Re: [PATCH] x86/pvh: pass module command line to dom0

[Ian Jackson <iwj@xxxxxxxxxxxxxx>]

Roger Pau Monné writes ("Re: [PATCH] x86/pvh: pass module command line to 
dom0"):
> On Fri, Jan 29, 2021 at 10:26:31AM +0100, Jan Beulich wrote:
> > On 29.01.2021 10:05, Roger Pau Monne wrote:
> > > Both the multiboot and the HVM start info structures allow passing a
> > > string together with a module. Implement the missing support in
> > > pvh_load_kernel so that module strings found in the multiboot
> > > structure are forwarded to dom0.
> > > 
> > > Fixes: 62ba982424 ('x86: parse Dom0 kernel for PVHv2')
> > 
> > This really is relevant only when it's not an initrd which gets
> > passed as module, I suppose? I'm not fully convinced I'd call
> > this a bug then, but perhaps more a missing feature. Which in
> > turn means I'm not sure about the change's disposition wrt 4.15.
> > Cc-ing Ian.
> 
> Right, the whole kernel loading stuff is IMO not the best one, because
> all the multiboot modules apart from Xen and the dom0 kernel (the
> first 2) should be passed to the dom0 IMO using the HVM start_info
> structure.
> 
> The module command line is just a red herring, as none of the OSes
> that currently have PVH dom0 support need this, but still would be
> nice to get it fixed so that if new OSes are added it works properly.
> It's unexpected that a loader can append a string to a module, but
> then the dom0 kernel finds none in the start_info module list.
> 
> Regarding 4.15 acceptance: I think this is very low risk, as it
> exclusively touches PVH dom0 code which is experimental anyway, but
> I'm not going to insist on it getting committed.

Thanks for the explanation.  I'm not sure from reading this, whether
this is a bugfix, but your analysis is convincing, so:

Release-Acked-by: Ian Jackson <ian.jackson@xxxxxxxxxxxxx>