From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CA656C433FF for ; Thu, 1 Aug 2019 10:57:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A446F206A2 for ; Thu, 1 Aug 2019 10:57:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731282AbfHAK5W (ORCPT ); Thu, 1 Aug 2019 06:57:22 -0400 Received: from 11.mo6.mail-out.ovh.net ([188.165.38.119]:54651 "EHLO 11.mo6.mail-out.ovh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726783AbfHAK5V (ORCPT ); Thu, 1 Aug 2019 06:57:21 -0400 X-Greylist: delayed 3599 seconds by postgrey-1.27 at vger.kernel.org; Thu, 01 Aug 2019 06:57:21 EDT Received: from player778.ha.ovh.net (unknown [10.108.35.95]) by mo6.mail-out.ovh.net (Postfix) with ESMTP id 0CCC21D1F9D for ; Thu, 1 Aug 2019 11:41:43 +0200 (CEST) Received: from kaod.org (lns-bzn-46-82-253-208-248.adsl.proxad.net [82.253.208.248]) (Authenticated sender: groug@kaod.org) by player778.ha.ovh.net (Postfix) with ESMTPSA id 5D8AE873BBDD; Thu, 1 Aug 2019 09:41:33 +0000 (UTC) Date: Thu, 1 Aug 2019 11:41:32 +0200 From: Greg Kurz To: Christophe JAILLET Cc: benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, allison@lohutok.net, tglx@linutronix.de, clg@kaod.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: Re: [PATCH 2/2] powerpc/xive: Add a check for memory allocation failure Message-ID: <20190801114132.4c1db5be@bahia.lan> In-Reply-To: References: X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Ovh-Tracer-Id: 12958826454390118683 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeduvddrleejgddujecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfqggfjpdevjffgvefmvefgnecuuegrihhlohhuthemucehtddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 1 Aug 2019 10:32:42 +0200 Christophe JAILLET wrote: > The result of this kzalloc is not checked. Add a check and corresponding > error handling code. > > Signed-off-by: Christophe JAILLET > --- Reviewed-by: Greg Kurz > Note that 'xive_irq_bitmap_add()' failures are not handled in > 'xive_spapr_init()' > I guess that it is not really an issue. This function is _init, so if a > memory allocation occures here, it is likely that the system will > already be in bad shape. Hmm not sure... The allocation could also fail if the "ibm,xive-lisn-ranges" property contains an insanely big range, eg. count == 1 << 31. The system isn't necessarily in bad shape in this case, but XIVE is definitely unusable and we should let a chance to the kernel to switch to XICS in this case. I guess it is worth adding proper error handling in xive_spapr_init() as well. > Anyway, the check added here would at least keep the data linked in > 'xive_irq_bitmaps' usable. > --- > arch/powerpc/sysdev/xive/spapr.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/arch/powerpc/sysdev/xive/spapr.c b/arch/powerpc/sysdev/xive/spapr.c > index b4f5eb9e0f82..52198131c75e 100644 > --- a/arch/powerpc/sysdev/xive/spapr.c > +++ b/arch/powerpc/sysdev/xive/spapr.c > @@ -53,6 +53,10 @@ static int xive_irq_bitmap_add(int base, int count) > xibm->base = base; > xibm->count = count; > xibm->bitmap = kzalloc(xibm->count, GFP_KERNEL); > + if (!xibm->bitmap) { > + kfree(xibm); > + return -ENOMEM; > + } > list_add(&xibm->list, &xive_irq_bitmaps); > > pr_info("Using IRQ range [%x-%x]", xibm->base,