rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6201/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=13321, q=54 ncpus=2)
task:syz.3.62        state:R  running task     stack:25864 pid:6201  tgid:6197  ppid:5809   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0x1553/0x5240 kernel/sched/core.c:6911
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7238
 irqentry_exit+0x599/0x620 kernel/entry/common.c:239
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x20b/0x2e0 kernel/locking/lockdep.c:5872
Code: e9 30 ff ff ff e8 e5 9a 82 09 f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 51 08 ae 10 48 3b 44 24 30 75 33 fb 48 83 c4 38 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 3e 28 cd
RSP: 0018:ffffc90005da7658 EFLAGS: 00000282
RAX: c3bcb221a05f4200 RBX: 0000000000000246 RCX: 0000000000000046
RDX: 0000000002f62cf4 RSI: ffffffff8d7bd351 RDI: ffffffff8ba66700
RBP: 0000000000000000 R08: ffffffff82118471 R09: ffffffff8ddcb980
R10: dffffc0000000000 R11: fffffbfff1ed4797 R12: 0000000000000002
R13: ffffffff8ddcb980 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 rcu_read_lock include/linux/rcupdate.h:850 [inline]
 count_memcg_events_mm include/linux/memcontrol.h:983 [inline]
 count_memcg_event_mm+0x3d/0x260 include/linux/memcontrol.h:993
 mm_account_fault mm/memory.c:6489 [inline]
 handle_mm_fault+0x11d6/0x13c0 mm/memory.c:6650
 do_user_addr_fault+0x75b/0x1340 arch/x86/mm/fault.c:1385
 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: 0010:rep_movs_alternative+0x30/0x90 arch/x86/lib/copy_user_64.S:60
Code: 83 f9 08 73 25 85 c9 74 0f 8a 06 88 07 48 ff c7 48 ff c6 48 ff c9 75 f1 c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 <48> 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 db 83 f9 08
RSP: 0018:ffffc90005da7a18 EFLAGS: 00050206
RAX: 00007ffffffff001 RBX: 0000000000000038 RCX: 0000000000000038
RDX: 0000000000000001 RSI: 000020000022b000 RDI: ffffc90005da7aa0
RBP: ffffc90005da7c30 R08: ffffc90005da7ad7 R09: 1ffff92000bb4f5a
R10: dffffc0000000000 R11: fffff52000bb4f5b R12: ffffc90005da7ba0
R13: dffffc0000000000 R14: ffffc90005da7aa0 R15: 000020000022b000
 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline]
 _inline_copy_from_user include/linux/uaccess.h:185 [inline]
 _copy_from_user+0x7a/0xb0 lib/usercopy.c:18
 copy_from_user include/linux/uaccess.h:223 [inline]
 copy_msghdr_from_user net/socket.c:2522 [inline]
 recvmsg_copy_msghdr net/socket.c:2778 [inline]
 ___sys_recvmsg+0x175/0x590 net/socket.c:2850
 do_recvmmsg+0x33a/0x800 net/socket.c:2949
 __sys_recvmmsg net/socket.c:3023 [inline]
 __do_sys_recvmmsg net/socket.c:3046 [inline]
 __se_sys_recvmmsg net/socket.c:3039 [inline]
 __x64_sys_recvmmsg+0x198/0x250 net/socket.c:3039
 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: 0033:0x7f70fcc1c799
RSP: 002b:00007f70fae55028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f70fce96090 RCX: 00007f70fcc1c799
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f70fccb2c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f70fce96128 R14: 00007f70fce96090 R15: 00007ffc251d3d08
 </TASK>
rcu: rcu_preempt kthread starved for 10502 jiffies! g13321 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:27776 pid:18    tgid:18    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0x1553/0x5240 kernel/sched/core.c:6911
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7008
 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 6e 5d 02 e9 13 c4 03 00 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 f3 9c 26 00 fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffffff8da07dc0 EFLAGS: 00000242
RAX: 00000000000d95f1 RBX: ffffffff81996dba RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d560db4 RDI: ffffffff8ba66700
RBP: ffffffff8da07eb0 R08: ffff8880b8833f1b R09: 1ffff110171067e3
R10: dffffc0000000000 R11: ffffed10171067e4 R12: ffffffff8f6a3cb0
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1b605d8
FS:  0000000000000000(0000) GS:ffff88812633c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000003a280000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/kernel/process.c:766 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1ba/0x5d0 kernel/sched/idle.c:341
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:439
 rest_init+0x2de/0x300 init/main.c:760
 start_kernel+0x385/0x3d0 init/main.c:1210
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x147
 </TASK>