virtio: mmio: fix signature checking for BE guests

As virtio-mmio config registers are specified to be little-endian,
using readl() to read the magic value and then memcmp() to check it
fails on BE (as readl() has an implicit swab).

Fix it by encoding the magic value as an integer instead of a string.

Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Marc Zyngier 2013-11-05 21:21:28 +10:30 committed by Rusty Russell
parent 2342d6a651
commit 4ae8537072

View File

@ -471,7 +471,7 @@ static int virtio_mmio_probe(struct platform_device *pdev)
/* Check magic value */
magic = readl(vm_dev->base + VIRTIO_MMIO_MAGIC_VALUE);
if (memcmp(&magic, "virt", 4) != 0) {
if (magic != ('v' | 'i' << 8 | 'r' << 16 | 't' << 24)) {
dev_warn(&pdev->dev, "Wrong magic value 0x%08lx!\n", magic);
return -ENODEV;
}