From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-la0-x22c.google.com ([2a00:1450:4010:c03::22c]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UG9TS-0001x2-H0 for kexec@lists.infradead.org; Thu, 14 Mar 2013 14:49:47 +0000 Received: by mail-la0-f44.google.com with SMTP id eb20so2578971lab.3 for ; Thu, 14 Mar 2013 07:49:40 -0700 (PDT) Subject: [PATCH bugfix 3.9] PCI: Don't try to disable Bus Master on disconnected PCI devices From: Konstantin Khlebnikov Date: Thu, 14 Mar 2013 18:49:37 +0400 Message-ID: <20130314144936.10073.2403.stgit@zurg> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: linux-kernel@vger.kernel.org Cc: "Rafael J. Wysocki" , kexec@lists.infradead.org, "Eric W. Biederman" , Bjorn Helgaas , Jeff Garzik , Vivek Goyal 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 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec