From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f198.google.com (mail-pf0-f198.google.com [209.85.192.198]) by kanga.kvack.org (Postfix) with ESMTP id C77146B0253 for ; Thu, 30 Jun 2016 20:12:12 -0400 (EDT) Received: by mail-pf0-f198.google.com with SMTP id e189so203833137pfa.2 for ; Thu, 30 Jun 2016 17:12:12 -0700 (PDT) Received: from mga11.intel.com (mga11.intel.com. [192.55.52.93]) by mx.google.com with ESMTP id p7si967228pfp.244.2016.06.30.17.12.11 for ; Thu, 30 Jun 2016 17:12:11 -0700 (PDT) Subject: [PATCH 1/6] x86: fix duplicated X86_BUG(9) macro From: Dave Hansen Date: Thu, 30 Jun 2016 17:12:10 -0700 References: <20160701001209.7DA24D1C@viggo.jf.intel.com> In-Reply-To: <20160701001209.7DA24D1C@viggo.jf.intel.com> Message-Id: <20160701001210.AA77B917@viggo.jf.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, linux-mm@kvack.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, bp@alien8.de, ak@linux.intel.com, mhocko@suse.com, Dave Hansen , dave.hansen@linux.intel.com, luto@kernel.org, stable@vger.kernel.org From: Dave Hansen epufeatures.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: [58a5aac5] 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. [7a5d6704] x86/cpu: Probe the behavior of nulling out a segment at boot time Signed-off-by: Dave Hansen Acked-by: Andy Lutomirski Cc: stable@vger.kernel.org --- b/arch/x86/include/asm/cpufeatures.h | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff -puN arch/x86/include/asm/cpufeatures.h~knl-leak-10-fix-x86-bugs-macros arch/x86/include/asm/cpufeatures.h --- a/arch/x86/include/asm/cpufeatures.h~knl-leak-10-fix-x86-bugs-macros 2016-06-30 17:10:41.215185869 -0700 +++ b/arch/x86/include/asm/cpufeatures.h 2016-06-30 17:10:41.218186005 -0700 @@ -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 */ _ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org