El 26/11/15 a les 15.32, Jan Beulich ha escrit: >>>> On 25.11.15 at 16:18, <roger....@citrix.com> wrote: >> --- a/xen/arch/x86/hvm/hvm.c >> +++ b/xen/arch/x86/hvm/hvm.c >> @@ -2085,16 +2091,17 @@ static int hvm_load_cpu_ctxt(struct domain *d, >> hvm_domain_context_t *h) >> seg.attr.bytes = ctxt.ldtr_arbytes; >> hvm_set_segment_register(v, x86_seg_ldtr, &seg); >> >> + v->fpu_initialised = !!(ctxt.flags & XEN_X86_FPU_INITIALISED); >> /* In case xsave-absent save file is restored on a xsave-capable host */ >> - if ( cpu_has_xsave && !xsave_enabled(v) ) >> + if ( cpu_has_xsave && !xsave_enabled(v) && v->fpu_initialised ) > > Hmm, didn't I pretty explicitly ask for this to become > > if ( !v->fpu_initialised ) > memset();
I don't think this is possible with the current code. Sadly the XSTATE stuff is kind of messy IMHO. vcpu_init_fpu calls xstate_alloc_save_area which on a XSAVE capable CPUs allocates _and_ initializes the FPU registers, while on non-XSAVE capable CPUs vcpu_init_fpu just allocates the FPU memory, but doesn't initialize the registers. So either xstate_alloc_save_area also sets v->fpu_initialised = 1 (this is the simplest solution), or xstate_alloc_save_area is reworked so it only allocates the XSAVE area, but doesn't initialize it. Then XSAVE area initialization should be done in vcpu_restore_fpu_lazy. Roger. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
