From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [PATCH v2] device-assignment: register a reset function Date: Tue, 16 Nov 2010 15:49:42 +0100 Message-ID: <4CE29A06.5050509@siemens.com> References: <1289916329-6515-1-git-send-email-bernhard.kohl@nsn.com> <1289918267.2805.248.camel@x201> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Bernhard Kohl , kvm@vger.kernel.org, Thomas Ostler To: Alex Williamson Return-path: Received: from david.siemens.de ([192.35.17.14]:17096 "EHLO david.siemens.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755918Ab0KPOt5 (ORCPT ); Tue, 16 Nov 2010 09:49:57 -0500 In-Reply-To: <1289918267.2805.248.camel@x201> Sender: kvm-owner@vger.kernel.org List-ID: Am 16.11.2010 15:37, Alex Williamson wrote: > On Tue, 2010-11-16 at 15:05 +0100, Bernhard Kohl wrote: >> This is necessary because during reboot of a VM the assigned devices >> continue DMA transfers which causes memory corruption. >> >> Signed-off-by: Thomas Ostler >> Signed-off-by: Bernhard Kohl >> --- >> Changes v1 -> v2: >> - use defined macros, e.g. PCI_COMMAND >> - write all zero to the command register to disconnect the device logically >> --- >> hw/device-assignment.c | 12 ++++++++++++ >> 1 files changed, 12 insertions(+), 0 deletions(-) > > Looks good to me. > > Acked-by: Alex Williamson Acked-by: Jan Kiszka > >> diff --git a/hw/device-assignment.c b/hw/device-assignment.c >> index 5f5bde1..8d5a609 100644 >> --- a/hw/device-assignment.c >> +++ b/hw/device-assignment.c >> @@ -1434,6 +1434,17 @@ static void assigned_dev_unregister_msix_mmio(AssignedDevice *dev) >> dev->msix_table_page = NULL; >> } >> >> +static void reset_assigned_device(DeviceState *dev) >> +{ >> + PCIDevice *d = DO_UPCAST(PCIDevice, qdev, dev); >> + >> + /* >> + * When a 0 is written to the command register, the device is logically >> + * disconnected from the PCI bus. This avoids further DMA transfers. >> + */ >> + assigned_dev_pci_write_config(d, PCI_COMMAND, 0, 2); >> +} >> + >> static int assigned_initfn(struct PCIDevice *pci_dev) >> { >> AssignedDevice *dev = DO_UPCAST(AssignedDevice, dev, pci_dev); >> @@ -1544,6 +1555,7 @@ static PCIDeviceInfo assign_info = { >> .qdev.name = "pci-assign", >> .qdev.desc = "pass through host pci devices to the guest", >> .qdev.size = sizeof(AssignedDevice), >> + .qdev.reset = reset_assigned_device, >> .init = assigned_initfn, >> .exit = assigned_exitfn, >> .config_read = assigned_dev_pci_read_config, -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux