From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:25048 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726270AbgERKGE (ORCPT ); Mon, 18 May 2020 06:06:04 -0400 Date: Mon, 18 May 2020 12:05:54 +0200 From: Cornelia Huck Subject: Re: [PATCH v4 0/8] s390x/vfio-ccw: Channel Path Handling [KVM] Message-ID: <20200518120554.6b7b04cd.cohuck@redhat.com> In-Reply-To: <20200505122745.53208-1-farman@linux.ibm.com> References: <20200505122745.53208-1-farman@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Eric Farman Cc: linux-s390@vger.kernel.org, kvm@vger.kernel.org, Halil Pasic , Jason Herne , Jared Rossi On Tue, 5 May 2020 14:27:37 +0200 Eric Farman wrote: > Here is a new pass at the channel-path handling code for vfio-ccw. > Changes from previous versions are recorded in git notes for each patch. > Patches 5 through 7 got swizzled a little bit, in order to better > compartmentalize the code they define. Basically, the IRQ definitions > were moved from patch 7 to 5, and then patch 6 was placed ahead of > patch 5. > > I have put Conny's r-b's on patches 1, 3, 4, (new) 5, and 8, and believe > I have addressed all comments from v3, with two exceptions: > > > I'm wondering if we should make this [vfio_ccw_schib_region_{write,release}] > > callback optional (not in this patch). > > I have that implemented on top of this series, and will send later as part > of a larger cleanup series. > > > One thing though that keeps coming up: do we need any kind of > > serialization? Can there be any confusion from concurrent reads from > > userspace, or are we sure that we always provide consistent data? > > I _think_ this is in good shape, though as suggested another set of > eyeballs would be nice. There is still a problem on the main > interrupt/FSM path, which I'm not attempting to address here. > > With this code plus the corresponding QEMU series (posted momentarily) > applied I am able to configure off/on a CHPID (for example, by issuing > "chchp -c 0/1 xx" on the host), and the guest is able to see both the > events and reflect the updated path masks in its structures. > > v3: https://lore.kernel.org/kvm/20200417023001.65006-1-farman@linux.ibm.com/ > v2: https://lore.kernel.org/kvm/20200206213825.11444-1-farman@linux.ibm.com/ > v1: https://lore.kernel.org/kvm/20191115025620.19593-1-farman@linux.ibm.com/ > > Eric Farman (3): > vfio-ccw: Refactor the unregister of the async regions > vfio-ccw: Refactor IRQ handlers > vfio-ccw: Add trace for CRW event > > Farhan Ali (5): > vfio-ccw: Introduce new helper functions to free/destroy regions > vfio-ccw: Register a chp_event callback for vfio-ccw > vfio-ccw: Introduce a new schib region > vfio-ccw: Introduce a new CRW region > vfio-ccw: Wire up the CRW irq and CRW region > > Documentation/s390/vfio-ccw.rst | 38 ++++++- > drivers/s390/cio/Makefile | 2 +- > drivers/s390/cio/vfio_ccw_chp.c | 148 +++++++++++++++++++++++++ > drivers/s390/cio/vfio_ccw_drv.c | 165 ++++++++++++++++++++++++++-- > drivers/s390/cio/vfio_ccw_ops.c | 65 ++++++++--- > drivers/s390/cio/vfio_ccw_private.h | 16 +++ > drivers/s390/cio/vfio_ccw_trace.c | 1 + > drivers/s390/cio/vfio_ccw_trace.h | 30 +++++ > include/uapi/linux/vfio.h | 3 + > include/uapi/linux/vfio_ccw.h | 18 +++ > 10 files changed, 458 insertions(+), 28 deletions(-) > create mode 100644 drivers/s390/cio/vfio_ccw_chp.c > Thanks, applied. The documentation needed a bit of fiddling (please double-check), and I think we want to document error codes for the schib/crw regions as well. I can do that if I find time, but I'd also happily merge a patch.