linux-kernel - [tip:x86/urgent] x86/cpu: Fix duplicated X86

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Date:	Sat, 9 Jul 2016 10:54:59 -0700
From:	tip-bot for Dave Hansen <tipbot@...or.com>
To:	linux-tip-commits@...r.kernel.org
Cc:	dave.hansen@...ux.intel.com, tglx@...utronix.de, bp@...en8.de,
	luto@...capital.net, jpoimboe@...hat.com, dvlasenk@...hat.com,
	peterz@...radead.org, mingo@...nel.org, brgerst@...il.com,
	torvalds@...ux-foundation.org, linux-kernel@...r.kernel.org,
	dave@...1.net, luto@...nel.org, hpa@...or.com
Subject: [tip:x86/urgent] x86/cpu: Fix duplicated X86_BUG(9) macro

Commit-ID:  8709ed4d4b0eab04561c1ec9e6ea50fd1e3897ff
Gitweb:     http://git.kernel.org/tip/8709ed4d4b0eab04561c1ec9e6ea50fd1e3897ff
Author:     Dave Hansen <dave.hansen@...ux.intel.com>
AuthorDate: Fri, 17 Jun 2016 17:15:03 -0700
Committer:  Ingo Molnar <mingo@...nel.org>
CommitDate: Sat, 9 Jul 2016 14:06:06 +0200

x86/cpu: Fix duplicated X86_BUG(9) macro

cpufeatures.h currently defines X86_BUG(9) twice on 32-bit:

	#define X86_BUG_NULL_SEG        X86_BUG(9) /* Nulling a selector preserves the base */
	...
	#ifdef CONFIG_X86_32
	#define X86_BUG_ESPFIX          X86_BUG(9) /* "" IRET to 16-bit SS corrupts ESP/RSP high bits */
	#endif

I think what happened was that this added the X86_BUG_ESPFIX, but
in an #ifdef below most of the bugs:

	58a5aac53313 x86/entry/32: Introduce and use X86_BUG_ESPFIX instead of paravirt_enabled

Then this came along and added X86_BUG_NULL_SEG, but collided
with the earlier one that did the bug below the main block
defining all the X86_BUG()s.

	7a5d67048745 x86/cpu: Probe the behavior of nulling out a segment at boot time

Signed-off-by: Dave Hansen <dave.hansen@...ux.intel.com>
Acked-by: Andy Lutomirski <luto@...nel.org>
Cc: Andy Lutomirski <luto@...capital.net>
Cc: Borislav Petkov <bp@...en8.de>
Cc: Brian Gerst <brgerst@...il.com>
Cc: Dave Hansen <dave@...1.net>
Cc: Denys Vlasenko <dvlasenk@...hat.com>
Cc: H. Peter Anvin <hpa@...or.com>
Cc: Josh Poimboeuf <jpoimboe@...hat.com>
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: stable@...r.kernel.org
Link: http://lkml.kernel.org/r/20160618001503.CEE1B141@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@...nel.org>
---
 arch/x86/include/asm/cpufeatures.h | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 4a41348..c64b1e9 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -301,10 +301,6 @@
 #define X86_BUG_FXSAVE_LEAK	X86_BUG(6) /* FXSAVE leaks FOP/FIP/FOP */
 #define X86_BUG_CLFLUSH_MONITOR	X86_BUG(7) /* AAI65, CLFLUSH required before MONITOR */
 #define X86_BUG_SYSRET_SS_ATTRS	X86_BUG(8) /* SYSRET doesn't fix up SS attrs */
-#define X86_BUG_NULL_SEG	X86_BUG(9) /* Nulling a selector preserves the base */
-#define X86_BUG_SWAPGS_FENCE	X86_BUG(10) /* SWAPGS without input dep on GS */
-
-
 #ifdef CONFIG_X86_32
 /*
  * 64-bit kernels don't use X86_BUG_ESPFIX.  Make the define conditional
@@ -312,5 +308,7 @@
  */
 #define X86_BUG_ESPFIX		X86_BUG(9) /* "" IRET to 16-bit SS corrupts ESP/RSP high bits */
 #endif
+#define X86_BUG_NULL_SEG	X86_BUG(10) /* Nulling a selector preserves the base */
+#define X86_BUG_SWAPGS_FENCE	X86_BUG(11) /* SWAPGS without input dep on GS */
 
 #endif /* _ASM_X86_CPUFEATURES_H */