File 561d20a0-x86-hide-MWAITX-from-PV-domains.patch of Package xen.1589

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File 561d20a0-x86-hide-MWAITX-from-PV-domains.patch of Package xen.1589

# Commit 941cd44324db7eddc46cba4596fa13d505066ccf
# Date 2015-10-13 17:17:52 +0200
# Author Jan Beulich <jbeulich@suse.com>
# Committer Jan Beulich <jbeulich@suse.com>
x86: hide MWAITX from PV domains

Since MWAIT is hidden too. (Linux starting with 4.3 is making use of
that feature, and is checking for it without looking at the MWAIT one.)

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

--- a/xen/arch/x86/traps.c
+++ b/xen/arch/x86/traps.c
@@ -873,6 +873,7 @@ void pv_cpuid(struct cpu_user_regs *regs
         __clear_bit(X86_FEATURE_LWP % 32, &c);
         __clear_bit(X86_FEATURE_NODEID_MSR % 32, &c);
         __clear_bit(X86_FEATURE_TOPOEXT % 32, &c);
+        __clear_bit(X86_FEATURE_MWAITX % 32, &c);
         break;
 
     case 0x00000005: /* MONITOR/MWAIT */
--- a/xen/include/asm-x86/cpufeature.h
+++ b/xen/include/asm-x86/cpufeature.h
@@ -137,6 +137,7 @@
 #define X86_FEATURE_NODEID_MSR  (6*32+19) /* NodeId MSR */
 #define X86_FEATURE_TBM         (6*32+21) /* trailing bit manipulations */
 #define X86_FEATURE_TOPOEXT     (6*32+22) /* topology extensions CPUID leafs */
+#define X86_FEATURE_MWAITX      (6*32+29) /* MWAIT extension (MONITORX/MWAITX) */
 
 /* Intel-defined CPU features, CPUID level 0x00000007:0 (ebx), word 7 */
 #define X86_FEATURE_FSGSBASE	(7*32+ 0) /* {RD,WR}{FS,GS}BASE instructions */

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File 561d20a0-x86-hide-MWAITX-from-PV-domains.patch of Package xen.1589

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