Re: [Xen-devel] [PATCH 3/6] xen/domctl: Consolidate hypercall continuation handling at the top level

[Jan Beulich <jbeulich@xxxxxxxx>]

On 05.12.2019 23:30, Andrew Cooper wrote:
> --- a/xen/arch/x86/domctl.c
> +++ b/xen/arch/x86/domctl.c
> @@ -326,9 +326,12 @@ long arch_do_domctl(
>  
>      switch ( domctl->cmd )
>      {
> -
>      case XEN_DOMCTL_shadow_op:
>          ret = paging_domctl(d, &domctl->u.shadow_op, u_domctl, 0);
> +        /*
> +         * Continuations from paging_domctl() switch index to arch_1, and
> +         * can't use the common domctl continuation path.
> +         */
>          if ( ret == -ERESTART )
>              return hypercall_create_continuation(__HYPERVISOR_arch_1,
>                                                   "h", u_domctl);

There's also XEN_DOMCTL_getpageframeinfo3 down from here which
now invokes a continuation.

> @@ -1080,6 +1068,9 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) 
> u_domctl)
>      if ( copyback && __copy_to_guest(u_domctl, op, 1) )
>          ret = -EFAULT;
>  
> +    if ( ret == -ERESTART )
> +        ret = hypercall_create_continuation(__HYPERVISOR_domctl,
> +                                            "h", u_domctl);

You may want to mention in the description the bug you fix here:
Previously the -EFAULT returning visible in context should have
canceled any active continuation.

Jan

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel