x86: fix XCR0 handling

- both VMX and SVM ignored the ECX input to XSETBV
- both SVM and VMX used the full 64-bit RAX when calculating the input
  mask to XSETBV
- faults on XSETBV did not get recovered from

Also consolidate the handling for PV and HVM into a single function,
and make the per-CPU variable "xcr0" static to xstate.c.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/xen/include/asm-x86/hvm/support.h b/xen/include/asm-x86/hvm/support.h
index f9b102f2a7..7ddc806637 100644
--- a/xen/include/asm-x86/hvm/support.h
+++ b/xen/include/asm-x86/hvm/support.h
@@ -128,7 +128,7 @@ void hvm_triple_fault(void);
 
 void hvm_rdtsc_intercept(struct cpu_user_regs *regs);
 
-int hvm_handle_xsetbv(u64 new_bv);
+int __must_check hvm_handle_xsetbv(u32 index, u64 new_bv);
 
 /* These functions all return X86EMUL return codes. */
 int hvm_set_efer(uint64_t value);