 preempt_schedule+0xae/0xc0 kernel/sched/core.c:6985
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0xfd/0x110 kernel/locking/spinlock.c:194
 __mod_timer+0xb37/0xf30 kernel/time/timer.c:1139
 schedule_timeout+0x126/0x270 kernel/time/sleep_timeout.c:98
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.15.0-syzkaller-10769-g7d4e49a77d99 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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 e3 a0 23 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:ffffffff8de07d80 EFLAGS: 000002c2
RAX: 0716413ee9c0ed00 RBX: ffffffff81973de8 RCX: 0716413ee9c0ed00
RDX: 0000000000000001 RSI: ffffffff8d9705da RDI: ffffffff8be26f40
RBP: ffffffff8de07ea8 R08: ffff8880b8632f5b R09: 1ffff110170c65eb
R10: dffffc0000000000 R11: ffffed10170c65ec R12: ffffffff8fa0bcf0
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1bd2a50
FS:  0000000000000000(0000) GS:ffff888125c5f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fda058600a8 CR3: 0000000023732000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:743
 default_idle_call+0x74/0xb0 kernel/sched/idle.c:117
 cpuidle_idle_call kernel/sched/idle.c:185 [inline]
 do_idle+0x1e8/0x510 kernel/sched/idle.c:325
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423
 rest_init+0x2de/0x300 init/main.c:744
 start_kernel+0x47d/0x500 init/main.c:1101
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307
 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288
 common_startup_64+0x13e/0x147
 </TASK>