Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757453Ab3CNOtn (ORCPT ); Thu, 14 Mar 2013 10:49:43 -0400 Received: from mail-la0-f45.google.com ([209.85.215.45]:45513 "EHLO mail-la0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756635Ab3CNOtl (ORCPT ); Thu, 14 Mar 2013 10:49:41 -0400 Subject: [PATCH bugfix 3.9] PCI: Don't try to disable Bus Master on disconnected PCI devices To: linux-kernel@vger.kernel.org From: Konstantin Khlebnikov Cc: "Rafael J. Wysocki" , kexec@lists.infradead.org, "Eric W. Biederman" , Bjorn Helgaas , Jeff Garzik , Vivek Goyal Date: Thu, 14 Mar 2013 18:49:37 +0400 Message-ID: <20130314144936.10073.2403.stgit@zurg> User-Agent: StGit/0.15 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1555 Lines: 41 This is fix for commit 7897e6022761ace7377f0f784fca059da55f5d71 from v3.9-rc1 ("PCI: Disable Bus Master unconditionally in pci_device_shutdown()") in turn that was fix for b566a22c23327f18ce941ffad0ca907e50a53d41 from v3.5-rc1 ("PCI: disable Bus Master on PCI device shutdown") Unfortunately fixing one bug uncovers another: ->shutdown() callback might switch device to deep sleep state. PCI config space no longer available after that. Link: https://lkml.org/lkml/2013/3/12/529 Signed-off-by: Konstantin Khlebnikov Reported-and-Tested-by: Vivek Goyal Cc: Bjorn Helgaas Cc: Rafael J. Wysocki --- drivers/pci/pci-driver.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index 1fa1e48..79277fb 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -390,9 +390,10 @@ static void pci_device_shutdown(struct device *dev) /* * Turn off Bus Master bit on the device to tell it to not - * continue to do DMA + * continue to do DMA. Don't touch devices in D3cold or unknown states. */ - pci_clear_master(pci_dev); + if (pci_dev->current_state <= PCI_D3hot) + pci_clear_master(pci_dev); } #ifdef CONFIG_PM -- 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/