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

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File 561d20a0-x86-hide-MWAITX-from-PV-domains.patch of Package xen (Revision 6cff56fdd1d4b9f485c2325b73b297b5)

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# 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
@@ -967,6 +967,7 @@ 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 0x0000000a: /* Architectural Performance Monitor Features (Intel) */
--- a/xen/include/asm-x86/cpufeature.h
+++ b/xen/include/asm-x86/cpufeature.h
@@ -135,6 +135,7 @@
 #define X86_FEATURE_TBM         (6*32+21) /* trailing bit manipulations */
 #define X86_FEATURE_TOPOEXT     (6*32+22) /* topology extensions CPUID leafs */
 #define X86_FEATURE_DBEXT       (6*32+26) /* data breakpoint extension */
+#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 (Revision 6cff56fdd1d4b9f485c2325b73b297b5)

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