Hi developers, I just discovered that with gfx-passthrough=1, the iPXE simply does not work. It seems that no NIC is detected by iPXE -- ifstat shows nothing. I''m on xen-4.2.1 release, with some IGD passthrough related patches. I would like to check if this is a common issue, can anybody help? Thanks, Timothy
Hi Stefano, Do you familiar with this part? Thanks, Timothy On Wed, Apr 10, 2013 at 9:54 PM, G.R. <firemeteor@users.sourceforge.net> wrote:> Hi developers, > > I just discovered that with gfx-passthrough=1, the iPXE simply does not work. > It seems that no NIC is detected by iPXE -- ifstat shows nothing. > I''m on xen-4.2.1 release, with some IGD passthrough related patches. > I would like to check if this is a common issue, can anybody help? > > Thanks, > Timothy
Can anybody help? On Wed, Apr 10, 2013 at 11:50 PM, G.R. <firemeteor@users.sourceforge.net> wrote:> Hi Stefano, > Do you familiar with this part? > > Thanks, > Timothy > > On Wed, Apr 10, 2013 at 9:54 PM, G.R. <firemeteor@users.sourceforge.net> wrote: >> Hi developers, >> >> I just discovered that with gfx-passthrough=1, the iPXE simply does not work. >> It seems that no NIC is detected by iPXE -- ifstat shows nothing. >> I''m on xen-4.2.1 release, with some IGD passthrough related patches. >> I would like to check if this is a common issue, can anybody help? >> >> Thanks, >> Timothy
A quick update about the root cause of this issue: The rombios BIOS used in xen restrict itself to i440FX emulated by Bochs / qemu. With gfx-passthrough, the pci-host bridge in the domU is replaced by the device in the host machine. This makes PCI emulation fail. The issue can be fixed by simply commenting out this line: diff --git a/tools/firmware/rombios/rombios.c b/tools/firmware/rombios/rombios.c index 80980b6..e9c5c4a 100644 --- a/tools/firmware/rombios/rombios.c +++ b/tools/firmware/rombios/rombios.c @@ -220,7 +220,7 @@ // define this if you want to make PCIBIOS working on a specific bridge only // undef enables PCIBIOS when at least one PCI device is found // i440FX is emulated by Bochs and QEMU -#define PCI_FIXED_HOST_BRIDGE 0x12378086 ;; i440FX PCI bridge +//#define PCI_FIXED_HOST_BRIDGE 0x12378086 ;; i440FX PCI bridge // #20 is dec 20 // #$20 is hex 20 = 32 On Wed, Apr 10, 2013 at 9:54 PM, G.R. <firemeteor@users.sourceforge.net> wrote:> Hi developers, > > I just discovered that with gfx-passthrough=1, the iPXE simply does not work. > It seems that no NIC is detected by iPXE -- ifstat shows nothing. > I''m on xen-4.2.1 release, with some IGD passthrough related patches. > I would like to check if this is a common issue, can anybody help? > > Thanks, > Timothy
On Wed, Aug 07, 2013 at 06:12:57PM +0800, G.R. wrote:> A quick update about the root cause of this issue: > The rombios BIOS used in xen restrict itself to i440FX emulated by Bochs / qemu. > With gfx-passthrough, the pci-host bridge in the domU is replaced by > the device in the host machine. > This makes PCI emulation fail. > The issue can be fixed by simply commenting out this line: > > diff --git a/tools/firmware/rombios/rombios.c b/tools/firmware/rombios/rombios.c > index 80980b6..e9c5c4a 100644 > --- a/tools/firmware/rombios/rombios.c > +++ b/tools/firmware/rombios/rombios.c > @@ -220,7 +220,7 @@ > // define this if you want to make PCIBIOS working on a specific bridge only > // undef enables PCIBIOS when at least one PCI device is found > // i440FX is emulated by Bochs and QEMU > -#define PCI_FIXED_HOST_BRIDGE 0x12378086 ;; i440FX PCI bridge > +//#define PCI_FIXED_HOST_BRIDGE 0x12378086 ;; i440FX PCI bridge > > // #20 is dec 20 > // #$20 is hex 20 = 32 >Thanks for the analysis and the workaround! I wonder what kind of side-effects this has (might have).. disabling the fixed i440FX host bridge.. I assume in your case there was no other issues introduced by the change? And PXE boot started working with PCI/GPU passthru.. -- Pasi> > On Wed, Apr 10, 2013 at 9:54 PM, G.R. <firemeteor@users.sourceforge.net> wrote: > > Hi developers, > > > > I just discovered that with gfx-passthrough=1, the iPXE simply does not work. > > It seems that no NIC is detected by iPXE -- ifstat shows nothing. > > I''m on xen-4.2.1 release, with some IGD passthrough related patches. > > I would like to check if this is a common issue, can anybody help? > > > > Thanks, > > Timothy > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel
On Wed, Aug 7, 2013 at 7:20 PM, Pasi Kärkkäinen <pasik@iki.fi> wrote:> On Wed, Aug 07, 2013 at 06:12:57PM +0800, G.R. wrote: >> A quick update about the root cause of this issue: >> The rombios BIOS used in xen restrict itself to i440FX emulated by Bochs / qemu. >> With gfx-passthrough, the pci-host bridge in the domU is replaced by >> the device in the host machine. >> This makes PCI emulation fail. >> The issue can be fixed by simply commenting out this line: >> >> diff --git a/tools/firmware/rombios/rombios.c b/tools/firmware/rombios/rombios.c >> index 80980b6..e9c5c4a 100644 >> --- a/tools/firmware/rombios/rombios.c >> +++ b/tools/firmware/rombios/rombios.c >> @@ -220,7 +220,7 @@ >> // define this if you want to make PCIBIOS working on a specific bridge only >> // undef enables PCIBIOS when at least one PCI device is found >> // i440FX is emulated by Bochs and QEMU >> -#define PCI_FIXED_HOST_BRIDGE 0x12378086 ;; i440FX PCI bridge >> +//#define PCI_FIXED_HOST_BRIDGE 0x12378086 ;; i440FX PCI bridge >> >> // #20 is dec 20 >> // #$20 is hex 20 = 32 >> > > Thanks for the analysis and the workaround! > > I wonder what kind of side-effects this has (might have).. disabling the fixed i440FX host bridge.. > I assume in your case there was no other issues introduced by the change? And PXE boot started working with PCI/GPU passthru.. > > -- PasiThere should be no negative side-effect. This is only a self restriction that disable PCIBIOS on unknown HW platform. Not sure why this is introduced in the first place.> >> >> On Wed, Apr 10, 2013 at 9:54 PM, G.R. <firemeteor@users.sourceforge.net> wrote: >> > Hi developers, >> > >> > I just discovered that with gfx-passthrough=1, the iPXE simply does not work. >> > It seems that no NIC is detected by iPXE -- ifstat shows nothing. >> > I''m on xen-4.2.1 release, with some IGD passthrough related patches. >> > I would like to check if this is a common issue, can anybody help? >> > >> > Thanks, >> > Timothy >> >> _______________________________________________ >> Xen-devel mailing list >> Xen-devel@lists.xen.org >> http://lists.xen.org/xen-devel
On Wed, Aug 7, 2013 at 11:12 AM, G.R. <firemeteor@users.sourceforge.net> wrote:> A quick update about the root cause of this issue: > The rombios BIOS used in xen restrict itself to i440FX emulated by Bochs / qemu. > With gfx-passthrough, the pci-host bridge in the domU is replaced by > the device in the host machine. > This makes PCI emulation fail. > The issue can be fixed by simply commenting out this line: > > diff --git a/tools/firmware/rombios/rombios.c b/tools/firmware/rombios/rombios.c > index 80980b6..e9c5c4a 100644 > --- a/tools/firmware/rombios/rombios.c > +++ b/tools/firmware/rombios/rombios.c > @@ -220,7 +220,7 @@ > // define this if you want to make PCIBIOS working on a specific bridge only > // undef enables PCIBIOS when at least one PCI device is found > // i440FX is emulated by Bochs and QEMU > -#define PCI_FIXED_HOST_BRIDGE 0x12378086 ;; i440FX PCI bridge > +//#define PCI_FIXED_HOST_BRIDGE 0x12378086 ;; i440FX PCI bridge > > // #20 is dec 20 > // #$20 is hex 20 = 32Ian, is this in your territory? -George