linux-kernel - [tip:x86/boot] x86/cpu/intel: Remove not needed paravirt

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 22 Apr 2016 02:52:37 -0700
From:	"tip-bot for Luis R. Rodriguez" <tipbot@...or.com>
To:	linux-tip-commits@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, brgerst@...il.com, bp@...en8.de,
	hpa@...or.com, mcgrof@...nel.org, mingo@...nel.org,
	torvalds@...ux-foundation.org, tglx@...utronix.de,
	luto@...capital.net, dvlasenk@...hat.com, peterz@...radead.org
Subject: [tip:x86/boot] x86/cpu/intel: Remove not needed paravirt_enabled()
 use for F00F work around

Commit-ID:  fa392794ed8329379f3f637da7c3c2f078309a77
Gitweb:     http://git.kernel.org/tip/fa392794ed8329379f3f637da7c3c2f078309a77
Author:     Luis R. Rodriguez <mcgrof@...nel.org>
AuthorDate: Wed, 13 Apr 2016 17:04:40 -0700
Committer:  Ingo Molnar <mingo@...nel.org>
CommitDate: Fri, 22 Apr 2016 10:29:05 +0200

x86/cpu/intel: Remove not needed paravirt_enabled() use 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>
Cc: Borislav Petkov <bp@...en8.de>
Cc: Brian Gerst <brgerst@...il.com>
Cc: Denys Vlasenko <dvlasenk@...hat.com>
Cc: H. Peter Anvin <hpa@...or.com>
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: andrew.cooper3@...rix.com
Cc: andriy.shevchenko@...ux.intel.com
Cc: bigeasy@...utronix.de
Cc: boris.ostrovsky@...cle.com
Cc: david.vrabel@...rix.com
Cc: ffainelli@...ebox.fr
Cc: george.dunlap@...rix.com
Cc: glin@...e.com
Cc: jgross@...e.com
Cc: jlee@...e.com
Cc: josh@...htriplett.org
Cc: julien.grall@...aro.org
Cc: konrad.wilk@...cle.com
Cc: kozerkov@...allels.com
Cc: lenb@...nel.org
Cc: lguest@...ts.ozlabs.org
Cc: linux-acpi@...r.kernel.org
Cc: lv.zheng@...el.com
Cc: matt@...eblueprint.co.uk
Cc: mbizon@...ebox.fr
Cc: rjw@...ysocki.net
Cc: robert.moore@...el.com
Cc: rusty@...tcorp.com.au
Cc: tiwai@...e.de
Cc: toshi.kani@...com
Cc: xen-devel@...ts.xensource.com
Link: http://lkml.kernel.org/r/1460592286-300-11-git-send-email-mcgrof@kernel.org
Signed-off-by: Ingo Molnar <mingo@...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 1f7fdb9..016b3d9 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);