From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765221AbZEAUJs (ORCPT ); Fri, 1 May 2009 16:09:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757279AbZEAUJk (ORCPT ); Fri, 1 May 2009 16:09:40 -0400 Received: from fg-out-1718.google.com ([72.14.220.157]:6724 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753691AbZEAUJi (ORCPT ); Fri, 1 May 2009 16:09:38 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=JJVRr8WS5aJnzZvDs6pQQv1WfP2Xx03EXHZRQWOR+y99UnbJsJIJbn1wlt6YU/rGpm GdFwtD0wwqQmKOYgKtT8/ywbkTFPBbZyJbP7nICwfQ2gX1P4734PcGdPMCtd2YfaNa5H v+nvuavHvnWevwM9DW5Vmb1NBVBrinIupbRgo= Date: Sat, 2 May 2009 00:09:37 +0400 From: Cyrill Gorcunov To: Ingo Molnar Cc: "H. Peter Anvin" , Thomas Gleixner , LKML , Jack Steiner Subject: Re: [PATCH -tip] x86: uv - prevent NULL dereference in uv_system_init Message-ID: <20090501200937.GD4633@lenovo> References: <20090501195638.GC4633@lenovo> <20090501200331.GA2645@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090501200331.GA2645@elte.hu> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [Ingo Molnar - Fri, May 01, 2009 at 10:03:31PM +0200] | | * Cyrill Gorcunov wrote: | | > We may reach NULL dereference oops if kmalloc failed. | > Lets do panic better with sensible message. | > | > Signed-off-by: Cyrill Gorcunov | > --- | > | > Actually there is a dubious place as well at early_get_nodeid. | > Is there a guarantee that we _never_ fail in early_ioremap? | > | > arch/x86/kernel/apic/x2apic_uv_x.c | 9 +++++++++ | > 1 file changed, 9 insertions(+) | > | > Index: linux-2.6.git/arch/x86/kernel/apic/x2apic_uv_x.c | > ===================================================================== | > --- linux-2.6.git.orig/arch/x86/kernel/apic/x2apic_uv_x.c | > +++ linux-2.6.git/arch/x86/kernel/apic/x2apic_uv_x.c | > @@ -584,15 +584,21 @@ void __init uv_system_init(void) | > | > bytes = sizeof(struct uv_blade_info) * uv_num_possible_blades(); | > uv_blade_info = kmalloc(bytes, GFP_KERNEL); | > + if (!uv_blade_info) | > + goto err_nomem; | | hm, i think a BUG_ON() might be shorter and more appropriate here. | We really shouldnt be running out of memory during system init. | | Ingo | Yeah, indeed! I was thinking of __GPF_NOFAIL here as well with message on top like pr_debug("UV: allocating memory\n") or something like that. It would make it even cleaner I guess. Hmm? -- Cyrill