Re: [Qemu-devel] [SeaBIOS] [SeaBIOS PATCH] boot: fix fw_dev_path pattern for q35-pcihost

[Gleb Natapov <gleb@redhat.com>]

On Wed, May 29, 2013 at 10:33:54AM +0800, Amos Kong wrote:
> On Tue, May 28, 2013 at 06:59:02PM -0400, Kevin O'Connor wrote:
> > On Tue, May 28, 2013 at 08:28:14PM +0800, Amos Kong wrote:
> > > Bootindex string passed from qemu:
> > >  /q35-pcihost@i0cf8/ethernet@2/ethernet-phy@0
> > > 
> > > We match pci domain by "/pci@i0cf8" in SeaBIOS, but fw_dev_path prefix
> > > of q35 is "/q35-pcihost@i0cf8". So bootindex in qemu commandline
> > > doesn't work if it uses q35 machine type.
> > > 
> > > This patch fixes the pattern to match both original pc-i440fx & q35
> > > 
> > > Signed-off-by: Amos Kong <akong@redhat.com>
> > > ---
> > >  src/boot.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/src/boot.c b/src/boot.c
> > > index cd9d784..f30d47e 100644
> > > --- a/src/boot.c
> > > +++ b/src/boot.c
> > > @@ -97,7 +97,7 @@ find_prio(const char *glob)
> > >      return -1;
> > >  }
> > >  
> > > -#define FW_PCI_DOMAIN "/pci@i0cf8"
> > > +#define FW_PCI_DOMAIN "/*pci*@i0cf8"
> > 
> > The seabios pattern matching code isn't that sophisticated - I think
> > this could end up doing something unexpected.  Why does it need to
> > change?
> 
> If we start a guest with default machine type (pc-i440fx), the prefix
> of bootindex string is "/pci@i0cf8", if we start guest with -M q35,
> the prefix will become "/q35-pcihost@i0cf8".
> 
> We only match "/pci@i0cf8" in seabios, it causes boot priority of q35
> devices could not be changed.
> 
> We could not change TYPE_Q35_HOST_DEVICE to 'pci' in qemu to adapt
> seabios, so fix the pattern.
> 
Why couldn't we? QEMU not been able to generate proper device string is
QEMU bug.

--
			Gleb.