Re: Kernel Regression: Wallstreet (was Re: OldWorld ROM Macintoshes)

Stan:

How did you test out all these kernels?  I was trying to do so by
downloading various kernels at
https://snapshot.debian.org/binary/linux-image-powerpc/ and installing
them with dpkg, but since they didn't generate config files in /boot
I'm unable to create vmlinux or initrd.img files for BootX.

On Wed, 2025-09-03 at 19:27 -0600, Stan Johnson wrote:
> The only kernel where I'm seeing a system hang on the Wallsteet 
> (framebuffer console blank, backlight on, system doesn't boot) is 
> vmlinux-6.6.3+deb14-powerpc. I don't see that failure with any of the
> mainline kernels that I checked.
> 
> With mainline kernels, I see two failure modes:
> 
> 1) The framebuffer console freezes at the BootX screen in Mac OS, but
> Linux still boots and the system can be accessed over the network.
> 2) X11 initiation fails, but the system reaches a text login at the 
> framebuffer console.
> 
> There appears to be a kernel regression between v6.2-rc1 and v6.2-
> rc8:
> 
> v6.2-rc1  : X11 works
> v6.2-rc8  : failure mode 1
> 
> There may be a second issue (or perhaps a fix of failure mode 1 that 
> triggered failure mode 2) between v6.4-rc1 and v6.4-rc7:
> 
> v6.4-rc1  : failure mode 1
> v6.4-rc7  : failure mode 2
> 
> I'll send another update in a few days after doing a kernel bisect.
> 
> -----
> 
> v5.18     : X11 works
> v6.1      : X11 works
> v6.2-rc1  : X11 works
> v6.2-rc8  : failure mode 1
> v6.2      : failure mode 1
> v6.4-rc1  : failure mode 1
> v6.4-rc7  : failure mode 2
> v6.4      : failure mode 2
> v6.6      : failure mode 2
> v6.16     : failure mode 2
> v6.17-rc4 : failure mode 2