Re: [PATCH] x86/hypercall: fix gnttab hypercall args conditional build on pvshim

[Jan Beulich <jbeulich@xxxxxxxx>]

On 08.01.2021 16:42, Roger Pau Monne wrote:
> A pvshim build doesn't require the grant table functionality built in,
> but it does require knowing the number of arguments the hypercall has
> so the hypercall parameter clobbering works properly.
> 
> Instead of also setting the argument count for the gnttab case if PV
> shim functionality is enabled, just drop all of the conditionals from
> hypercall_args_table, as a hypercall having a NULL handler won't get
> to use that information anyway.
> 
> Note this hasn't been detected by osstest because the tools pvshim
> build is done without debug enabled, so the hypercall parameter
> clobbering doesn't happen.
> 
> Fixes: d2151152dd2 ('xen: make grant table support configurable')
> Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>

Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>