linux-kernel - [PATCH v6 10/16] x86/cpu/intel: remove not needed paravirt

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Message-Id: <1460592286-300-11-git-send-email-mcgrof@kernel.org>
Date:	Wed, 13 Apr 2016 17:04:40 -0700
From:	"Luis R. Rodriguez" <mcgrof@...nel.org>
To:	bp@...en8.de, hpa@...or.com, tglx@...utronix.de, mingo@...hat.com,
	rusty@...tcorp.com.au
Cc:	x86@...nel.org, linux-kernel@...r.kernel.org, luto@...capital.net,
	boris.ostrovsky@...cle.com, jgross@...e.com,
	david.vrabel@...rix.com, konrad.wilk@...cle.com,
	xen-devel@...ts.xensource.com, lguest@...ts.ozlabs.org,
	andriy.shevchenko@...ux.intel.com, jlee@...e.com, glin@...e.com,
	matt@...eblueprint.co.uk, andrew.cooper3@...rix.com,
	rjw@...ysocki.net, lenb@...nel.org, robert.moore@...el.com,
	lv.zheng@...el.com, toshi.kani@...com, linux-acpi@...r.kernel.org,
	kozerkov@...allels.com, josh@...htriplett.org,
	bigeasy@...utronix.de, ffainelli@...ebox.fr,
	george.dunlap@...rix.com, julien.grall@...aro.org,
	mbizon@...ebox.fr, tiwai@...e.de,
	"Luis R. Rodriguez" <mcgrof@...nel.org>
Subject: [PATCH v6 10/16] x86/cpu/intel: remove not needed paravirt_enabled() for f00f work around

The X86_BUG_F00F work around is responsible for fixing up the error
generated on attempted F00F exploitation from an OOPS to a SIGILL.
There is no reason why this code should not be allowed to run on
PV guest on a F00F-affected CPU -- it would simply never trigger.
The pv_enabled() check was there only to avoid printing the f00f
workaround, so removing the check is purely a cosmetic change.

Suggested-by: Andy Lutomirski <luto@...capital.net>
Signed-off-by: Luis R. Rodriguez <mcgrof@...nel.org>
---
 arch/x86/kernel/cpu/intel.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index f71a34944b56..66509285ffdd 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -233,7 +233,7 @@ 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 (c->x86 == 5 && c->x86_model < 9) {
 		static int f00f_workaround_enabled;
 
 		set_cpu_bug(c, X86_BUG_F00F);
-- 
2.7.2