syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P9415/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=30485, q=118 ncpus=2)
task:syz.1.862       state:R  running task     stack:25864 pid:9415  tgid:9409  ppid:5822   task_flags:0x400040 flags:0x00080003
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6929
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7256
 irqentry_exit+0x36/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__sanitizer_cov_trace_switch+0x12/0x90 kernel/kcov.c:331
Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 56 41 55 41 54 49 89 fc 55 48 89 f5 53 <48> 8b 46 08 48 83 f8 20 74 6b 77 48 48 83 f8 08 74 5b 48 83 f8 10
RSP: 0018:ffffc9000532f638 EFLAGS: 00000206
RAX: 0000000000000003 RBX: 0000000000000003 RCX: ffffc9000dea9000
RDX: ffff88801e2df800 RSI: ffffffff8cf04d60 RDI: 0000000000000003
RBP: ffffffff8cf04d60 R08: 0000000000000005 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000003
R13: ffffc9000532f858 R14: ffffc9000532f778 R15: 0000000000000002
 ma_pivots lib/maple_tree.c:600 [inline]
 mtree_range_walk+0x314/0xc00 lib/maple_tree.c:2555
 mas_state_walk lib/maple_tree.c:3296 [inline]
 mt_find+0x4c5/0xa20 lib/maple_tree.c:6495
 find_vma+0xbf/0x140 mm/mmap.c:909
 lock_mm_and_find_vma+0x62/0x6e0 mm/mmap_lock.c:431
 do_user_addr_fault+0x2ac/0x1370 arch/x86/mm/fault.c:1359
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532
 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 e9 4d 3c 04 00 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 <48> 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 db 83 f9 08
RSP: 0018:ffffc9000532fa48 EFLAGS: 00050206
RAX: 0000000000000001 RBX: 0000200000351000 RCX: 0000000000000038
RDX: fffff52000a65f5a RSI: 0000200000351000 RDI: ffffc9000532fa98
RBP: 0000000000000038 R08: 0000000000000001 R09: fffff52000a65f59
R10: ffffc9000532facf R11: 0000000000000001 R12: 0000000000000000
R13: ffffc9000532fa98 R14: ffffc9000532fb80 R15: ffffc9000532fa98
 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:178 [inline]
 _copy_from_user+0x98/0xd0 lib/usercopy.c:18
 copy_from_user include/linux/uaccess.h:212 [inline]
 copy_msghdr_from_user+0x98/0x160 net/socket.c:2560
 recvmsg_copy_msghdr net/socket.c:2816 [inline]
 ___sys_recvmsg+0xdb/0x1a0 net/socket.c:2888
 do_recvmmsg+0x2fe/0x750 net/socket.c:2987
 __sys_recvmmsg net/socket.c:3061 [inline]
 __do_sys_recvmmsg net/socket.c:3084 [inline]
 __se_sys_recvmmsg net/socket.c:3077 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3077
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0b7318efc9
RSP: 002b:00007f0b73ff7038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f0b733e6090 RCX: 00007f0b7318efc9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000006
RBP: 00007f0b73211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0b733e6128 R14: 00007f0b733e6090 R15: 00007ffdb7d3d1e8
 </TASK>