user/sven/linux.git/drivers/virtio, branch v4.9.99

virtio_ring: fix num_free handling in error case

2018-03-18T10:18:50Z

commit e82df670235138575b37ff0ec24412a471efd97f upstream. The vq->vq.num_free hasn't been changed when error happens, so it shouldn't be changed when handling the error. Fixes: 780bc7903a32 ("virtio_ring: Support DMA APIs") Cc: Andy Lutomirski Cc: Michael S. Tsirkin Cc: stable@vger.kernel.org Signed-off-by: Tiwei Bie Signed-off-by: Michael S. Tsirkin Signed-off-by: Greg Kroah-Hartman

virtio_balloon: prevent uninitialized variable use

2017-12-25T13:23:42Z

[ Upstream commit f0bb2d50dfcc519f06f901aac88502be6ff1df2c ] The latest gcc-7.0.1 snapshot reports a new warning: virtio/virtio_balloon.c: In function 'update_balloon_stats': virtio/virtio_balloon.c:258:26: error: 'events[2]' is used uninitialized in this function [-Werror=uninitialized] virtio/virtio_balloon.c:260:26: error: 'events[3]' is used uninitialized in this function [-Werror=uninitialized] virtio/virtio_balloon.c:261:56: error: 'events[18]' is used uninitialized in this function [-Werror=uninitialized] virtio/virtio_balloon.c:262:56: error: 'events[17]' is used uninitialized in this function [-Werror=uninitialized] This seems absolutely right, so we should add an extra check to prevent copying uninitialized stack data into the statistics. >From all I can tell, this has been broken since the statistics code was originally added in 2.6.34. Fixes: 9564e138b1f6 ("virtio: Add memory statistics reporting to the balloon driver (V4)") Signed-off-by: Arnd Bergmann Signed-off-by: Ladi Prosek Signed-off-by: Michael S. Tsirkin Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

virtio-balloon: use actual number of stats for stats queue buffers

2017-12-25T13:23:42Z

[ Upstream commit 9646b26e85896ef0256e66649f7937f774dc18a6 ] The virtio balloon driver contained a not-so-obvious invariant that update_balloon_stats has to update exactly VIRTIO_BALLOON_S_NR counters in order to send valid stats to the host. This commit fixes it by having update_balloon_stats return the actual number of counters, and its callers use it when pushing buffers to the stats virtqueue. Note that it is still out of spec to change the number of counters at run-time. "Driver MUST supply the same subset of statistics in all buffers submitted to the statsq." Suggested-by: Arnd Bergmann Signed-off-by: Ladi Prosek Signed-off-by: Michael S. Tsirkin Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

virtio: release virtio index when fail to device_register

2017-12-14T08:28:10Z

commit e60ea67bb60459b95a50a156296041a13e0e380e upstream. index can be reused by other virtio device. Signed-off-by: weiping zhang Reviewed-by: Cornelia Huck Signed-off-by: Michael S. Tsirkin Signed-off-by: Greg Kroah-Hartman

virtio_balloon: init 1st buffer in stats vq

2017-03-31T08:31:45Z

commit fc8653228c8588a120f6b5dad6983b7b61ff669e upstream. When init_vqs runs, virtio_balloon.stats is either uninitialized or contains stale values. The host updates its state with garbage data because it has no way of knowing that this is just a marker buffer used for signaling. This patch updates the stats before pushing the initial buffer. Alternative fixes: * Push an empty buffer in init_vqs. Not easily done with the current virtio implementation and violates the spec "Driver MUST supply the same subset of statistics in all buffers submitted to the statsq". * Push a buffer with invalid tags in init_vqs. Violates the same spec clause, plus "invalid tag" is not really defined. Note: the spec says: When using the legacy interface, the device SHOULD ignore all values in the first buffer in the statsq supplied by the driver after device initialization. Note: Historically, drivers supplied an uninitialized buffer in the first buffer. Unfortunately QEMU does not seem to implement the recommendation even for the legacy interface. Signed-off-by: Ladi Prosek Signed-off-by: Michael S. Tsirkin Signed-off-by: Greg Kroah-Hartman

mm balloon: umount balloon_mnt when removing vb device

2017-03-12T05:41:43Z

commit 9c57b5808c625f4fc93da330b932647eaff321f7 upstream. With CONFIG_BALLOON_COMPACTION=y the kernel will mount balloon_mnt for balloon page migration when we probe a virtio_balloon device. However we do not unmount it when removing the device. Fix this. Fixes: b1123ea6d3b3 ("mm: balloon: use general non-lru movable page feature") Link: http://lkml.kernel.org/r/1486531318-35189-1-git-send-email-xieyisheng1@huawei.com Signed-off-by: Yisheng Xie Acked-by: Minchan Kim Cc: Rafael Aquini Cc: Konstantin Khlebnikov Cc: Gioh Kim Cc: Vlastimil Babka Cc: Michal Hocko Cc: Michael S. Tsirkin Cc: Jason Wang Cc: Hanjun Guo Cc: Xishi Qiu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

Revert "vring: Force use of DMA API for ARM-based systems with legacy devices"

2017-02-09T07:08:28Z

commit 0d5415b489f68b58e1983a53793d25d53098ed4b upstream. This reverts commit c7070619f3408d9a0dffbed9149e6f00479cf43b. 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: c7070619f340 ("vring: Force use of DMA API for ARM-based systems with legacy devices") Reported-by: Robin Murphy Signed-off-by: Will Deacon Signed-off-by: Michael S. Tsirkin Acked-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman

virtio_mmio: Set DMA masks appropriately

2017-02-01T07:33:13Z

commit f7f6634d23830ff74335734fbdb28ea109c1f349 upstream. Once DMA API usage is enabled, it becomes apparent that virtio-mmio is inadvertently relying on the default 32-bit DMA mask, which leads to problems like rapidly exhausting SWIOTLB bounce buffers. Ensure that we set the appropriate 64-bit DMA mask whenever possible, with the coherent mask suitably limited for the legacy vring as per a0be1db4304f ("virtio_pci: Limit DMA mask to 44 bits for legacy virtio devices"). Cc: Andy Lutomirski Cc: Michael S. Tsirkin Reported-by: Jean-Philippe Brucker Fixes: b42111382f0e ("virtio_mmio: Use the DMA API if enabled") Signed-off-by: Robin Murphy Signed-off-by: Michael S. Tsirkin Signed-off-by: Greg Kroah-Hartman

vring: Force use of DMA API for ARM-based systems with legacy devices

2017-02-01T07:33:05Z

commit c7070619f3408d9a0dffbed9149e6f00479cf43b upstream. Booting Linux on an ARM fastmodel containing an SMMU emulation results in an unexpected I/O page fault from the legacy virtio-blk PCI device: [ 1.211721] arm-smmu-v3 2b400000.smmu: event 0x10 received: [ 1.211800] arm-smmu-v3 2b400000.smmu: 0x00000000fffff010 [ 1.211880] arm-smmu-v3 2b400000.smmu: 0x0000020800000000 [ 1.211959] arm-smmu-v3 2b400000.smmu: 0x00000008fa081002 [ 1.212075] arm-smmu-v3 2b400000.smmu: 0x0000000000000000 [ 1.212155] arm-smmu-v3 2b400000.smmu: event 0x10 received: [ 1.212234] arm-smmu-v3 2b400000.smmu: 0x00000000fffff010 [ 1.212314] arm-smmu-v3 2b400000.smmu: 0x0000020800000000 [ 1.212394] arm-smmu-v3 2b400000.smmu: 0x00000008fa081000 [ 1.212471] arm-smmu-v3 2b400000.smmu: 0x0000000000000000 This is because the legacy virtio-blk device is behind an SMMU, so we have consequently swizzled its DMA ops and configured the SMMU to translate accesses. This then requires the vring code to use the DMA API to establish translations, otherwise all transactions will result in fatal faults and termination. Given that ARM-based systems only see an SMMU if one is really present (the topology is all described by firmware tables such as device-tree or IORT), then we can safely use the DMA API for all legacy virtio devices. Modern devices can advertise the prescense of an IOMMU using the VIRTIO_F_IOMMU_PLATFORM feature flag. Cc: Andy Lutomirski Cc: Michael S. Tsirkin Fixes: 876945dbf649 ("arm64: Hook up IOMMU dma_ops") Signed-off-by: Will Deacon Signed-off-by: Michael S. Tsirkin Acked-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman

virtio_ring: mark vring_dma_dev inline

2016-10-30T22:40:08Z

This inline function is unused on configurations where dma_map/unmap are empty macros. Make the function inline to avoid gcc errors because of an unused static function. Signed-off-by: Michael S. Tsirkin