Michael S. Tsirkin 0d5415b489 Revert "vring: Force use of DMA API for ARM-based systems with legacy devices" ... This reverts commit c7070619f3. This has been shown to regress on some ARM systems: by forcing on DMA API usage for ARM systems, we have inadvertently kicked open a hornets' nest in terms of cache-coherency. Namely that unless the virtio device is explicitly described as capable of coherent DMA by firmware, the DMA APIs on ARM and other DT-based platforms will assume it is non-coherent. This turns out to cause a big problem for the likes of QEMU and kvmtool, which generate virtio-mmio devices in their guest DTs but neglect to add the often-overlooked "dma-coherent" property; as a result, we end up with the guest making non-cacheable accesses to the vring, the host doing so cacheably, both talking past each other and things going horribly wrong. We are working on a safer work-around. Fixes: c7070619f3 ("vring: Force use of DMA API for ARM-based systems with legacy devices") Reported-by: Robin Murphy <robin.murphy@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com>		2017-02-03 23:38:50 +02:00
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Kconfig	docs: fix locations of several documents that got moved	2016-10-24 08:12:35 -02:00
Makefile	Add virtio-input driver.	2015-03-29 12:13:52 +10:30
virtio.c	virtio: fix memory leak of virtio ida cache layers	2015-12-07 17:28:01 +02:00
virtio_balloon.c	virtio: update balloon size in balloon "probe"	2016-10-31 00:21:41 +02:00
virtio_input.c	virtio: make find_vqs() checkpatch.pl-friendly	2016-01-12 20:47:06 +02:00
virtio_mmio.c	virtio_mmio: Set DMA masks appropriately	2017-01-25 00:33:10 +02:00
virtio_pci_common.c	virtio_pci: split vp_try_to_find_vqs into INTx and MSI-X variants	2016-12-16 00:12:49 +02:00
virtio_pci_common.h	virtio_pci: use pci_alloc_irq_vectors	2016-12-16 00:12:47 +02:00
virtio_pci_legacy.c	virtio_pci: Limit DMA mask to 44 bits for legacy virtio devices	2016-10-31 00:21:39 +02:00
virtio_pci_modern.c	virtio_pci_modern: fix complaint by sparse	2016-12-15 06:39:46 +02:00
virtio_ring.c	Revert "vring: Force use of DMA API for ARM-based systems with legacy devices"	2017-02-03 23:38:50 +02:00