Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752926AbaAQWBP (ORCPT ); Fri, 17 Jan 2014 17:01:15 -0500 Received: from mga02.intel.com ([134.134.136.20]:15837 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751177AbaAQWBM (ORCPT ); Fri, 17 Jan 2014 17:01:12 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.95,676,1384329600"; d="scan'208";a="468499334" Date: Fri, 17 Jan 2014 15:01:10 -0700 (MST) From: Keith Busch X-X-Sender: vmware@localhost.localdom To: Bjorn Helgaas cc: Alexander Gordeev , Matthew Wilcox , "linux-kernel@vger.kernel.org" , linux-nvme@lists.infradead.org, "linux-pci@vger.kernel.org" Subject: Re: [PATCH v2 5/9] nvme: Fix invalid call to irq_set_affinity_hint() In-Reply-To: Message-ID: References: <1c441f670f33375b6c41e074baf6e84e6c7bb0c2.1389904166.git.agordeev@redhat.com> User-Agent: Alpine 2.03 (LRH 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 17 Jan 2014, Bjorn Helgaas wrote: > On Fri, Jan 17, 2014 at 9:02 AM, Alexander Gordeev wrote: >> In case MSI-X and MSI initialization failed the function >> irq_set_affinity_hint() is called with uninitialized value >> in dev->entry[0].vector. This update fixes the issue. > > dev->entry[0].vector is initialized in nvme_dev_map(), and it's used > for free_irq() above the area of your patch, so I don't think this is > actually a bug, though it might be somewhat confusing. It is confusing, but there's a reason. :) We send a single command using legacy irq to discover how many msix vectors we want. The legacy entry needs to be set some time before calling request_irq in nvme_configure_admin_queue, but also within nvme_dev_start (for power-management). I don't think there's a place to set it that won't look odd when looking at nvme_setup_io_queues. I settled on 'nvme_dev_map' was because 'nvme_dev_unmap' invalidates the entries, so this seemed to provide some amount of symmetry. >> Signed-off-by: Alexander Gordeev >> --- >> drivers/block/nvme-core.c | 12 ++++++------ >> 1 files changed, 6 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c >> index 26d03fa..e292450 100644 >> --- a/drivers/block/nvme-core.c >> +++ b/drivers/block/nvme-core.c >> @@ -1790,15 +1790,15 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) >> vecs = 32; >> for (;;) { >> result = pci_enable_msi_block(pdev, vecs); >> - if (result == 0) { >> - for (i = 0; i < vecs; i++) >> - dev->entry[i].vector = i + pdev->irq; >> - break; >> + if (result > 0) { >> + vecs = result; >> + continue; >> } else if (result < 0) { >> vecs = 1; >> - break; >> } >> - vecs = result; >> + for (i = 0; i < vecs; i++) >> + dev->entry[i].vector = i + pdev->irq; >> + break; >> } >> } -- 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/