| Message ID | a2e946dfb45260a5e29cec3b2195e4c1385b0d63.1654876622.git.brchuckz@aol.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | xen/pass-through: don't create needless register group | expand |
On Fri, Jun 10, 2022 at 12:23:35PM -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. > > Signed-off-by: Chuck Zmudzinski <brchuckz@aol.com> > --- > hw/xen/xen_pt_config_init.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/hw/xen/xen_pt_config_init.c b/hw/xen/xen_pt_config_init.c > index c5c4e943a8..ffd915654c 100644 > --- a/hw/xen/xen_pt_config_init.c > +++ b/hw/xen/xen_pt_config_init.c > @@ -2037,6 +2037,10 @@ void xen_pt_config_init(XenPCIPassthroughState *s, Error **errp) > * therefore the size should be 0xff. > */ Could you move that comment? I think it would make more sense to comment the "reg_grp_offset=XEN_PCI_INTEL_OPREGION" line now that the `if` block also skip setting up the group on non-intel devices. > 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; > + } > reg_grp_offset = XEN_PCI_INTEL_OPREGION; > } Thanks,
On 6/17/22 9:07 AM, Anthony PERARD wrote: > On Fri, Jun 10, 2022 at 12:23:35PM -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. >> >> Signed-off-by: Chuck Zmudzinski <brchuckz@aol.com> >> --- >> hw/xen/xen_pt_config_init.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/hw/xen/xen_pt_config_init.c b/hw/xen/xen_pt_config_init.c >> index c5c4e943a8..ffd915654c 100644 >> --- a/hw/xen/xen_pt_config_init.c >> +++ b/hw/xen/xen_pt_config_init.c >> @@ -2037,6 +2037,10 @@ void xen_pt_config_init(XenPCIPassthroughState *s, Error **errp) >> * therefore the size should be 0xff. >> */ > Could you move that comment? I think it would make more sense to comment > the "reg_grp_offset=XEN_PCI_INTEL_OPREGION" line now that the `if` block > also skip setting up the group on non-intel devices. OK. I just e-mailed interested parties v2 that moves the comment and mentions that the comment is moved in the commit message. Best Regards, Chuck > >> 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; >> + } >> reg_grp_offset = XEN_PCI_INTEL_OPREGION; >> } > Thanks, >
diff --git a/hw/xen/xen_pt_config_init.c b/hw/xen/xen_pt_config_init.c index c5c4e943a8..ffd915654c 100644 --- a/hw/xen/xen_pt_config_init.c +++ b/hw/xen/xen_pt_config_init.c @@ -2037,6 +2037,10 @@ void xen_pt_config_init(XenPCIPassthroughState *s, Error **errp) * 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; + } 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. Signed-off-by: Chuck Zmudzinski <brchuckz@aol.com> --- hw/xen/xen_pt_config_init.c | 4 ++++ 1 file changed, 4 insertions(+)