low hanging fruit (was Re: HVM disc corruption (was Re: Xen won't start its device backend?))

[Reinoud Zandijk <reinoud%NetBSD.org@localhost>]

On Wed, May 27, 2015 at 10:29:13PM +0200, Reinoud Zandijk wrote:
> I see that it uses qemu-dm and tries to use the raw device indeed:
>   ...
>   5111      1 qemu-dm  CALL  open(0xa9baa0,2,0x1a4)
>   5111      1 qemu-dm  NAMI  "/dev/rwd1d"
>   5111      1 qemu-dm  RET   open 16/0x10
>   5111      1 qemu-dm  CALL  __fstat50(0x10,0x7f7fffffc560)
>   5111      1 qemu-dm  RET   __fstat50 0
>   5111      1 qemu-dm  CALL  ioctl(0x10,DIOCGWEDGEINFO,0x7f7fffffc2f0)
>   5111      1 qemu-dm  RET   ioctl -1 errno 25 Inappropriate ioctl for device
>   5111      1 qemu-dm  CALL  ioctl(0x10,DIOCGDINFO,0x7f7fffffc3c0)
>   5111      1 qemu-dm  GIO   fd 16 read 408 bytes

And it calls this DIOCGWEDGEINFO in the short time that i monitored until it
failed to read init a shocking 75692 times (!)