From: Jan Beulich <jbeulich@suse.com>
Date: Thu, 22 Jan 2015 11:48:40 +0000 (+0100)
Subject: x86: correctly check for sub-leaf zero of leaf 7 in pv_cpuid()
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~3888
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/%22/%22http:/www.example.com/cgi/%22?a=commitdiff_plain;h=ae1edef1ae33f3bcff2580116ae2b7c9ffef42f2;p=xen.git

x86: correctly check for sub-leaf zero of leaf 7 in pv_cpuid()

Only the low 32 bits are relevant.

For consistency also change a cast on regs->eax to regs->_eax.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
---

diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c
index bd04dad487..a8d7bb673b 100644
--- a/xen/arch/x86/traps.c
+++ b/xen/arch/x86/traps.c
@@ -881,7 +881,7 @@ void pv_cpuid(struct cpu_user_regs *regs)
         }
     }
 
-    switch ( (uint32_t)regs->eax )
+    switch ( regs->_eax )
     {
     case 0x00000001:
         /* Modify Feature Information. */
@@ -916,7 +916,7 @@ void pv_cpuid(struct cpu_user_regs *regs)
         break;
 
     case 0x00000007:
-        if ( regs->ecx == 0 )
+        if ( regs->_ecx == 0 )
             b &= (cpufeat_mask(X86_FEATURE_BMI1) |
                   cpufeat_mask(X86_FEATURE_HLE)  |
                   cpufeat_mask(X86_FEATURE_AVX2) |