Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754537Ab1BQIxp (ORCPT ); Thu, 17 Feb 2011 03:53:45 -0500 Received: from smtp02.citrix.com ([66.165.176.63]:34523 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752123Ab1BQIxn (ORCPT ); Thu, 17 Feb 2011 03:53:43 -0500 X-IronPort-AV: E=Sophos;i="4.60,485,1291611600"; d="scan'208";a="136295808" Subject: Re: [Xen-devel] [PATCH 2/3] xen-pcifront: Sanity check the MSI/MSI-X values From: Ian Campbell To: Konrad Rzeszutek Wilk CC: "linux-kernel@vger.kernel.org" , "Konrad Rzeszutek Wilk" , Jeremy Fitzhardinge , "xen-devel@lists.xensource.com" , "Stefano Stabellini" In-Reply-To: <1297894638-28007-3-git-send-email-konrad.wilk@oracle.com> References: <1297894638-28007-1-git-send-email-konrad.wilk@oracle.com> <1297894638-28007-3-git-send-email-konrad.wilk@oracle.com> Content-Type: text/plain; charset="UTF-8" Organization: Citrix Systems, Inc. Date: Thu, 17 Feb 2011 08:53:40 +0000 Message-ID: <1297932820.16356.1317.camel@zakaz.uk.xensource.com> MIME-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2656 Lines: 81 On Wed, 2011-02-16 at 22:17 +0000, Konrad Rzeszutek Wilk wrote: > Check the returned vector values for any values that are > odd or plain incorrect (say vector value zero), and if so > print a warning. Also fixup the return values. > > Signed-off-by: Konrad Rzeszutek Wilk > --- > drivers/pci/xen-pcifront.c | 17 ++++++++++++++--- > 1 files changed, 14 insertions(+), 3 deletions(-) > > diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c > index 3a5a6fc..6acf6ae 100644 > --- a/drivers/pci/xen-pcifront.c > +++ b/drivers/pci/xen-pcifront.c > @@ -277,13 +277,20 @@ static int pci_frontend_enable_msix(struct pci_dev *dev, > if (likely(!err)) { > if (likely(!op.value)) { > /* we get the result */ > - for (i = 0; i < nvec; i++) > + for (i = 0; i < nvec; i++) { > + if (op.msix_entries[i].vector <= 0) { > + dev_warn(&dev->dev, "MSI-X entry %d" \ > + " is zero!\n", i); The test says "<= 0" but the text says "== 0". Perhaps dev_warn(&dev->dev, "MSI-X entry %d has invalid vector %d\n", i, op.msix_entries[i].vector); > > + err = -EINVAL; > + continue; Do we need / should we set *(*vector+i) to something to indicate its invalidness rather than leave it potentially uninitialised? > + } > *(*vector+i) = op.msix_entries[i].vector; BTW does the double indirection of the vector serve a purpose? Everywhere I can see just updates *(*vector+i), I can't see any realloc of the array itself etc. Removing the extra level of indirection leads to vector[i] = foo instead which is much easier on the eye. > - return 0; > + } > + return err; > } else { > printk(KERN_DEBUG "enable msix get value %x\n", > op.value); > - return op.value; > + return err; I think all of these "return err"s can now be pulled out to the end of the function? makes it clearer what the return is. > } > } else { > dev_err(&dev->dev, "enable msix get err %x\n", err); > @@ -325,6 +332,10 @@ static int pci_frontend_enable_msi(struct pci_dev *dev, int **vector) > err = do_pci_op(pdev, &op); > if (likely(!err)) { > *(*vector) = op.value; > + if (op.value <= 0) { > + dev_warn(&dev->dev, "MSI entry is zero!\n"); Same comment re <= vs == 0. > + err = -EINVAL; > + } > } else { > dev_err(&dev->dev, "pci frontend enable msi failed for dev " > "%x:%x\n", op.bus, op.devfn); -- 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/