| Message ID | 1455821530-4263-6-git-send-email-david.vrabel@citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 18/02/16 18:52, David Vrabel wrote: > Add a parameter to allow the toolstack to set the x87 FIP width in case > the hypervisor's heuristics do the wrong thing. I think this would be better as a HVM param since: a) it only needs to be changed for HVM guests; b) it would allow the guest agent or OS (which may be able to make a better decision) to set it; and c) it can be saved/restored across a migrate. David > > Signed-off-by: David Vrabel <david.vrabel@citrix.com> > --- > xen/arch/x86/domctl.c | 10 ++++++++++ > xen/include/public/domctl.h | 1 + > 2 files changed, 11 insertions(+) > > diff --git a/xen/arch/x86/domctl.c b/xen/arch/x86/domctl.c > index 3a3ebbf..f75cd69 100644 > --- a/xen/arch/x86/domctl.c > +++ b/xen/arch/x86/domctl.c > @@ -1415,6 +1415,16 @@ int arch_domctl_param(struct domain *d, uint32_t param, bool_t set, > > switch ( param ) > { > + case XEN_DOMCTL_PARAM_ARCH_X86_FIP_WIDTH: > + *value = d->arch.x87_fip_width; > + if ( set ) > + { > + if ( new_value != 0 && new_value != 4 && new_value != 8 ) > + return -EINVAL; > + d->arch.x87_fip_width = new_value; > + } > + break; > + > default: > return -EINVAL; > } > diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h > index 330b3e7..26d4096 100644 > --- a/xen/include/public/domctl.h > +++ b/xen/include/public/domctl.h > @@ -1100,6 +1100,7 @@ DEFINE_XEN_GUEST_HANDLE(xen_domctl_psr_cat_op_t); > * > * Not all parameters are valid for all architectures or domain types. > */ > +#define XEN_DOMCTL_PARAM_ARCH_X86_FIP_WIDTH 0 > #define XEN_DOMCTL_PARAM_SET (1u << 31) > > struct xen_domctl_param { >
>>> On 19.02.16 at 11:05, <david.vrabel@citrix.com> wrote: > On 18/02/16 18:52, David Vrabel wrote: >> Add a parameter to allow the toolstack to set the x87 FIP width in case >> the hypervisor's heuristics do the wrong thing. > > I think this would be better as a HVM param since: a) it only needs to > be changed for HVM guests; b) it would allow the guest agent or OS > (which may be able to make a better decision) to set it; and c) it can > be saved/restored across a migrate. I had wondered namely about a) when seeing patch 1, and I agree with all of the points made (thus eliminating patches 1 and 2). Jan
diff --git a/xen/arch/x86/domctl.c b/xen/arch/x86/domctl.c index 3a3ebbf..f75cd69 100644 --- a/xen/arch/x86/domctl.c +++ b/xen/arch/x86/domctl.c @@ -1415,6 +1415,16 @@ int arch_domctl_param(struct domain *d, uint32_t param, bool_t set, switch ( param ) { + case XEN_DOMCTL_PARAM_ARCH_X86_FIP_WIDTH: + *value = d->arch.x87_fip_width; + if ( set ) + { + if ( new_value != 0 && new_value != 4 && new_value != 8 ) + return -EINVAL; + d->arch.x87_fip_width = new_value; + } + break; + default: return -EINVAL; } diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h index 330b3e7..26d4096 100644 --- a/xen/include/public/domctl.h +++ b/xen/include/public/domctl.h @@ -1100,6 +1100,7 @@ DEFINE_XEN_GUEST_HANDLE(xen_domctl_psr_cat_op_t); * * Not all parameters are valid for all architectures or domain types. */ +#define XEN_DOMCTL_PARAM_ARCH_X86_FIP_WIDTH 0 #define XEN_DOMCTL_PARAM_SET (1u << 31) struct xen_domctl_param {
Add a parameter to allow the toolstack to set the x87 FIP width in case the hypervisor's heuristics do the wrong thing. Signed-off-by: David Vrabel <david.vrabel@citrix.com> --- xen/arch/x86/domctl.c | 10 ++++++++++ xen/include/public/domctl.h | 1 + 2 files changed, 11 insertions(+)