linux-stable.git/drivers/virtio, branch v5.3.16

virtio_balloon: fix shrinker count

2019-11-29T09:07:45+00:00

commit c9a6820fc0da2603be3054ee7590eb9f350508a7 upstream.

Instead of multiplying by page order, virtio balloon divided by page
order. The result is that it can return 0 if there are a bit less
than MAX_ORDER - 1 pages in use, and then shrinker scan won't be called.

Cc: stable@vger.kernel.org
Fixes: 71994620bb25 ("virtio_balloon: replace oom notifier with shrinker")
Signed-off-by: Wei Wang 
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: David Hildenbrand 
Signed-off-by: Greg Kroah-Hartman

virtio_ring: fix return code on DMA mapping fails

2019-11-29T09:07:45+00:00

commit f7728002c1c7bfa787b276a31c3ef458739b8e7c upstream.

Commit 780bc7903a32 ("virtio_ring: Support DMA APIs")  makes
virtqueue_add() return -EIO when we fail to map our I/O buffers. This is
a very realistic scenario for guests with encrypted memory, as swiotlb
may run out of space, depending on it's size and the I/O load.

The virtio-blk driver interprets -EIO form virtqueue_add() as an IO
error, despite the fact that swiotlb full is in absence of bugs a
recoverable condition.

Let us change the return code to -ENOMEM, and make the block layer
recover form these failures when virtio-blk encounters the condition
described above.

Cc: stable@vger.kernel.org
Fixes: 780bc7903a32 ("virtio_ring: Support DMA APIs")
Signed-off-by: Halil Pasic 
Tested-by: Michael Mueller 
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Greg Kroah-Hartman

virtio_ring: fix stalls for packed rings

2019-11-06T12:09:18+00:00

commit 40ce7919d8730f5936da2bc8a21b46bd07db6411 upstream.

When VIRTIO_F_RING_EVENT_IDX is negotiated, virtio devices can
use virtqueue_enable_cb_delayed_packed to reduce the number of device
interrupts.  At the moment, this is the case for virtio-net when the
napi_tx module parameter is set to false.

In this case, the virtio driver selects an event offset and expects that
the device will send a notification when rolling over the event offset
in the ring.  However, if this roll-over happens before the event
suppression structure update, the notification won't be sent. To address
this race condition the driver needs to check wether the device rolled
over the offset after updating the event suppression structure.

With VIRTIO_F_RING_PACKED, the virtio driver did this by reading the
flags field of the descriptor at the specified offset.

Unfortunately, checking at the event offset isn't reliable: if
descriptors are chained (e.g. when INDIRECT is off) not all descriptors
are overwritten by the device, so it's possible that the device skipped
the specific descriptor driver is checking when writing out used
descriptors. If this happens, the driver won't detect the race condition
and will incorrectly expect the device to send a notification.

For virtio-net, the result will be a TX queue stall, with the
transmission getting blocked forever.

With the packed ring, it isn't easy to find a location which is
guaranteed to change upon the roll-over, except the next device
descriptor, as described in the spec:

        Writes of device and driver descriptors can generally be
        reordered, but each side (driver and device) are only required to
        poll (or test) a single location in memory: the next device descriptor after
        the one they processed previously, in circular order.

while this might be sub-optimal, let's do exactly this for now.

Cc: stable@vger.kernel.org
Cc: Jason Wang 
Fixes: f51f982682e2a ("virtio_ring: leverage event idx in packed ring")
Signed-off-by: Marvin Liu 
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Greg Kroah-Hartman

virtio_ring: fix unmap of indirect descriptors

2019-09-09T14:43:15+00:00

The function virtqueue_add_split() DMA-maps the scatterlist buffers. In
case a mapping error occurs the already mapped buffers must be unmapped.
This happens by jumping to the 'unmap_release' label.

In case of indirect descriptors the release is wrong and may leak kernel
memory. Because the implementation assumes that the head descriptor is
already mapped it starts iterating over the descriptor list starting
from the head descriptor. However for indirect descriptors the head
descriptor is never mapped in case of an error.

The fix is to initialize the start index with zero in case of indirect
descriptors and use the 'desc' pointer directly for iterating over the
descriptor chain.

Signed-off-by: Matthias Lange 
Signed-off-by: Michael S. Tsirkin

Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2019-07-19T17:42:02+00:00

Pull vfs mount updates from Al Viro:
 "The first part of mount updates.

  Convert filesystems to use the new mount API"

* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  mnt_init(): call shmem_init() unconditionally
  constify ksys_mount() string arguments
  don't bother with registering rootfs
  init_rootfs(): don't bother with init_ramfs_fs()
  vfs: Convert smackfs to use the new mount API
  vfs: Convert selinuxfs to use the new mount API
  vfs: Convert securityfs to use the new mount API
  vfs: Convert apparmorfs to use the new mount API
  vfs: Convert openpromfs to use the new mount API
  vfs: Convert xenfs to use the new mount API
  vfs: Convert gadgetfs to use the new mount API
  vfs: Convert oprofilefs to use the new mount API
  vfs: Convert ibmasmfs to use the new mount API
  vfs: Convert qib_fs/ipathfs to use the new mount API
  vfs: Convert efivarfs to use the new mount API
  vfs: Convert configfs to use the new mount API
  vfs: Convert binfmt_misc to use the new mount API
  convenience helper: get_tree_single()
  convenience helper get_tree_nodev()
  vfs: Kill sget_userns()
  ...

Merge tag 'libnvdimm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2019-07-18T17:52:08+00:00

Pull libnvdimm updates from Dan Williams:
 "Primarily just the virtio_pmem driver:

   - virtio_pmem

     The new virtio_pmem facility introduces a paravirtualized
     persistent memory device that allows a guest VM to use DAX
     mechanisms to access a host-file with host-page-cache. It arranges
     for MAP_SYNC to be disabled and instead triggers a host fsync()
     when a 'write-cache flush' command is sent to the virtual disk
     device.

   - Miscellaneous small fixups"

* tag 'libnvdimm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  virtio_pmem: fix sparse warning
  xfs: disable map_sync for async flush
  ext4: disable map_sync for async flush
  dax: check synchronous mapping is supported
  dm: enable synchronous dax
  libnvdimm: add dax_dev sync flag
  virtio-pmem: Add virtio pmem driver
  libnvdimm: nd_region flush callback support
  libnvdimm, namespace: Drop uuid_t implementation detail

virtio-mmio: add error check for platform_get_irq

2019-07-11T20:22:29+00:00

in vm_find_vqs() irq has a wrong type
so, in case of no IRQ resource defined,
wrong parameter will be passed to request_irq()

Signed-off-by: Ihor Matushchak 
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Ivan T. Ivanov

virtio-pmem: Add virtio pmem driver

2019-07-05T22:19:10+00:00

This patch adds virtio-pmem driver for KVM guest.

Guest reads the persistent memory range information from
Qemu over VIRTIO and registers it on nvdimm_bus. It also
creates a nd_region object with the persistent memory
range information so that existing 'nvdimm/pmem' driver
can reserve this into system memory map. This way
'virtio-pmem' driver uses existing functionality of pmem
driver to register persistent memory compatible for DAX
capable filesystems.

This also provides function to perform guest flush over
VIRTIO from 'pmem' driver when userspace performs flush
on DAX memory range.

Signed-off-by: Pankaj Gupta 
Reviewed-by: Yuval Shaia 
Acked-by: Michael S. Tsirkin 
Acked-by: Jakub Staron 
Tested-by: Jakub Staron 
Reviewed-by: Cornelia Huck 
Signed-off-by: Dan Williams

virtio: Fix indentation of VIRTIO_MMIO

2019-05-27T15:08:22+00:00

VIRTIO_MMIO config option block starts with a space, fix that.

Signed-off-by: Fabrizio Castro 
Signed-off-by: Michael S. Tsirkin

vfs: Convert virtio_balloon to use the new mount API

2019-05-25T22:06:15+00:00

Convert the virtio_balloon filesystem to the new internal mount API as the old
one will be obsoleted and removed.  This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

Signed-off-by: David Howells 
cc: "Michael S. Tsirkin" 
cc: Jason Wang 
cc: virtualization@lists.linux-foundation.org
Signed-off-by: Al Viro