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| author | Stephan Gerhold <stephan.gerhold@kernkonzept.com> | 2022-06-21 14:06:21 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-07-21 21:42:46 +0300 |
| commit | 0de3313bc984b2cf399f673c61edf49afafa9592 (patch) | |
| tree | f8da23fc658e53b6e4d6141335d9fef915cf8452 | |
| parent | f69d10db9940ddd012b167f639ef17f81ab3140d (diff) | |
| download | linux-0de3313bc984b2cf399f673c61edf49afafa9592.tar.xz | |
virtio_mmio: Restore guest page size on resume
[ Upstream commit e0c2ce8217955537dd5434baeba061f209797119 ]
Virtio devices might lose their state when the VMM is restarted
after a suspend to disk (hibernation) cycle. This means that the
guest page size register must be restored for the virtio_mmio legacy
interface, since otherwise the virtio queues are not functional.
This is particularly problematic for QEMU that currently still defaults
to using the legacy interface for virtio_mmio. Write the guest page
size register again in virtio_mmio_restore() to make legacy virtio_mmio
devices work correctly after hibernation.
Signed-off-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com>
Message-Id: <20220621110621.3638025-3-stephan.gerhold@kernkonzept.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/virtio/virtio_mmio.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c index d0a7f69782a4..0cd9e29d7f98 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -505,6 +505,9 @@ static int virtio_mmio_restore(struct device *dev) { struct virtio_mmio_device *vm_dev = dev_get_drvdata(dev); + if (vm_dev->version == 1) + writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_GUEST_PAGE_SIZE); + return virtio_device_restore(&vm_dev->vdev); } |