uvm_fault: db_enter (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: be93862e1464 make the CPU frequency scaling duration relat..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=15bce349f00000
kernel config: https://syzkaller.appspot.com/x/.config?x=bf87b6915a88cd0d
dashboard link: https://syzkaller.appspot.com/bug?extid=25f69433269c3016dd8f

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+25f694...@syzkaller.appspotmail.com

uvm_fault(fffffd80734ef478,19a27d27000,0,2) at uvm_fault+0x164 sys/uvm/uvm_fault.c:610
upageflttrap(ffff800027b0b4d0,19a27d27ff2) at upageflttrap+0x82 sys/arch/amd64/amd64/trap.c:181
usertrap(ffff800027b0b4d0) at usertrap+0x1aa sys/arch/amd64/amd64/trap.c:403
recall_trap() at recall_trap+0x8
end of kernel
end trace frame: 0x7f7ffffce610, count: -13
ddb{0}> machine ddbcpu 1
Stopped at db_enter+0x18: addq $0x8,%rsp
ddb{1}> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437
witness_checkorder(fffffd8063f7de70,9,0) at witness_checkorder+0x10b7 witness_debugger sys/kern/subr_witness.c:2502 [inline]
witness_checkorder(fffffd8063f7de70,9,0) at witness_checkorder+0x10b7 sys/kern/subr_witness.c:1105
rw_enter(fffffd8063f7de60,1) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250
rrw_enter(fffffd8063f7de60,1) at rrw_enter+0x8b sys/kern/kern_rwlock.c:465
VOP_LOCK(fffffd8065ec9770,2001) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:534
vn_lock(fffffd8065ec9770,2001) at vn_lock+0x84 sys/kern/vfs_vnops.c:579
vn_rdwr(0,fffffd8065ec9770,ffff8000089432c0,29,0,1,a5e60ed0755250e9,ffff8000006b6000,fffffd805d0795e0,0) at vn_rdwr+0xb1 sys/kern/vfs_vnops.c:326
vndstrategy(fffffd805d0795e0) at vndstrategy+0x3c4 sys/dev/vnd.c:342
physio(ffffffff81fc0810,2902,8000,ffffffff815838f0,ffff80002e47dac0) at physio+0x289 sys/kern/kern_physio.c:163
spec_read(ffff80002e47d8a0) at spec_read+0xf5 sys/kern/spec_vnops.c:222
VOP_READ(fffffd805b0f9b60,ffff80002e47dac0,0,fffffd807f7d76c0) at VOP_READ+0xbf sys/kern/vfs_vops.c:227
vn_read(fffffd80686f30b0,ffff80002e47dac0,0) at vn_read+0x126 sys/kern/vfs_vnops.c:375
dofilereadv(ffff80002122f260,3,ffff80002e47dac0,0,ffff80002e47dbc0) at dofilereadv+0x19e sys/kern/sys_generic.c:253
sys_readv(ffff80002122f260,ffff80002e47db68,ffff80002e47dbc0) at sys_readv+0xa7 sys/kern/sys_generic.c:200
syscall(ffff80002e47dc30) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff80002e47dc30) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x51591ed1c00, count: -16


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[Anton Lindqvist]

#syz invalid