Halil Pasic 05668e1d74 s390/cio: fix virtio-ccw DMA without PV ... Commit 37db8985b2 ("s390/cio: add basic protected virtualization support") breaks virtio-ccw devices with VIRTIO_F_IOMMU_PLATFORM for non Protected Virtualization (PV) guests. The problem is that the dma_mask of the ccw device, which is used by virtio core, gets changed from 64 to 31 bit, because some of the DMA allocations do require 31 bit addressable memory. For PV the only drawback is that some of the virtio structures must end up in ZONE_DMA because we have the bounce the buffers mapped via DMA API anyway. But for non PV guests we have a problem: because of the 31 bit mask guests bigger than 2G are likely to try bouncing buffers. The swiotlb however is only initialized for PV guests, because we don't want to bounce anything for non PV guests. The first such map kills the guest. Since the DMA API won't allow us to specify for each allocation whether we need memory from ZONE_DMA (31 bit addressable) or any DMA capable memory will do, let us use coherent_dma_mask (which is used for allocations) to force allocating form ZONE_DMA while changing dma_mask to DMA_BIT_MASK(64) so that at least the streaming API will regard the whole memory DMA capable. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com> Suggested-by: Robin Murphy <robin.murphy@arm.com> Fixes: 37db8985b2 ("s390/cio: add basic protected virtualization support") Link: https://lore.kernel.org/lkml/20190930153803.7958-1-pasic@linux.ibm.com Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>		2019-10-10 10:49:46 +02:00
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block	Revert "s390/dasd: Add discard support for ESE volumes"	2019-10-01 09:53:36 -06:00
char	s390 updates for the 5.4 merge window	2019-09-17 14:04:43 -07:00
cio	s390/cio: fix virtio-ccw DMA without PV	2019-10-10 10:49:46 +02:00
crypto	s390 updates for the 5.4 merge window #2	2019-09-26 11:30:16 -07:00
net	s390/qdio: clarify size of the QIB parm area	2019-10-01 09:41:36 +02:00
scsi	SCSI fixes on 20190720	2019-07-20 10:04:58 -07:00
virtio	virtio/s390: fix race on airq_areas[]	2019-07-26 13:36:18 +02:00
Makefile	s390: remove pointless drivers-y in drivers/s390/Makefile	2019-09-16 13:21:51 +02:00