rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7832/1:b..l
	(detected by 0, t=10502 jiffies, g=37669, q=186 ncpus=2)
task:syz.6.911       state:R  running task     stack:25824 pid:7832  ppid:7216   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696
RIP: 0010:get_page_owner mm/page_owner.c:106 [inline]
RIP: 0010:__reset_page_owner+0xbf/0x1a0 mm/page_owner.c:151
Code: 8c 00 00 00 e8 42 06 a6 ff 41 83 ee 01 0f 82 ba 00 00 00 e8 33 06 a6 ff 4c 89 ff be 08 00 00 00 e8 26 7b f7 ff 49 0f ba 37 01 <4c> 8b 2d 6a 7c c8 0a 4b 8d 7c 2f 0c 48 89 f8 48 c1 e8 03 42 0f b6
RSP: 0018:ffffc900033f72e8 EFLAGS: 00000257
RAX: ffffffff81dacd01 RBX: 1ffffffff1947254 RCX: ffffffff81dacd8a
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88801ad13148
RBP: 0000000000000003 R08: dffffc0000000000 R09: ffffed10035a262a
R10: ffffed10035a262a R11: 1ffff110035a2629 R12: dffffc0000000000
R13: ffff88801ad13120 R14: 0000000000000006 R15: ffff88801ad13148
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1459 [inline]
 free_pcp_prepare mm/page_alloc.c:1509 [inline]
 free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384
 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479
 free_slab mm/slub.c:2031 [inline]
 discard_slab mm/slub.c:2037 [inline]
 __unfreeze_partials+0x1a5/0x200 mm/slub.c:2586
 put_cpu_partial+0x17c/0x250 mm/slub.c:2662
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3422
 ptlock_alloc+0x1c/0x60 mm/memory.c:6047
 ptlock_init include/linux/mm.h:2415 [inline]
 pgtable_pte_page_ctor include/linux/mm.h:2442 [inline]
 __pte_alloc_one include/asm-generic/pgalloc.h:66 [inline]
 pte_alloc_one+0xc5/0x2f0 arch/x86/mm/pgtable.c:33
 do_fault_around mm/memory.c:4595 [inline]
 do_read_fault mm/memory.c:4626 [inline]
 do_fault mm/memory.c:4760 [inline]
 handle_pte_fault mm/memory.c:5031 [inline]
 __handle_mm_fault mm/memory.c:5173 [inline]
 handle_mm_fault+0x280a/0x3e70 mm/memory.c:5294
 do_user_addr_fault+0x51f/0xb10 arch/x86/mm/fault.c:1340
 handle_page_fault arch/x86/mm/fault.c:1431 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1487
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0010:copy_user_short_string+0xa/0x40 arch/x86/lib/copy_user_64.S:232
Code: 83 f8 12 74 0a 89 d1 f3 a4 89 c8 0f 01 ca c3 89 d0 0f 01 ca c3 01 ca eb e7 90 90 90 90 90 90 90 89 d1 83 e2 07 c1 e9 03 74 12 <4c> 8b 06 4c 89 07 48 8d 76 08 48 8d 7f 08 ff c9 75 ee 21 d2 74 10
RSP: 0018:ffffc900033f7a48 EFLAGS: 00050202
RAX: ffffffff8407a201 RBX: 0000000000000038 RCX: 0000000000000007
RDX: 0000000000000000 RSI: 0000200000033000 RDI: ffffc900033f7ae0
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff5200067ef63
R10: fffff5200067ef63 R11: 1ffff9200067ef5c R12: 00007fffffffefc8
R13: dffffc0000000000 R14: ffffc900033f7ae0 R15: 0000200000033000
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline]
 _copy_from_user+0xf4/0x170 lib/usercopy.c:23
 copy_from_user include/linux/uaccess.h:161 [inline]
 copy_msghdr_from_user net/socket.c:2449 [inline]
 recvmsg_copy_msghdr net/socket.c:2704 [inline]
 ___sys_recvmsg+0x12b/0x510 net/socket.c:2776
 do_recvmmsg+0x359/0x7d0 net/socket.c:2874
 __sys_recvmmsg net/socket.c:2953 [inline]
 __do_sys_recvmmsg net/socket.c:2976 [inline]
 __se_sys_recvmmsg net/socket.c:2969 [inline]
 __x64_sys_recvmmsg+0x18d/0x240 net/socket.c:2969
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9ad978e969
RSP: 002b:00007f9ada653038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f9ad99b6080 RCX: 00007f9ad978e969
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 000000000000000d
RBP: 00007f9ad9810ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f9ad99b6080 R15: 00007ffc9a7a39f8
 </TASK>
rcu: rcu_preempt kthread starved for 9822 jiffies! g37669 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:26912 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 1 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:735