linux-stable.git/drivers/virtio, branch v3.10.99

virtio: fix memory leak of virtio ida cache layers

2016-03-03T23:06:21+00:00

commit c13f99b7e945dad5273a8b7ee230f4d1f22d3354 upstream.

The virtio core uses a static ida named virtio_index_ida for
assigning index numbers to virtio devices during registration.
The ida core may allocate some internal idr cache layers and
an ida bitmap upon any ida allocation, and all these layers are
truely freed only upon the ida destruction. The virtio_index_ida
is not destroyed at present, leading to a memory leak when using
the virtio core as a module and atleast one virtio device is
registered and unregistered.

Fix this by invoking ida_destroy() in the virtio core module
exit.

Signed-off-by: Suman Anna 
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Greg Kroah-Hartman

virtio_pci: fix virtio spec compliance on restore

2014-11-14T16:47:55+00:00

commit 6fbc198cf623944ab60a1db6d306a4d55cdd820d upstream.

On restore, virtio pci does the following:
+ set features
+ init vqs etc - device can be used at this point!
+ set ACKNOWLEDGE,DRIVER and DRIVER_OK status bits

This is in violation of the virtio spec, which
requires the following order:
- ACKNOWLEDGE
- DRIVER
- init vqs
- DRIVER_OK

This behaviour will break with hypervisors that assume spec compliant
behaviour.  It seems like a good idea to have this patch applied to
stable branches to reduce the support butden for the hypervisors.

Cc: Amit Shah 
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Rusty Russell 
Signed-off-by: Greg Kroah-Hartman

virtio_balloon: don't softlockup on huge balloon changes.

2014-05-13T11:59:41+00:00

commit 1f74ef0f2d7d692fcd615621e0e734c3e7771413 upstream.

When adding or removing 100G from a balloon:

    BUG: soft lockup - CPU#0 stuck for 22s! [vballoon:367]

We have a wait_event_interruptible(), but the condition is always true
(more ballooning to do) so we don't ever sleep.  We also have a
wait_event() for the host to ack, but that is also always true as QEMU
is synchronous for balloon operations.

Reported-by: Gopesh Kumar Chaudhary 
Signed-off-by: Rusty Russell 
Signed-off-by: Greg Kroah-Hartman

virtio: support unlocked queue poll

2013-07-28T23:29:55+00:00

[ Upstream commit cc229884d3f77ec3b1240e467e0236c3e0647c0c ]

This adds a way to check ring empty state after enable_cb outside any
locks. Will be used by virtio_net.

Note: there's room for more optimization: caller is likely to have a
memory barrier already, which means we might be able to get rid of a
barrier here.  Deferring this optimization until we do some
benchmarking.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

virtio_balloon: leak_balloon(): only tell host if we got pages deflated

2013-07-25T21:07:31+00:00

commit 8c6bab4f3874d31804a00782c48a8f244a0d3cc0 upstream.

balloon_page_dequeue() can return NULL.  If it does for the first page
being freed then leak_balloon() will create a scatter list with len=0.
Which in turn seems to generate an invalid virtio request.

I didn't get this in practice, I found it by code review.  On the other
hand, such an invalid virtio request will cause errors in QEMU and
fill_balloon() also performs the same check implemented by this commit.

This bug was introduced in e2250429.

Signed-off-by: Luiz Capitulino 
Acked-by: Rafael Aquini 
Signed-off-by: Andrew Morton 
Signed-off-by: Rusty Russell 
Signed-off-by: Greg Kroah-Hartman

virtio_balloon: use simplified virtqueue accessors.

2013-03-20T05:15:06+00:00

We never add buffers with input and output parts, so use the new accessors.

Signed-off-by: Rusty Russell

virtio_ring: virtqueue_add_outbuf / virtqueue_add_inbuf.

2013-03-20T05:14:52+00:00

These are specialized versions of virtqueue_add_buf(), which cover
over 80% of cases and are far clearer.

In particular, the scatterlists passed to these functions don't have
to be clean (ie. we ignore end markers).

Signed-off-by: Rusty Russell

virtio_ring: virtqueue_add_sgs, to add multiple sgs.

2013-03-20T05:13:29+00:00

virtio_scsi can really use this, to avoid the current hack of copying
the whole sg array.  Some other things get slightly neater, too.

This causes a slowdown in virtqueue_add_buf(), which is implemented as
a wrapper.  This is addressed in the next patches.

for i in `seq 50`; do /usr/bin/time -f 'Wall time:%e' ./vringh_test --indirect --eventidx --parallel --fast-vringh; done 2>&1 | stats --trim-outliers:

Before:
	Using CPUS 0 and 3
	Guest: notified 0, pinged 39009-39063(39062)
	Host: notified 39009-39063(39062), pinged 0
	Wall time:1.700000-1.950000(1.723542)

After:
	Using CPUS 0 and 3
	Guest: notified 0, pinged 39062-39063(39063)
	Host: notified 39062-39063(39063), pinged 0
	Wall time:1.760000-2.220000(1.789167)

Signed-off-by: Rusty Russell 
Reviewed-by: Wanlong Gao 
Reviewed-by: Asias He

virtio_ring: expose virtio barriers for use in vringh.

2013-03-20T03:30:41+00:00

The host side of ring needs this logic too.

Signed-off-by: Rusty Russell

Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

2013-02-26T22:49:12+00:00

Pull virtio updates from Rusty Russell:
 "All trivial, thanks to the stuff which didn't quite make it time"

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  virtio_console: Initialize guest_connected=true for rproc_serial
  virtio: use module_virtio_driver.
  virtio: Add module driver macro for virtio drivers.
  virtio_console: Use virtio device index to generate port name
  virtio: make pci_device_id const
  virtio: make config_ops const
  virtio-mmio: fix wrong comment about register offset
  virtio_console: Let unconnected rproc device receive data.