Hi Ian, > On 7 Oct 2021, at 11:53 am, Ian Jackson <i...@xenproject.org> wrote: > > Julien Grall writes ("Re: [PATCH v5 10/11] arm/libxl: Emulated PCI device > tree node in libxl"): >> On 06/10/2021 19:40, Rahul Singh wrote: >>> diff --git a/tools/libs/light/libxl_types.idl >>> b/tools/libs/light/libxl_types.idl >>> index 3f9fff653a..78b1ddf0b8 100644 >>> --- a/tools/libs/light/libxl_types.idl >>> +++ b/tools/libs/light/libxl_types.idl >>> @@ -644,6 +644,7 @@ libxl_domain_build_info = Struct("domain_build_info",[ >>> >>> ("arch_arm", Struct(None, [("gic_version", libxl_gic_version), >>> ("vuart", libxl_vuart_type), >>> + ("vpci", libxl_defbool), >> >> I have posted some comments regarding the field in v4. To summarize, >> AFAICT, this option is meant to be only set by libxl but you still let >> the toolstack (e.g. xl, libvirt) to set it. >> >> If you still want to expose to the toolstack, then I think the option >> should be outside of arch_arm. Otherwise, this should be moved in an >> internal structure (Ian, do you have any suggestion?). > > If it should be in an internal structure, probably the libxl create > context.
As Stefano suggested in another email that we can remove the vpci option, if we reach to conclusion that we need vpci option I will move it to internal structure. > > But I'm not convinced yet. In particular, if enabling VPCI is > necessary on ARM for hotplugged PCI devices[1], then there has to be > a way for the admin to say "while this domain may not have any PCI > devices right now, I may wish to hotplug some". That's what the > "passthrough=" option is for. Yes I agree with you VPCI is necessary for hot plugged PCI device and once we implement the hotplug in future we will use the passthrough= option to enable VPCI. Regards, Rahul > > See my other mail. > > [1] I think this is all true even if PCI hotplug for ARM is not > currently implemented. > > Ian.