Re: [PATCH] public: xen: Define missing guest handle for int32_t

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Mon, 22 Apr 2024, Julien Grall wrote:
> Hi Stefano,
> 
> On 17/04/2024 19:49, Stefano Stabellini wrote:
> > On Wed, 17 Apr 2024, Julien Grall wrote:
> > > Hi Michal,
> > > 
> > > On 17/04/2024 13:14, Michal Orzel wrote:
> > > > Commit afab29d0882f ("public: s/int/int32_t") replaced int with int32_t
> > > > in XEN_GUEST_HANDLE() in memory.h but there is no guest handle defined
> > > > for it. This results in a build failure. Example on Arm:
> > > > 
> > > > ./include/public/arch-arm.h:205:41: error: unknown type name
> > > > ‘__guest_handle_64_int32_t’
> > > >     205 | #define __XEN_GUEST_HANDLE(name)        __guest_handle_64_ ##
> > > > name
> > > >         |                                         ^~~~~~~~~~~~~~~~~~
> > > > ./include/public/arch-arm.h:206:41: note: in expansion of macro
> > > > ‘__XEN_GUEST_HANDLE’
> > > >     206 | #define XEN_GUEST_HANDLE(name)
> > > > __XEN_GUEST_HANDLE(name)
> > > >         |                                         ^~~~~~~~~~~~~~~~~~
> > > > ./include/public/memory.h:277:5: note: in expansion of macro
> > > > ‘XEN_GUEST_HANDLE’
> > > >     277 |     XEN_GUEST_HANDLE(int32_t) errs;
> > > > 
> > > > Fix it. Also, drop guest handle definition for int given no further use.
> > > > 
> > > > Fixes: afab29d0882f ("public: s/int/int32_t")
> > > > Signed-off-by: Michal Orzel <michal.orzel@xxxxxxx>
> > 
> > Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
> > 
> > 
> > > So it turned out that I committed v1 from Stefano. I was meant to commit
> > > the
> > > patch at all, but I think I started with a dirty staging :(. Sorry for
> > > that.
> > > 
> > > I have reverted Stefano's commit for now so we can take the correct patch.
> > > 
> > > Now, from my understanding, Andrew suggested on Matrix that this solution
> > > may
> > > actually be a good way to handle GUEST_HANLDEs (they were removed in v2).
> > > Maybe this can be folded in Stefano's patch?
> > 
> > v1 together with Michal's fix is correct. Also v2 alone is correct, or
> > v2 with Michal's fix is also correct.
> 
> I am slightly confused, v2 + Michal's fix means that XEN_GUEST_HANDLE(int) is
> removed and we introduce XEN_GUEST_INT(int32_t) with no user. So wouldn't this

You are right I apologize. I looked at Michal's patch too quickly and
I thought it was just adding XEN_GUEST_INT(int32_t) without removing
anything.

In that case, if you are OK with it, please ack and commit v2 only.