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[PATCH v3 05/11] x86/xen: use capabilities instead of fake cpuid values for acc

From Juergen Gross <jgross@suse.com>
Newsgroups linux.kernel
Subject [PATCH v3 05/11] x86/xen: use capabilities instead of fake cpuid values for acc
Date 2017-04-18 08:40 +0200
Message-ID <txuXT-2Q2-11@gated-at.bofh.it> (permalink)
References <txuXT-2Q2-3@gated-at.bofh.it>
Organization linux.* mail to news gateway

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When running as pv domain xen_cpuid() is being used instead of
native_cpuid(). In xen_cpuid() the acc feature (thermal monitoring)
is indicated as not being present by special casing the related
cpuid leaf.

Instead of delivering fake cpuid values clear the cpu capability bit
for acc instead.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
---
 arch/x86/xen/enlighten_pv.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 37e174d9009b..53fe97bd720f 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -294,9 +294,6 @@ static void __init xen_init_cpuid_mask(void)
 	unsigned int ax, bx, cx, dx;
 	unsigned int xsave_mask;
 
-	cpuid_leaf1_edx_mask =
-		~(1 << X86_FEATURE_ACC);   /* thermal monitoring */
-
 	if (!xen_initial_domain())
 		cpuid_leaf1_edx_mask &=
 			~((1 << X86_FEATURE_ACPI));  /* disable ACPI */
@@ -325,6 +322,7 @@ static void __init xen_init_capabilities(void)
 	setup_clear_cpu_cap(X86_FEATURE_DCA);
 	setup_clear_cpu_cap(X86_FEATURE_APERFMPERF);
 	setup_clear_cpu_cap(X86_FEATURE_MTRR);
+	setup_clear_cpu_cap(X86_FEATURE_ACC);
 }
 
 static void xen_set_debugreg(int reg, unsigned long val)
-- 
2.12.0

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[PATCH v3 05/11] x86/xen: use capabilities instead of fake cpuid values for acc Juergen Gross <jgross@suse.com> - 2017-04-18 08:40 +0200

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