RE: Linux 5.10-rc4; graphics alignment

[David Laight]

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.

	David

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