multicore boot error: witness: reversal: vmmaplk inode

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: fc5790bacc0b don't deref pointer before test it is safe ok..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=1489def2700000
kernel config: https://syzkaller.appspot.com/x/.config?x=bf87b6915a88cd0d
dashboard link: https://syzkaller.appspot.com/bug?extid=7483f8f919db4852f664

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7483f8...@syzkaller.appspotmail.com

witness: lock order reversal:

1st 0xfffffd807efff8b8 vmmaplk (&map->lock)

2nd 0xfffffd806f67ce78 inode (&ip->i_lock)

lock order "&ip->i_lock"(rrwlock) -> "&map->lock"(rwlock) first seen at:

#0 rw_enter_read+0x66 sys/kern/kern_rwlock.c:112

#1 uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1758

#2 uvm_fault_check+0x3a sys/uvm/uvm_fault.c:674

#3 uvm_fault+0x102 sys/uvm/uvm_fault.c:602

#4 kpageflttrap+0x209

#5 kerntrap+0xef sys/arch/amd64/amd64/trap.c:318

#6 alltraps_kern_meltdown+0x7b

#7 copyout+0x53

#8 ffs_read+0x3c2 sys/ufs/ffs/ffs_vnops.c:258

#9 VOP_READ+0xbf sys/kern/vfs_vops.c:227

#10 vn_rdwr+0x105

#11 vmcmd_map_readvn+0xd4 sys/kern/exec_subr.c:246

#12 exec_process_vmcmds+0xc2 sys/kern/exec_subr.c:143

#13 sys_execve+0x8fa sys/kern/kern_exec.c:462

#14 syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline]

#14 syscall+0x489 sys/arch/amd64/amd64/trap.c:585

#15 Xsyscall+0x128

lock order data w1 -> w2 missing

Stopped at db_enter+0x18: addq $0x8,%rsp

ddb{1}>


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[Anton Lindqvist]

#syz invalid