RE: Linux 5.10-rc4; graphics alignment

David Laight
2020-11-20T10:51:49Z

From: Thomas Zimmermann
> Sent: 20 November 2020 10:14
...
> > Is there any way to bisect through the parts of the
> > drm merge patch into v5.10-rc1 ?
> >
> > That ought to be quicker (and less error prone) than
> > the bisect builds I was doing.
> >
> > Note that the stack 'splat' is due to a later change.
> > It is separate from the broken pixel alignment.
> >
> > I actually saw the vga text go 'funny' while the boot
> > was outputting all the [OK] messages (from systemd?)
> > before the graphic login stole tty1 (bloody stupid
> > to use tty1).
> >
> > I don't need to use the failing system today, I'll
> > have another go at isolating the failure.
>
> You can use drm-tip for testing, where many of the DRM patches go through.
>
> https://cgit.freedesktop.org/drm/drm-tip/
>
> It's fairly up-to-date.

Any idea of tags either side of the 5.10 merge?

> I have two systems with AST chips and neither shows any of the symptoms
> you describe; nor do we have such reports about drivers that use a
> similar stack (hibmc, bochs). Could you provide the output of
>
> dmesg | grep drm

[ 2.112303] fb0: switching to astdrmfb from EFI VGA
[ 2.120222] ast 0000:02:00.0: [drm] Using P2A bridge for configuration
[ 2.120233] ast 0000:02:00.0: [drm] AST 2400 detected
[ 2.120247] ast 0000:02:00.0: [drm] Analog VGA only
[ 2.120257] ast 0000:02:00.0: [drm] dram MCLK=408 Mhz type=1 bus_width=16
[ 2.121121] [drm] Initialized ast 0.1.0 20120228 for 0000:02:00.0 on minor 0
[ 2.125838] fbcon: astdrmfb (fb0) is primary device
[ 2.152179] ast 0000:02:00.0: [drm] fb0: astdrmfb frame buffer device
[ 6.061034] systemd[1]: Condition check resulted in Load Kernel Module drm being skipped.

The output is the same for both good and bad kernels.