Re: [Xen-devel] [PATCH RFC v2 12/12] x86: activate per-vcpu stacks in case of xpti

2018-01-31 Thread Jan Beulich
>>> On 30.01.18 at 18:33, wrote: > On 30/01/18 17:33, Jan Beulich wrote: > On 22.01.18 at 13:32, wrote: >>> --- a/xen/arch/x86/domain.c >>> +++ b/xen/arch/x86/domain.c >>> @@ -1585,9 +1585,28 @@ static inline bool need_full_gdt(const struct domain >>> *d) >>> return is_pv_domain(d) && !

Re: [Xen-devel] [PATCH RFC v2 12/12] x86: activate per-vcpu stacks in case of xpti

2018-01-30 Thread Juergen Gross
On 30/01/18 17:33, Jan Beulich wrote: On 22.01.18 at 13:32, wrote: >> When scheduling a vcpu subject to xpti activate the per-vcpu stacks >> by loading the vcpu specific gdt and tss. When de-scheduling such a >> vcpu switch back to the per physical cpu gdt and tss. >> >> Accessing the user re

Re: [Xen-devel] [PATCH RFC v2 12/12] x86: activate per-vcpu stacks in case of xpti

2018-01-30 Thread Jan Beulich
>>> On 22.01.18 at 13:32, wrote: > When scheduling a vcpu subject to xpti activate the per-vcpu stacks > by loading the vcpu specific gdt and tss. When de-scheduling such a > vcpu switch back to the per physical cpu gdt and tss. > > Accessing the user registers on the stack is done via helpers as

[Xen-devel] [PATCH RFC v2 12/12] x86: activate per-vcpu stacks in case of xpti

2018-01-22 Thread Juergen Gross
When scheduling a vcpu subject to xpti activate the per-vcpu stacks by loading the vcpu specific gdt and tss. When de-scheduling such a vcpu switch back to the per physical cpu gdt and tss. Accessing the user registers on the stack is done via helpers as depending on XPTI active or not the registe