Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754059AbbFVPnc (ORCPT ); Mon, 22 Jun 2015 11:43:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38583 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753932AbbFVPnI (ORCPT ); Mon, 22 Jun 2015 11:43:08 -0400 Message-ID: <1434987786.3700.218.camel@redhat.com> Subject: Re: [PATCH v4 0/4] VFIO platform reset From: Alex Williamson To: Baptiste Reynal Cc: Eric Auger , eric.auger@st.com, "moderated list:ARM SMMU DRIVER" , open list , patches@linaro.org, Christoffer Dall , Christian Pinto , Daniel Raho Date: Mon, 22 Jun 2015 09:43:06 -0600 In-Reply-To: References: <1434359385-19916-1-git-send-email-eric.auger@linaro.org> <1434580294.5628.135.camel@redhat.com> <1434644277.3700.41.camel@redhat.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6545 Lines: 162 On Fri, 2015-06-19 at 09:53 +0200, Baptiste Reynal wrote: > [1-4/4] > Acked-by: Baptiste Reynal > Tested-by: Baptiste Reynal > Reviewed-by: Baptiste Reynal FWIW, I think that Acked-by implies Reviewed-by, so I'll drop that tag, but add the other two to the series. Eric also has this patch that needs your ack: https://lkml.org/lkml/2015/6/15/129 And I'd like one for this: https://lkml.org/lkml/2015/6/18/631 I don't want it to appear that I'm volunteering you for this job ;) Since the merge window just opened, I'd like to wrap-up the existing on-list patches and get a pull request out. Thanks, Alex > On Thu, Jun 18, 2015 at 6:17 PM, Alex Williamson > wrote: > > On Thu, 2015-06-18 at 17:23 +0200, Baptiste Reynal wrote: > >> Hello everyone, > >> > >> I tested and reviewed the patches, everything's fine for me. > > > > Hi Baptiste, > > > > Would you like to provide a Sign-off/Ack/Review tag for the series then? > > > >> I agree to be maintainer of vfio platform drivers, though I don't > >> think the volume of patches about VFIO will justify a new mailing > >> list. > > > > Ok, I'll officially post the patch for MAINTAINERS then. Until someone > > complains, we'll continue to use the kvm list. Thanks, > > > > Alex > > > >> On Thu, Jun 18, 2015 at 12:31 AM, Alex Williamson > >> wrote: > >> > On Mon, 2015-06-15 at 11:09 +0200, Eric Auger wrote: > >> >> In situations where the userspace driver is stopped abnormally and the > >> >> VFIO platform device is released, the assigned HW device currently is > >> >> left running. As a consequence the HW device might continue issuing IRQs > >> >> and performing DMA accesses. > >> >> > >> >> On release, no physical IRQ handler is setup anymore. Also the DMA buffers > >> >> are unmapped leading to IOMMU aborts. So there is no serious consequence. > >> >> > >> >> However when assigning that HW device again to another userspace driver, > >> >> this latter might face some unexpected IRQs and DMA accesses, which are > >> >> the result of the previous assignment. > >> >> > >> >> In virtualization use-case, a VM newly granted with that HW device may be > >> >> impacted by the assignment of that device to a previous VM: > >> >> - IRQs may be injected very early when booting the new guest, even before > >> >> the guest driver has initialized leading to possible driver state > >> >> inconsistency. > >> >> - DMA accesses may hit the newly mapped VM address space at addresses that > >> >> may jeopardize the integrity of the newly installed VM. > >> >> > >> >> Obviously the criticity depends on the assigned HW device. > >> >> > >> >> As opposed to PCI, there is no standard mechanism to reset the platform > >> >> device. > >> >> > >> >> This series proposes to implement device specific reset functions in > >> >> separate in-kernel vfio reset modules. The vfio-platform driver holds > >> >> a whitelist of implemented triplets (compat string, module name, > >> >> reset function name). When the vfio-platform driver is probed it identifies > >> >> the fellow reset module/function matching the compat string of the > >> >> device, if any, and forces the load of this reset module. > >> >> > >> >> A first reset module is provided: the vfio-platform-calxedaxgmac > >> >> module which implements a basic reset for the Calxeda xgmac. > >> >> > >> >> The series can be found at > >> >> https://git.linaro.org/people/eric.auger/linux.git/shortlog/refs/heads/v4.1-rc8-reset-v4 > >> >> > >> >> History: > >> >> v3 -> v4: > >> >> - fix the commit message of "VFIO: platform: add reset struct and lookup table" > >> > > >> > Baptiste, > >> > > >> > Any comments? Should we also add something like this to MAINTAINERS > >> > before we go much further? > >> > > >> > diff --git a/MAINTAINERS b/MAINTAINERS > >> > index d8afd29..c6bf7f6 100644 > >> > --- a/MAINTAINERS > >> > +++ b/MAINTAINERS > >> > @@ -10545,6 +10545,12 @@ F: drivers/vfio/ > >> > F: include/linux/vfio.h > >> > F: include/uapi/linux/vfio.h > >> > > >> > +VFIO PLATFORM DRIVER > >> > +M: Baptiste Reynal > >> > +L: kvm@vger.kernel.org > >> > +S: Maintained > >> > +F: drivers/vfio/platform/ > >> > + > >> > VIDEOBUF2 FRAMEWORK > >> > M: Pawel Osciak > >> > M: Marek Szyprowski > >> > > >> > I'm not sure what you want to be the primary list, maybe it's time to > >> > ask for a vfio list. Thanks, > >> > Alex > >> > > >> >> > >> >> v2 -> v3: > >> >> - remove void module_init/exit functions in calxeda reset module > >> >> - remove enum vfio_platform_reset_type > >> >> - for reset lookup, use ARRAY_SIZE > >> >> - in reset put use symbol_put_addr > >> >> > >> >> v1 -> v2: > >> >> - much simplified compared to v1 although principle of external modules is > >> >> kept: removed mechanism of dynamic registration of reset functions > >> >> - list is replaced by whitelist lookup table > >> >> - name of the reset function also stored in the lookup table > >> >> - autoload of reset modules > >> >> > >> >> RFC -> PATCH v1: > >> >> - solution now based on a lookup list instead of specialized driver > >> >> > >> >> > >> >> Eric Auger (4): > >> >> VFIO: platform: add reset struct and lookup table > >> >> VFIO: platform: add reset callback > >> >> VFIO: platform: populate the reset function on probe > >> >> VFIO: platform: Calxeda xgmac reset module > >> >> > >> >> drivers/vfio/platform/Kconfig | 2 + > >> >> drivers/vfio/platform/Makefile | 2 + > >> >> drivers/vfio/platform/reset/Kconfig | 7 ++ > >> >> drivers/vfio/platform/reset/Makefile | 5 ++ > >> >> .../platform/reset/vfio_platform_calxedaxgmac.c | 86 ++++++++++++++++++++++ > >> >> drivers/vfio/platform/vfio_platform_common.c | 60 ++++++++++++++- > >> >> drivers/vfio/platform/vfio_platform_private.h | 7 ++ > >> >> 7 files changed, 166 insertions(+), 3 deletions(-) > >> >> create mode 100644 drivers/vfio/platform/reset/Kconfig > >> >> create mode 100644 drivers/vfio/platform/reset/Makefile > >> >> create mode 100644 drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c > >> >> > >> > > >> > > >> > > > > > > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in Please read the FAQ at http://www.tux.org/lkml/