tree 35d3cf4b2942405fdaf6c2c05d69fc3b25d3a4b6
parent bdb86d0c0c9585b6750d1992f7f19f46f82e8da8
author Marc Zyngier <maz@kernel.org> 1630065245 +0100
committer Will Deacon <will@kernel.org> 1630421273 +0100

virtio/pci: Size the MSI-X bar according to the number of MSI-X

Since 45d3b59e8c45 ("kvm tools: Increase amount of possible interrupts
per PCI device"), the number of MSI-S has gone from 4 to 33.

However, the corresponding storage hasn't been upgraded, and writing
to the MSI-X table is a pretty risky business. Now that the Linux
kernel writes to *all* MSI-X entries before doing anything else
with the device, kvmtool dies a horrible death.

Fix it by properly defining the size of the MSI-X bar, and make
Linux great again.

This includes some fixes the PBA region decoding, as well as minor
cleanups to make this code a bit more maintainable.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Link: https://lore.kernel.org/r/20210827115405.1981529-1-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>