Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932847AbYCFPyV (ORCPT ); Thu, 6 Mar 2008 10:54:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756247AbYCFPyO (ORCPT ); Thu, 6 Mar 2008 10:54:14 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:57758 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759504AbYCFPyN (ORCPT ); Thu, 6 Mar 2008 10:54:13 -0500 Date: Thu, 6 Mar 2008 16:52:38 +0100 From: Ingo Molnar To: pageexec@freemail.hu Cc: Mathieu Desnoyers , Srinivasa DS , Andrew Morton , linux-kernel@vger.kernel.org, ananth@in.ibm.com, Jim Keniston , srikar@linux.vnet.ibm.com, SystemTAP , Andi Kleen , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Jeremy Fitzhardinge , Arjan van de Ven Subject: Re: [PATCH] x86 - Enhance DEBUG_RODATA support - alternatives Message-ID: <20080306155238.GA24008@elte.hu> References: <20080306140105.GC28438@elte.hu> <47D014E1.30964.22A9390F@pageexec.freemail.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <47D014E1.30964.22A9390F@pageexec.freemail.hu> User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 699 Lines: 20 * pageexec@freemail.hu wrote: > > + vaddr = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL); > > + WARN_ON(!vaddr); > > + local_irq_save(flags); > > + memcpy(&vaddr[(unsigned long)addr & ~PAGE_MASK], opcode, len); > > + local_irq_restore(flags); > > you probably want a BUG_ON instead (or some graceful recovery) else > the NULL deref will trigger with IRQs off... agreed - i changed it to BUG_ON() for the time being. Ingo -- 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/