linux-kernel - [PATCH 7/9] x86/cpu/intel: replace paravirt

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Date:	Fri, 19 Feb 2016 05:08:34 -0800
From:	"Luis R. Rodriguez" <mcgrof@...nel.org>
To:	bp@...en8.de
Cc:	x86@...nel.org, linux-kernel@...r.kernel.org, luto@...capital.net,
	boris.ostrovsky@...cle.com, rusty@...tcorp.com.au,
	david.vrabel@...rix.com, konrad.wilk@...cle.com,
	xen-devel@...ts.xensource.com,
	"Luis R. Rodriguez" <mcgrof@...nel.org>
Subject: [PATCH 7/9] x86/cpu/intel: replace paravirt_enabled() for f00f work around

Use the harware subarch instead now that they are set. If we
want to test removing this work around on Xen we can do so
separatley as another independent change, for now we just want
to remove paravirt_enabled().

Signed-off-by: Luis R. Rodriguez <mcgrof@...nel.org>
---
 arch/x86/kernel/cpu/intel.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 565648bc1a0a..26d8c496c909 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -220,7 +220,9 @@ static void intel_workarounds(struct cpuinfo_x86 *c)
 	 * The Quark is also family 5, but does not have the same bug.
 	 */
 	clear_cpu_bug(c, X86_BUG_F00F);
-	if (!paravirt_enabled() && c->x86 == 5 && c->x86_model < 9) {
+	if (boot_params.hdr.hardware_subarch != X86_SUBARCH_XEN &&
+	    boot_params.hdr.hardware_subarch != X86_SUBARCH_LGUEST &&
+	    c->x86 == 5 && c->x86_model < 9) {
 		static int f00f_workaround_enabled;
 
 		set_cpu_bug(c, X86_BUG_F00F);
-- 
2.7.0