linux/drivers/virtio
Cornelia Huck cf94db2190 virtio: Honour 'may_reduce_num' in vring_create_virtqueue
vring_create_virtqueue() allows the caller to specify via the
may_reduce_num parameter whether the vring code is allowed to
allocate a smaller ring than specified.

However, the split ring allocation code tries to allocate a
smaller ring on allocation failure regardless of what the
caller specified. This may cause trouble for e.g. virtio-pci
in legacy mode, which does not support ring resizing. (The
packed ring code does not resize in any case.)

Let's fix this by bailing out immediately in the split ring code
if the requested size cannot be allocated and may_reduce_num has
not been specified.

While at it, fix a typo in the usage instructions.

Fixes: 2a2d1382fe ("virtio: Add improved queue allocation API")
Cc: stable@vger.kernel.org # v4.6+
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
2019-04-08 17:05:52 -04:00
..
Kconfig virtio: make VIRTIO a menuconfig to ease disabling it all 2018-02-01 16:26:43 +02:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
virtio.c virtio: hint if callbacks surprisingly might sleep 2019-03-06 11:19:57 -05:00
virtio_balloon.c virtio_balloon: remove the unnecessary 0-initialization 2019-03-06 11:19:33 -05:00
virtio_input.c virtio: wrap find_vqs 2017-05-02 23:41:42 +03:00
virtio_mmio.c virtio: don't allocate vqs when names[i] = NULL 2019-01-14 20:15:19 -05:00
virtio_pci_common.c virtio_pci: fix a NULL pointer reference in vp_del_vqs 2019-04-08 08:40:58 -04:00
virtio_pci_common.h virtio: Make vp_set_vq_affinity() take a mask. 2018-08-11 12:02:18 -07:00
virtio_pci_legacy.c virtio: remove deprecated VIRTIO_PCI_CONFIG() 2018-12-19 18:23:49 -05:00
virtio_pci_modern.c virtio_pci: support enabling VFs 2018-06-12 04:59:29 +03:00
virtio_ring.c virtio: Honour 'may_reduce_num' in vring_create_virtqueue 2019-04-08 17:05:52 -04:00