From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.citrix.com ([66.165.176.89]:2375 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753718AbaGJND1 (ORCPT ); Thu, 10 Jul 2014 09:03:27 -0400 From: David Vrabel To: CC: David Vrabel , Bjorn Helgaas , , Konrad Rzeszutek Wilk , Boris Ostrovsky Subject: [PATCHv1 0/2] xen-pciback: allow device reset to work more often Date: Thu, 10 Jul 2014 14:03:12 +0100 Message-ID: <1404997394-15715-1-git-send-email-david.vrabel@citrix.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-pci-owner@vger.kernel.org List-ID: When a PCI device is passed through to a different domain, it must be reset to ensure it works correctly in the new domain. Usually the toolstack will request a device reset via the "reset" sysfs file. But this file is not present if a function reset is not available. A common use case is a GPU device and its associated audio function. In the case where these two devices are simultaneously co-assigned to the same domain, it is safe to reset them with an SBR. Patch #1 export pci_probe_reset_function() so pciback can know if an alternate reset mechanism needs to be proved. Patch #2 adds a "reset" file to devices bound to pciback that performs the SBR if it is safe to do so. David