On Fri, Jan 08, 2021 at 04:01:52PM +0100, Jan Beulich wrote: > On 08.01.2021 15:41, Roger Pau Monne wrote: > > --- a/xen/arch/x86/hypercall.c > > +++ b/xen/arch/x86/hypercall.c > > @@ -47,7 +47,7 @@ const hypercall_args_t > > hypercall_args_table[NR_hypercalls] = > > ARGS(xen_version, 2), > > ARGS(console_io, 3), > > ARGS(physdev_op_compat, 1), > > -#ifdef CONFIG_GRANT_TABLE > > +#if defined(CONFIG_GRANT_TABLE) || defined(CONFIG_PV_SHIM) > > ARGS(grant_table_op, 3), > > #endif > > ARGS(vm_assist, 2), > > This is correct when a shim-enabled build runs as shim, but > not when it runs as normal hypervisor. Just like the hypercall > handler gets patched into the hypercall table (in > pv_shim_setup_dom()), the argument count will also want > updating there, I think.
Having the argument count set when the hypercall handler is NULL is fine, as Xen won't get into processing hypercall_args_table if the handler is NULL. While it's true that can be fixed at run time in the same way that we patch the handler it seems more cumbersome, that's why I went for this IMO simpler fix. Thanks, Roger.
