From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753300Ab3ACMBt (ORCPT ); Thu, 3 Jan 2013 07:01:49 -0500 Received: from e7.ny.us.ibm.com ([32.97.182.137]:37972 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753191Ab3ACMBp (ORCPT ); Thu, 3 Jan 2013 07:01:45 -0500 Date: Thu, 3 Jan 2013 17:31:29 +0530 From: Srikar Dronamraju To: Oleg Nesterov Cc: Ingo Molnar , Peter Zijlstra , Ananth N Mavinakayanahalli , Anton Arapov , Frank Eigler , Josh Stone , "Suzuki K. Poulose" , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] uprobes/x86: Change __skip_sstep() to actually skip the whole insn Message-ID: <20130103120129.GF8140@linux.vnet.ibm.com> Reply-To: Srikar Dronamraju References: <20121230154657.GA28488@redhat.com> <20121230154719.GA28510@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20121230154719.GA28510@redhat.com> User-Agent: Mutt/1.5.20 (2009-06-14) X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13010312-5806-0000-0000-00001DBA4FC8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Oleg Nesterov [2012-12-30 16:47:19]: > __skip_sstep() doesn't update regs->ip. Currently this is correct > but only "by accident" and it doesn't skip the whole insn. Change > it to advance ->ip by the length of the detected 0x66*0x90 sequence. > > Signed-off-by: Oleg Nesterov Acked-by: Srikar Dronamraju > --- > arch/x86/kernel/uprobes.c | 5 ++++- > 1 files changed, 4 insertions(+), 1 deletions(-) > > diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c > index c71025b..4e33a35 100644 > --- a/arch/x86/kernel/uprobes.c > +++ b/arch/x86/kernel/uprobes.c > @@ -680,8 +680,11 @@ static bool __skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs) > if (auprobe->insn[i] == 0x66) > continue; > > - if (auprobe->insn[i] == 0x90) > + if (auprobe->insn[i] == 0x90) { > + regs->ip = uprobe_get_swbp_addr(regs); > + regs->ip += i + 1; > return true; > + } > > break; > } > -- > 1.5.5.1 >