ACK: Re: [Disco] Re-enable DRM Support for bochs (qemu stdvga)

[Timo Aaltonen]

On 29.3.2019 17.04, Timo Aaltonen wrote:
> On 29.3.2019 16.35, Thomas Lamprecht wrote:
>> BugLink: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1795857
>>
>> [Impact]
>> Booting a Ubuntu with Cosmic kernel inside a QEMU VM with 'stdvga' as display
>> hangs on gdm unit, display stays black with a single shell cursor blinking in
>> the upper edge. If switching same VM to another display tipe (e.g., qxl) allows
>> it to boot just fine.
>>
>> [Fix]
>> Re-enable the DRM_BOCHS driver to be build as module.
>>
>> [Test Case]
>> Start an installed Ubuntu 19.04 (e.g., from Beta or weekly built ISOs) inside a
>> VM with display 'stdvga'. The installer itself will work, but once you reboot
>> you get a broken system. With this patch _and_ the 'blacklist bochs-drm' entry
>> from 'kmod' package shipped '/etc/modprobe.d/blacklist-framebuffer.conf' removed
>> the system boots as expected, gdm can startup and one can login through a
>> graphical session
>>
>> [Regression Potential]
>> Low. Even the original bug report pondered if it would be better to fix
>> bochs-drm instead of plain disabling it. I could not relate to it, but I do not
>> have PowerPC hardware to test it. I still mark regression potential low as the
>> driver can get simply blacklisted for cases it isn't wanted or makes problems.
>>
>>
>> Thomas Lamprecht (1):
>>   UBUNTU: [Config] Reenable DRM_BOCHS as module
>>
>>  debian.master/config/annotations | 3 +--
>>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> Hi, I sent a patch for this last year, and bochs was finally recently
> tested to work fine on ppc64el. Doesn't matter which one actually is
> applied, but at least your explanation is more verbose, so ACK.

actually, I think my patch was more complete, it had this hunk too:

diff --git a/debian.master/config/config.common.ubuntu
b/debian.master/config/config.common.ubuntu
index bdece4b92c89..e6e1f5d34ea1 100644
--- a/debian.master/config/config.common.ubuntu
+++ b/debian.master/config/config.common.ubuntu
@@ -2315,7 +2315,7 @@ CONFIG_DRM_ARM=y
 CONFIG_DRM_ARMADA=m
 CONFIG_DRM_AST=m
 CONFIG_DRM_ATMEL_HLCDC=m
-# CONFIG_DRM_BOCHS is not set
+CONFIG_DRM_BOCHS=m
 CONFIG_DRM_BRIDGE=y
 CONFIG_DRM_CDNS_DSI=m
 CONFIG_DRM_CIRRUS_QEMU=m


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