From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754844Ab1E2UO4 (ORCPT ); Sun, 29 May 2011 16:14:56 -0400 Received: from swampdragon.chaosbits.net ([90.184.90.115]:45313 "EHLO swampdragon.chaosbits.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752153Ab1E2UOz (ORCPT ); Sun, 29 May 2011 16:14:55 -0400 Date: Sun, 29 May 2011 22:07:06 +0200 (CEST) From: Jesper Juhl To: Andrew Lutomirski cc: Thomas Gleixner , Ingo Molnar , x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 4/5] x86-64: Replace vsyscall gettimeofday fallback with int 0xcc In-Reply-To: Message-ID: References: <452208dbdf79d4c821d701d5973621bf7546419a.1306517576.git.luto@mit.edu> User-Agent: Alpine 2.00 (LNX 1167 2008-08-23) MIME-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="8323328-932590342-1306699626=:4411" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323328-932590342-1306699626=:4411 Content-Type: TEXT/PLAIN; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT On Sun, 29 May 2011, Andrew Lutomirski wrote: > On Sun, May 29, 2011 at 3:54 PM, Jesper Juhl wrote: > > On Sun, 29 May 2011, Jesper Juhl wrote: > > > >> On Fri, 27 May 2011, Andy Lutomirski wrote: > >> > >> > Now the only way to issue a syscall with side effects through the > >> > vsyscall page is to call a misaligned instruction.  I haven't > >> > checked for that. > >> > > >> > Signed-off-by: Andy Lutomirski > >> > --- > >> >  arch/x86/include/asm/traps.h    |    4 +++ > >> >  arch/x86/include/asm/vsyscall.h |    6 +++++ > >> >  arch/x86/kernel/entry_64.S      |    2 + > >> >  arch/x86/kernel/traps.c         |    4 +++ > >> >  arch/x86/kernel/vsyscall_64.c   |   47 ++++++++++++++++++++++++++++++++++----- > >> >  5 files changed, 57 insertions(+), 6 deletions(-) > >> > > >> > >> one very tiny nit below. > >> > >> [...] > >> > diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c > >> > index b9b6716..d34894e 100644 > >> > --- a/arch/x86/kernel/traps.c > >> > +++ b/arch/x86/kernel/traps.c > >> > @@ -872,6 +872,10 @@ void __init trap_init(void) > >> >     set_bit(SYSCALL_VECTOR, used_vectors); > >> >  #endif > >> > > >> > +   set_system_intr_gate(0xCC, &intcc); > >> > +   set_bit(0xCC, used_vectors); > >> > +   printk(KERN_ERR "intcc gate isntalled\n"); > >> > >> Let's spell the error message correctly: > >> > >>       printk(KERN_ERR "intcc gate installed\n"); > >> > > Hmm, why is this KERN_ERR btw? Shouldn't it just be KERN_NOTICE or > > KERN_INFO ? > > IMO it shouldn't be there at all. It was a debugging leftover that I > forgot to delete. > Just removing it sounds good to me :) -- Jesper Juhl http://www.chaosbits.net/ Don't top-post http://www.catb.org/jargon/html/T/top-post.html Plain text mails only, please. --8323328-932590342-1306699626=:4411--