Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S946449AbdDTSi4 (ORCPT ); Thu, 20 Apr 2017 14:38:56 -0400 Received: from mail-wr0-f170.google.com ([209.85.128.170]:35772 "EHLO mail-wr0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S941480AbdDTSiy (ORCPT ); Thu, 20 Apr 2017 14:38:54 -0400 MIME-Version: 1.0 In-Reply-To: <584359f9-5851-08c8-4b80-ae73abc4fe59@codeaurora.org> References: <20170419003130.5302-1-yinghai@kernel.org> <584359f9-5851-08c8-4b80-ae73abc4fe59@codeaurora.org> From: Bjorn Helgaas Date: Thu, 20 Apr 2017 13:38:32 -0500 Message-ID: Subject: Re: [PATCH v2] PCI: disable SERR for kdump kernel To: Sinan Kaya Cc: Yinghai Lu , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 978 Lines: 23 On Thu, Apr 20, 2017 at 12:14 PM, Sinan Kaya wrote: > On 4/18/2017 8:31 PM, Yinghai Lu wrote: >> * pci_setup_device - fill in class and map information of a device >> * @dev: the device structure to fill >> @@ -1572,6 +1592,9 @@ int pci_setup_device(struct pci_dev *dev >> /* device class may be changed after fixup */ >> class = dev->class >> 8; >> >> + if (is_kdump_kernel()) >> + pci_disable_serr(dev); >> + > > This sounds like something that needs to be done while shutting down > the first kernel as part of the kdump procedure rather than boot of > the kdump kernel in pci setup. In general, I would rather make the new kernel more tolerant than make assumptions about how the old kernel shut down. I don't know if there's an explicit statement of kexec philosophy on this (it'd be nice if there were), but it seems like a more robust strategy, e.g., less prone to revlock issues between the old/new kernels. Bjorn