Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752713AbbDCM1c (ORCPT ); Fri, 3 Apr 2015 08:27:32 -0400 Received: from mail.skyhub.de ([78.46.96.112]:58281 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751668AbbDCM1b (ORCPT ); Fri, 3 Apr 2015 08:27:31 -0400 Date: Fri, 3 Apr 2015 14:25:28 +0200 From: Borislav Petkov To: Denys Vlasenko Cc: Ingo Molnar , LKML , Andy Lutomirski , Alexei Starovoitov , Frederic Weisbecker , "H. Peter Anvin" , Kees Cook , Linus Torvalds , Oleg Nesterov , Steven Rostedt , Will Drewry Subject: [PATCH] x86/asm/entry/64: Use a define for an invalid segment Message-ID: <20150403122528.GC3418@pd.tnic> References: <1428054130-25847-1-git-send-email-bp@alien8.de> <20150403112027.GA3418@pd.tnic> <551E7EE0.5010901@redhat.com> <20150403120516.GB3418@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20150403120516.GB3418@pd.tnic> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1729 Lines: 57 On Fri, Apr 03, 2015 at 02:05:17PM +0200, Borislav Petkov wrote: > Let me do a patch. --- From: Borislav Petkov Date: Fri, 3 Apr 2015 14:22:00 +0200 Subject: [PATCH] x86/asm/entry/64: Use a define for an invalid segment selector ... instead of a naked number, for better readability. Signed-off-by: Borislav Petkov --- arch/x86/include/asm/segment.h | 2 ++ arch/x86/kernel/cpu/common.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h index d394899e055c..5a9856eb12ba 100644 --- a/arch/x86/include/asm/segment.h +++ b/arch/x86/include/asm/segment.h @@ -39,6 +39,8 @@ /* ... GDT has it cleared */ #define SEGMENT_GDT 0x0 +#define GDT_ENTRY_INVALID_SEG 0 + #ifdef CONFIG_X86_32 /* * The layout of the per-CPU GDT under Linux: diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 2c249b57e4b5..a62cf04dac8a 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1223,7 +1223,7 @@ void syscall_init(void) wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)ia32_sysenter_target); #else wrmsrl(MSR_CSTAR, ignore_sysret); - wrmsrl_safe(MSR_IA32_SYSENTER_CS, 0ULL); + wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)GDT_ENTRY_INVALID_SEG); wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL); wrmsrl_safe(MSR_IA32_SYSENTER_EIP, 0ULL); #endif -- 2.3.3 -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/