On Thu, 21 Mar 2019 at 12:40, Laszlo Ersek <lersek(a)redhat.com> wrote:
In brief, the regression is that the aarch64 system emulator now
lists
the "virtio-vga" device for the "virt" machine type:
$ qemu-system-aarch64 -M virt -device \? | grep virtio-vga
name "virtio-vga", bus PCI
Here's where I think the issue was introduced:
(1) In commit 82f5181777eb ("kconfig: introduce kconfig files",
2019-03-07), VIRTIO_VGA was introduced simply as a bool (with no other
clauses) in "hw/display/Kconfig".
(2) In commit 7c28b925b7e1 ("build: convert pci.mak to Kconfig",
2019-03-07), VIRTIO_VGA received the following clauses:
default y if PCI_DEVICES
depends on VIRTIO_PCI
select VGA
This is too lax, because it permits virtio-vga for aarch64, while that
shouldn't happen (and it doesn't matches the previous state of the tree).
(3) In commit b42075bb7767 ("virtio: express virtio dependencies with
Kconfig", 2019-03-07), the determination of virtio-vga was switched to
the Kconfig system. Importantly, in this patch, the line
CONFIG_VIRTIO_VGA=y
was removed *only* from the following file:
default-configs/i386-softmmu.mak
(4) Both of the remaining instances of
CONFIG_VIRTIO_VGA=y
were then removed in commit 9483cf27dd36 ("hppa-softmmu.mak: express
dependencies with Kconfig", 2019-03-07) and commit 87f9108bad0c ("ppc64:
Express dependencies of 'pseries' and 'powernv' machines with
kconfig",
2019-03-07), from files
default-configs/hppa-softmmu.mak
default-configs/ppc64-softmmu.mak
respectively.
Therefore I think commit 7c28b925b7e1 has the bug. The VIRTIO_VGA
restriction
depends on VIRTIO_PCI
should now be replaced with
depends on VIRTIO_PCI && (PC || DINO || PSERIES)
Should it? What makes the virtio-vga device only
suitable for those three machines?
thanks
-- PMM