Re: [Qemu-devel] [PATCH 1/5] xen: drop support for Xen 4.1 and older.

[Ian Campbell <ian.campbell@citrix.com>]

On Tue, 2016-02-09 at 16:50 +0000, Stefano Stabellini wrote:
> > @@ -2218,15 +2127,10 @@ EOF
> >  fi
> >  
> >  if test "$xen_pci_passthrough" != "no"; then
> > -  if test "$xen" = "yes" && test "$linux" = "yes" &&
> > -    test "$xen_ctrl_version" -ge 340; then
> > +  if test "$xen" = "yes" && test "$linux" = "yes"; then
> >      xen_pci_passthrough=yes
> >    else
> >      if test "$xen_pci_passthrough" = "yes"; then
> 
> Given that the code has been greatly simplified, I think that we can get
> rid of the test above.

Which one? I think we still need to check for both Linux and Xen being
present and handle users passing --enable-xen-pci-passthrough when those
conditions don't hold.

It might be possible to fold the else if, i.e. 

if test "$xen_pci_passthrough" != "no"; then
  if test "$xen" = "yes" && test "$linux" = "yes"; then
    xen_pci_passthrough=yes
  elif test "$xen_pci_passthrough" = "yes"; then
    error_exit "User requested feature Xen PCI Passthrough" \
        " but this feature requires /sys from Linux"
  else
    xen_pci_passthrough=no
  fi
fi

?