similar to: [RFC PATCH 1/2] virtio/s390: avoid race on vcdev->config

On Wed, 12 Sep 2018 16:02:01 +0200 Halil Pasic <pasic at linux.ibm.com> wrote: > Currently we have a race on vcdev->config in virtio_ccw_get_config() and > in virtio_ccw_set_config(). > > This normally does not cause problems, as these are usually infrequent > operations. But occasionally sysfs attributes are directly dependent on > pieces of virio config and trigger a

From: Halil Pasic <pasic at linux.ibm.com> Before virtio-ccw could get away with not using DMA API for the pieces of memory it does ccw I/O with. With protected virtualization this has to change, since the hypervisor needs to read and sometimes also write these pieces of memory. The hypervisor is supposed to poke the classic notifiers, if these are used, out of band with regards to ccw

From: Halil Pasic <pasic at linux.ibm.com> Before virtio-ccw could get away with not using DMA API for the pieces of memory it does ccw I/O with. With protected virtualization this has to change, since the hypervisor needs to read and sometimes also write these pieces of memory. The hypervisor is supposed to poke the classic notifiers, if these are used, out of band with regards to ccw

Before virtio-ccw could get away with not using DMA API for the pieces of memory it does ccw I/O with. With protected virtualization this has to change, since the hypervisor needs to read and sometimes also write these pieces of memory. The hypervisor is supposed to poke the classic notifiers, if these are used, out of band with regards to ccw I/O. So these need to be allocated as DMA memory

Before virtio-ccw could get away with not using DMA API for the pieces of memory it does ccw I/O with. With protected virtualization this has to change, since the hypervisor needs to read and sometimes also write these pieces of memory. The hypervisor is supposed to poke the classic notifiers, if these are used, out of band with regards to ccw I/O. So these need to be allocated as DMA memory

Before virtio-ccw could get away with not using DMA API for the pieces of memory it does ccw I/O with. With protected virtualization this has to change, since the hypervisor needs to read and sometimes also write these pieces of memory. The hypervisor is supposed to poke the classic notifiers, if these are used, out of band with regards to ccw I/O. So these need to be allocated as DMA memory

From: Alexander Gordeev <agordeev at linux.ibm.com> [ Upstream commit 5fc5b94a273655128159186c87662105db8afeb5 ] This does not fix a real bug, since virtual addresses are currently indentical to physical ones. Reviewed-by: Nico Boehr <nrb at linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev at linux.ibm.com> Signed-off-by: Janosch Frank <frankja at linux.ibm.com>

From: Alexander Gordeev <agordeev at linux.ibm.com> [ Upstream commit 5fc5b94a273655128159186c87662105db8afeb5 ] This does not fix a real bug, since virtual addresses are currently indentical to physical ones. Reviewed-by: Nico Boehr <nrb at linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev at linux.ibm.com> Signed-off-by: Janosch Frank <frankja at linux.ibm.com>

The following changes since commit 8c0f9f5b309d627182d5da72a69246f58bde1026: Revert "uapi/linux/keyctl.h: don't use C++ reserved keyword as a struct member name" (2018-09-25 13:28:58 +0200) are available in the Git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git tags/virtio-ccw-20180926 for you to fetch changes up to

On Wed, 12 Sep 2018 16:02:02 +0200 Halil Pasic <pasic at linux.ibm.com> wrote: > While ccw_io_helper() seems like intended to be exclusive in a sense that > it is supposed to facilitate I/O for at most one thread at any given > time, there is actually nothing ensuring that threads won't pile up at > vcdev->wait_q. If they all threads get woken up and see the status that

On Fri, 5 Apr 2019 01:16:12 +0200 Halil Pasic <pasic at linux.ibm.com> wrote: > Currently we have a problem if a virtio-ccw device has > VIRTIO_F_IOMMU_PLATFORM. Can you please describe what the actual problem is? > In future we do want to support DMA API with > virtio-ccw. > > Let us do the plumbing, so the feature VIRTIO_F_IOMMU_PLATFORM works > with virtio-ccw.

Currently virtio-ccw devices do not work if the device has VIRTIO_F_IOMMU_PLATFORM. In future we do want to support DMA API with virtio-ccw. Let us do the plumbing, so the feature VIRTIO_F_IOMMU_PLATFORM works with virtio-ccw. Let us also switch from legacy avail/used accessors to the DMA aware ones (even if it isn't strictly necessary), and remove the legacy accessors (we were the last

On 26/04/2019 20:32, Halil Pasic wrote: > Before virtio-ccw could get away with not using DMA API for the pieces of > memory it does ccw I/O with. With protected virtualization this has to > change, since the hypervisor needs to read and sometimes also write these > pieces of memory. > > The hypervisor is supposed to poke the classic notifiers, if these are > used, out of

On 26/04/2019 20:32, Halil Pasic wrote: > Before virtio-ccw could get away with not using DMA API for the pieces of > memory it does ccw I/O with. With protected virtualization this has to > change, since the hypervisor needs to read and sometimes also write these > pieces of memory. > > The hypervisor is supposed to poke the classic notifiers, if these are > used, out of

On Mon, 13 May 2019 11:41:36 +0200 Cornelia Huck <cohuck at redhat.com> wrote: > On Fri, 26 Apr 2019 20:32:41 +0200 > Halil Pasic <pasic at linux.ibm.com> wrote: > > > As virtio-ccw devices are channel devices, we need to use the dma area > > for any communication with the hypervisor. > > > > This patch addresses the most basic stuff (mostly what is

On 5/13/19 5:41 AM, Cornelia Huck wrote: > On Fri, 26 Apr 2019 20:32:41 +0200 > Halil Pasic <pasic at linux.ibm.com> wrote: > >> As virtio-ccw devices are channel devices, we need to use the dma area >> for any communication with the hypervisor. >> >> This patch addresses the most basic stuff (mostly what is required for >> virtio-ccw), and does take

On Tue, 14 May 2019 10:47:34 -0400 "Jason J. Herne" <jjherne at linux.ibm.com> wrote: > On 5/13/19 5:41 AM, Cornelia Huck wrote: > > On Fri, 26 Apr 2019 20:32:41 +0200 > > Halil Pasic <pasic at linux.ibm.com> wrote: > > > >> As virtio-ccw devices are channel devices, we need to use the dma area > >> for any communication with the

On Wed, 15 May 2019 22:51:58 +0200 Halil Pasic <pasic at linux.ibm.com> wrote: > On Mon, 13 May 2019 11:41:36 +0200 > Cornelia Huck <cohuck at redhat.com> wrote: > > > On Fri, 26 Apr 2019 20:32:41 +0200 > > Halil Pasic <pasic at linux.ibm.com> wrote: > > > > > As virtio-ccw devices are channel devices, we need to use the dma area > >

On Wed, 15 May 2019 22:51:58 +0200 Halil Pasic <pasic at linux.ibm.com> wrote: > On Mon, 13 May 2019 11:41:36 +0200 > Cornelia Huck <cohuck at redhat.com> wrote: > > > On Fri, 26 Apr 2019 20:32:41 +0200 > > Halil Pasic <pasic at linux.ibm.com> wrote: > > > > > As virtio-ccw devices are channel devices, we need to use the dma area > >

Thomas Huth <thuth at linux.vnet.ibm.com> writes: > Hi all, > > with the recent kernel 3.19, I get a kernel warning when I start my > KVM guest on s390 with virtio balloon enabled: The deeper problem is that virtio_ccw_get_config just silently fails on OOM. Neither get_config nor set_config are expected to fail. Cornelia, I think ccw and config_area should be allocated inside