Re: [PATCH v3 3/4] x86/pvh: Handle hypercalls for 32b PVH guests

["Jan Beulich" <JBeulich@suse.com>]

>>> On 11.07.15 at 00:20, <boris.ostrovsky@oracle.com> wrote:
> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
> ---
> Changes in v3:
> * Defined compat_mmuext_op(). (XEN_GUEST_HANDLE_PARAM(mmuext_op_compat_t)
>   is not defined in header files so I used 'void' type.

How is it not? It's in compat/xen.h (which is a generated header).

> @@ -4951,6 +4950,29 @@ static hvm_hypercall_t *const pvh_hypercall64_table[NR_hypercalls] = {
>      [ __HYPERVISOR_arch_1 ] = (hvm_hypercall_t *)paging_domctl_continuation
>  };
>  
> +extern int compat_mmuext_op(XEN_GUEST_HANDLE_PARAM(void) cmp_uops,
> +                            unsigned int count,
> +                            XEN_GUEST_HANDLE_PARAM(uint) pdone,
> +                            unsigned int foreigndom);
> +static hvm_hypercall_t *const pvh_hypercall32_table[NR_hypercalls] = {
> +    HYPERCALL(platform_op),
> +    COMPAT_CALL(memory_op),
> +    HYPERCALL(xen_version),
> +    HYPERCALL(console_io),
> +    [ __HYPERVISOR_grant_table_op ]  =
> +        (hvm_hypercall_t *)hvm_grant_table_op_compat32,
> +    COMPAT_CALL(vcpu_op),
> +    COMPAT_CALL(mmuext_op),
> +    HYPERCALL(xsm_op),
> +    COMPAT_CALL(sched_op),
> +    HYPERCALL(event_channel_op),
> +    [ __HYPERVISOR_physdev_op ] = (hvm_hypercall_t *)hvm_physdev_op_compat32,
> +    HYPERCALL(hvm_op),
> +    HYPERCALL(sysctl),
> +    HYPERCALL(domctl),
> +    [ __HYPERVISOR_arch_1 ] = (hvm_hypercall_t *)paging_domctl_continuation

Looks like you didn't fully sync with staging - did you forget that it
was you who added xenpmu_op to the 64-bit counterpart?
Without that ...

> @@ -4981,7 +5003,7 @@ int hvm_do_hypercall(struct cpu_user_regs *regs)
>          return viridian_hypercall(regs);
>  
>      if ( (eax >= NR_hypercalls) ||
> -         (is_pvh_domain(currd) ? !pvh_hypercall64_table[eax]
> +         (is_pvh_domain(currd) ? !pvh_hypercall32_table[eax]
>                                 : !hvm_hypercall32_table[eax]) )

... this will break (as we're assuming 32- and 64-bit tables to be fully
in sync here; there's still the pending work item of constructing these
tables so that this has a better chance of not getting broken).

Also, since you're touching this here anyway, could I ask you to
adjust this along the lines of the change you do further down,
i.e. to become

         !(is_pvh_domain(currd) ? pvh_hypercall32_table
                                : hvm_hypercall32_table)[eax] )

Thanks, Jan