uvm_fault: db_enter (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8bcd09c7700c drm/i915/dsi: fix VBT send packet port select..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=17b994fdf00000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=81935104ab719ec7e2db

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+819351...@syzkaller.appspotmail.com

uvm_fault(fffffd806ee67738,c001d8e000,0,2) at uvm_fault+0x102 sys/uvm/uvm_fault.c:602
upageflttrap(ffff8000212101a0,c001d8e060) at upageflttrap+0x82 sys/arch/amd64/amd64/trap.c:181
usertrap(ffff8000212101a0) at usertrap+0x1aa sys/arch/amd64/amd64/trap.c:403
recall_trap() at recall_trap+0x8
end of kernel
end trace frame: 0xc002b1f658, count: -14
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(fffffd8075b680a0,9,0) at witness_checkorder+0x10b7 witness_debugger sys/kern/subr_witness.c:2502 [inline]
witness_checkorder(fffffd8075b680a0,9,0) at witness_checkorder+0x10b7 sys/kern/subr_witness.c:1105
rw_enter(fffffd8075b68090,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250
rrw_enter(fffffd8075b68090,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:465
VOP_LOCK(fffffd8068faa390,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:534
vn_lock(fffffd8068faa390,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579
uvn_io(fffffd807db20248,ffff8000274e3270,1,2b,1) at uvn_io+0x338 sys/uvm/uvm_vnode.c:1236
uvm_pager_put(fffffd807db20248,fffffd8008109e20,ffff8000274e3308,ffff8000274e3348,2b,0,cb4ff3673f0aeca7) at uvm_pager_put+0x137 sys/uvm/uvm_pager.c:523
uvn_flush(fffffd807db20248,0,3000,b) at uvn_flush+0x532 sys/uvm/uvm_vnode.c:723
uvm_map_clean(fffffd807d067a10,20000000,20004000,b) at uvm_map_clean+0x72b sys/uvm/uvm_map.c:4788
syscall(ffff8000274e3540) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff8000274e3540) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x47ad5478350, count: -12


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[Anton Lindqvist]

#syz invalid