EL9

[Jacco Ligthart]

All,


As a followup on a mail thread in CentOS ARM dev:

I managed to build most of EL9-beta for armv6.

I am under the impression that it is still quite beta, but this is
probably a good starting point for EL9-final.


There was also a discussion about EL8 and upstream kernel issues. I
guess that we do not see those issues as we use kernels for the vendors
of the boards in stead of RedHat kernels. I do however see that some
odoid kernels miss features that EL9 expects to be includes in the kernel.


Jacco

[Bjarne Saltbaek]

Hi Jacco.

Do you have any armv6 devices (that are not armv7) ?.

Of all the RPI3,RPI4,Odroid,Cubox and Macchiatobin devices I have, I
only have a RPI3 that is armv6. All the other are armv7 or armv8.

So I am sort of leaving the armv5 platform (i found more and more
software that have left armv5 support so I find it hopeless to stay on
armv5).

I have set up my build system to make armv7hl arch's which is best for
my devices. I am almost done with building the EL 8.5 from CentOS. I
even got the Module Build System (MBS) to work and can (re)build all the
modules in koji.

Work in progress at https://koji.dev.saltbaek.dk/koji/

I plan to use pungi to create ISO images and repositories.

When I am done I will upload all the patches to Redsleeve github.

I am still battling with the kernel. I got EL8.3's kernel-4.18.0-193.1.2
patched so it compiles on armv7. Took a week of googling kernel arm
commits and apply them :( EL8.5's kernel-4.18.0-348 is making my hair
grey, but I will get it done at some point.

BR,

Bjarne

[Gordan Bobic]

On Sun, 2 Oct 2022, 22:31 Bjarne Saltbaek, <arnebj...@hotmail.com> wrote:

Hi Jacco.

Do you have any armv6 devices (that are not armv7) ?.

Of all the RPI3,RPI4,Odroid,Cubox and Macchiatobin devices I have, I
only have a RPI3 that is armv6. All the other are armv7 or armv8.

RPi3 is ARMv7.

Only the original RPi1 is ARMv6.

So I am sort of leaving the armv5 platform (i found more and more
software that have left armv5 support so I find it hopeless to stay on
armv5).

I have set up my build system to make armv7hl arch's which is best for
my devices. I am almost done with building the EL 8.5 from CentOS. I
even got the Module Build System (MBS) to work and can (re)build all the
modules in koji.

Work in progress at https://koji.dev.saltbaek.dk/koji/

I plan to use pungi to create ISO images and repositories.

When I am done I will upload all the patches to Redsleeve github.

I am still battling with the kernel. I got EL8.3's kernel-4.18.0-193.1.2
patched so it compiles on armv7. Took a week of googling kernel arm
commits and apply them :( EL8.5's kernel-4.18.0-348 is making my hair
grey, but I will get it done at some point.

IME, eventually you will find that using the RHEL Kernel becomes increasingly hopeless. You would be far better off picking the next up LTS kernel and using that.

Reason I say this is that RH have in the past shown 0 I retest in fixing even mispatch bugs for which fixes are sent to them if they affect anything they don't support, no matter how genuine a bug it is. I hit this back in EL6 days. I cannot imagine things got better since then.

What I do is take the EL .config and use it as a starting point on the next LTS kernel up, and add whatever is needed in terms of hardware support. EL dropped support for some of the hardware I still use (some SAS controllers) and the support for them isn't even in centos+ kernel IIRC, at least on aarch64.

[Jacco Ligthart]

Hi Bjarne,


I have some original raspberry pi's. These are all ARMv6, as are the -
more recent - raspberry pi zero's. I don't have any ARMv5's (never had any)

I also found that it is more and more difficult to build for ARMv5. For
that reason I (re)build RedHat 8 for ARMv6 and recently RedHat 9 as well.

announcement for 9 to follow when all images for all raspberries are
working.


There used to be quite an active community for building CentOS on ARMv7
I think this is their homepage:
https://wiki.centos.org/SpecialInterestGroup/AltArch/armhfp

I remember them also building CentOS8 for ARMv7, but I cannot find that
right now.

The short of it is, that I felt that other people were busy building for
v7 and that it was not useful to redo their work. And also that it made
sense to have a special place for ARMv6 as there are should be so many
pi 1's and zeros around.


Modules, sigh, I really hate them. I'm glad that they quit using them on
RedHat9. I will not spend any more time on that.


And lastly the RedHat kernel. Like Gordan I tried to build the RedHat
kernel earlier. I even succeeded. The main issue is though that RedHat
is backporting many new features and fixes over the course of the
lifetime of a release. They will cherry pick patches to use in their
build. As they do not care about ARMv5-7 they will not necessarily also
patch the same issues for those CPU's. (Actually, I suspect they
actively remove arm stuff from upstream patches).

I found that every time a new kernel was released it took a lot of time
to fix it enough, that it would build again. Specially when there is a
minor RedHat release.

Even then when it builds (and runs) there is no guarantee that
everything that should be fixed in this version actually is ...

My money is on the kernels from the vendors of the boards for running
and on the kernel headers (that actually do build easy) for building RPM's.


Jacco

[Gordan Bobic]

I'd probably go as far as limiting kernels to only two options:

1) Whatever the upstream vendor provides, binary only, provided
unmaintained and unupdated
2) Mainline, with as wide a support as possible. Hardware that isn't
supported in mainline LT release, it won't work.

In aarch64 world, I'm having a reasonably good experience with
mainline kernels, my kernel works on both MP30-AR1 and on the Oracle
Cloud ARM64 VMs.

> --
> You received this message because you are subscribed to the Google Groups "redsleeve-users" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to redsleeve-use...@googlegroups.com.
> To view this discussion on the web, visit https://groups.google.com/d/msgid/redsleeve-users/fd8af78f-89a7-4302-f054-aa282dbff86d%40redsleeve.org.

[Jacco Ligthart]

For raspberries I take the source from github and compile that.

This makes that we can add SELinux, which makes it closer to RedHat than
it would be otherwise.


Jacco

(also works for odroid btw)

[Bjarne Saltbæk]

Hi Jacco.

 

I haven Googled around to see what happened.

But latest EL8 for armhfp in vault.centos.org is 8.1 ☹

 

The community might be active on EL7 but not EL8 (my guess is that the AltArch group ditched CentOS and went over to Rocky Linux).

(And Fedora have “sunset’ed” armhfp and focus only on aarch64)

 

So what I see, I am all alone on CentOS 8.5 armhfp 😊

 

 

And https://armhfp-koji.mbox.centos.org have been taken down

And latest bug reports in bugs.centos.org are from 2020 :-/

 

BR,

Bjarne