sgabios outputs incorrect video modes

[Herbie Robinson]

When run with a bootstrap loader that uses int 0x10 with 0x1301 in %ax, incorrect video modes are output to the serial port. I believe the VGA image will be correct. This might also affect the returned values for some interrupts.

This is caused because the set_cursor_position routine fails to save and restore %bx.

I'm working on a fix for this.

[Herbie Robinson (hrob)]

I think I have submitted the fix to the qemu development list, but have no way to be sure it made it past Stratus' corporate firewall. If it didn't make it (or if that was the wrong place to send it), please let me know.

TIA

[Herbie Robinson (hrob)]

I don't think my e-mailed patch got through... I'm going to keep trying, but in case anyone needs the patch in the interim...

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "0001-SGABIOS-fix-wrong-video-attrs-for-int-10h-ah-13h.patch" seems to be a patch. If it isn't, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are a member of the ~ubuntu-reviewers, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issues please contact him.]

[Herbie Robinson (hrob)]

That patch is wrong. The correct patch has been submitted and checked on the QEMU mailing lists

(http://patchwork.ozlabs.org/patch/737446/).

[Nathan Rennie-Waldock (nathan-renniewaldock)]

Any chance of getting this patch included?
I've deleted the incorrect patch and attached the correct one (taken from QEMU's sgabios repo).

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Thomas Huth (th-huth)]

Looks like the fix has been included in QEMU's sgabios repository here:

 https://git.qemu.org/?p=sgabios.git;a=commitdiff;h=cbaee52287e5f32373181cf

And the binary in the QEMU repository has been updated here:

 https://git.qemu.org/?p=qemu.git;a=commitdiff;h=c8c33fca88fc3ab8a5e4b

So this fix is included in QEMU since version 2.10.

[Nathan Rennie-Waldock (nathan-renniewaldock)]

Fixed in qemu, yes. But not Ubuntu. Ubuntu strips prebuilt files from qemu and builds them from source. For sgabios, using the abandoned source from Google code.

[Herbie Robinson (hrob)]

I believe QEMU has handed ownership of this off to coreboot. Which makes sense.

https://review.coreboot.org/cgit/sgabios.git