| Message ID | 4d4b58473beb0565876687e9d8a53b76a7cf3fbb.1655490576.git.brchuckz@aol.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] xen/pass-through: don't create needless register group | expand |
On Fri, Jun 17, 2022 at 03:13:33PM -0400, Chuck Zmudzinski wrote: > Currently we are creating a register group for the Intel IGD OpRegion > for every device we pass through, but the XEN_PCI_INTEL_OPREGION > register group is only valid for an Intel IGD. Add a check to make > sure the device is an Intel IGD and a check that the administrator has > enabled gfx_passthru in the xl domain configuration. Require both checks > to be true before creating the register group. Use the existing > is_igd_vga_passthrough() function to check for a graphics device from > any vendor and that the administrator enabled gfx_passthru in the xl > domain configuration, but further require that the vendor be Intel, > because only Intel IGD devices have an Intel OpRegion. These are the > same checks hvmloader and libxl do to determine if the Intel OpRegion > needs to be mapped into the guest's memory. Also, move the comment > about trapping 0xfc for the Intel OpRegion where it belongs after > applying this patch. > > Signed-off-by: Chuck Zmudzinski <brchuckz@aol.com> Reviewed-by: Anthony PERARD <anthony.perard@citrix.com> Thanks,
diff --git a/hw/xen/xen_pt_config_init.c b/hw/xen/xen_pt_config_init.c index c5c4e943a8..cad4aeba84 100644 --- a/hw/xen/xen_pt_config_init.c +++ b/hw/xen/xen_pt_config_init.c @@ -2031,12 +2031,16 @@ void xen_pt_config_init(XenPCIPassthroughState *s, Error **errp) } } - /* - * By default we will trap up to 0x40 in the cfg space. - * If an intel device is pass through we need to trap 0xfc, - * therefore the size should be 0xff. - */ if (xen_pt_emu_reg_grps[i].grp_id == XEN_PCI_INTEL_OPREGION) { + if (!is_igd_vga_passthrough(&s->real_device) || + s->real_device.vendor_id != PCI_VENDOR_ID_INTEL) { + continue; + } + /* + * By default we will trap up to 0x40 in the cfg space. + * If an intel device is pass through we need to trap 0xfc, + * therefore the size should be 0xff. + */ reg_grp_offset = XEN_PCI_INTEL_OPREGION; }
Currently we are creating a register group for the Intel IGD OpRegion for every device we pass through, but the XEN_PCI_INTEL_OPREGION register group is only valid for an Intel IGD. Add a check to make sure the device is an Intel IGD and a check that the administrator has enabled gfx_passthru in the xl domain configuration. Require both checks to be true before creating the register group. Use the existing is_igd_vga_passthrough() function to check for a graphics device from any vendor and that the administrator enabled gfx_passthru in the xl domain configuration, but further require that the vendor be Intel, because only Intel IGD devices have an Intel OpRegion. These are the same checks hvmloader and libxl do to determine if the Intel OpRegion needs to be mapped into the guest's memory. Also, move the comment about trapping 0xfc for the Intel OpRegion where it belongs after applying this patch. Signed-off-by: Chuck Zmudzinski <brchuckz@aol.com> --- v2: * Move the comment to an appropriate place after applying this patch * Mention that the comment is moved in the commit message v2 addresses the comment by Anthony Perard on the original version of this patch. hw/xen/xen_pt_config_init.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-)