From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.codeaurora.org ([198.145.29.96]:52810 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750994AbdI3Nbj (ORCPT ); Sat, 30 Sep 2017 09:31:39 -0400 Subject: Re: [PATCH V2] PCI: AER: fix deadlock in do_recovery To: Govindarajulu Varadarajan , benve@cisco.com, bhelgaas@google.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, jlbec@evilplan.org, hch@lst.de, mingo@redhat.com, peterz@infradead.org References: <20170930054938.43271-1-gvaradar@cisco.com> From: Sinan Kaya Message-ID: Date: Sat, 30 Sep 2017 09:31:35 -0400 MIME-Version: 1.0 In-Reply-To: <20170930054938.43271-1-gvaradar@cisco.com> Content-Type: text/plain; charset=utf-8 Sender: linux-pci-owner@vger.kernel.org List-ID: On 9/30/2017 1:49 AM, Govindarajulu Varadarajan wrote: > This patch does a pci_bus_walk and adds all the devices to a list. After > unlocking (up_read) &pci_bus_sem, we go through the list and call > err_handler of the devices with devic_lock() held. This way, we dont try > to hold both locks at same time. I do like this approach with some more feedback. I need a little bit of help here from someone that knows get/put device calls. I understand get_device() and put_device() are there to increment/decrement reference counters. This patch seems to use them as an alternative for device_lock() and device_unlock() API. If this is a good assumption, then you can get away with just replacing device_lock() with get_device() and device_unlock() with put_device() in the existing code as well. Then, you don't need to build a linklist. A nit is your history messages in the commit message belongs to a cover letter. -- Sinan Kaya Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.