MP kernels broken with version 5.4.0-1

[Frank Scheiner <frank.scheiner@web.de>]

Dear all,

I'm unsure if someone already noticed, but it looks like the MP kernels
for the alpha arch are broken since at least 5.4.0-1 ([1]), tested on:

* quad processor ES45 (with 5.4.0-1, 5.7.0-1)
* single processor AS 800 (with 5.7.0-1)
* dual processor DS25 (with 5.4.0-1 and 5.15.0-1)

[1]:
http://snapshot.debian.org/archive/debian-ports/20191229T085938Z/pool-alpha/main/l/linux/linux-image-5.4.0-1-alpha-smp_5.4.6-1_alpha.deb

5.3.x still works fine, tested on:

* DS25 (with 5.3.0-6)
* AS 800 (with 5.3.0-2))

And now guess what, the SP kernel still works, up to 5.15.0-1, and
tested on the DS25.

I assume the multiprocessor alpha buildds should have the same problem,
but for the one I checked it still ran with 5.3.6 [2], though the linked
log is already from 2020.

[2]:
https://buildd.debian.org/status/fetch.php?pkg=ppx-tools-versioned&arch=alpha&ver=5.4.0-1%2Bb2&stamp=1608280942&raw=0

I wonder if there is some current or better live information about the
hardware and software of the buildds available somewhere on the web?

****

If time allows I will try to bisect this issue, but as I am already
behind with figuring out what broke the kernel for UltraSPARC III(i), I
wouldn't mind someone else being faster with bisecting the Alpha MP issue.

****

@Michael:
If you remember my first email to you and this list from early 2017, we
had a similar situation, though the SP kernels were toast back then and
now it's the MP ones. Well, the situation back then was definitely
better for us. :-)

Cheers,
Frank