Setting up a Hurd build node

Setting up a Hurd build node

[Ricardo Wurmus]

Hi Guix,

I just built Guix in a Debian GNU/Hurd VM and wanted to set it up as a
build node.  I applied a patch to use the i586-gnu bootstrap binaries
from my previous attempt in late 2018, which are published at
https://berlin.guixsd.org/guix/bootstrap/i586-gnu/20180908/.  These were
built with the old patched glibc 2.23.  (The patch to add the bootstrap
binaries is 3.5MB in size because it includes the statically linked
binaries, so I’m not attaching it here.)

Unfortunately, using the build users does not work:

--8<---------------cut here---------------start------------->8---
root@debian:~/guix-1.0.0# ./pre-inst-env guix-daemon --build-users-group=guixbuild --disable-chroot &
root@debian:~/guix-1.0.0# ./pre-inst-env guix build -S hello
madvise failed: Function not implemented
madvise failed: Function not implemented
madvise failed: Function not implemented
madvise failed: Function not implemented
substitute: madvise failed: Function not implemented
substitute: guix substitute: warning: ACL for archive imports seems to be uninitialized, substitutes may be unavailable
The following derivation will be built:
   /gnu/store/qihk8cf98xqc7q577wb2nc5axy2ryp8m-hello-2.10.tar.gz.drv
error: cannot kill processes for uid `999': Operation not permitted
guix build: error: cannot kill processes for uid `999': failed with exit code 1
--8<---------------cut here---------------end--------------->8---

Uid 999 belongs to guixbuilder01.  (The gid for the guixbuild group is
also 999.)

I also tried building “hello”, but I only get the message

    madvise failed: Function not implemented

printed endlessly.  (This is probably harmless, but nothing else
happens.)

--
Ricardo

Re: Setting up a Hurd build node

[Ricardo Wurmus]

Ricardo Wurmus <rekado@elephly.net> writes:

> I also tried building “hello”, but I only get the message
>
>     madvise failed: Function not implemented
>
> printed endlessly.  (This is probably harmless, but nothing else
> happens.)

It’s not endless after all.  The VM has 10G of RAM (I don’t know if all
of this is usable by the Hurd).  Eventually Guile runs out of memory:

     madvise failed: Function not implemented                                              
     madvise failed: Function not implemented                                              
     madvise failed: Function not implemented                                              
     madvise failed: Function not implemented                                              
     madvise failed: Function not implemented                                              
     madvise failed: Function not implemented                                              
            no more room in f5817750 (/usr/local/bin/guile(18046))                         
     allocate_stack failed: Cannot allocate memory                                         
     Warning: Unwind-only `stack-overflow' exception; skipping pre-unwind handler.         
     no more room in f5817750 (/usr/local/bin/guile(18046))                                
     allocate_stack failed: Cannot allocate memory                                         
     Warning: Unwind-only `stack-overflow' exception; skipping pre-unwind handler.         
     no more room in f5817750 (/usr/local/bin/guile(18046))                                
     allocate_stack failed: Cannot allocate memory                                         
     Warning: Unwind-only `stack-overflow' exception; skipping pre-unwind handler.         

That’s when it finally aborts.

-- 
Ricardo

Re: Setting up a Hurd build node

[Ludovic Courtès]

Hello,

Ricardo Wurmus <rekado@elephly.net> skribis:

> I just built Guix in a Debian GNU/Hurd VM and wanted to set it up as a
> build node.  I applied a patch to use the i586-gnu bootstrap binaries
> from my previous attempt in late 2018, which are published at
> https://berlin.guixsd.org/guix/bootstrap/i586-gnu/20180908/.  These were
> built with the old patched glibc 2.23.  (The patch to add the bootstrap
> binaries is 3.5MB in size because it includes the statically linked
> binaries, so I’m not attaching it here.)

I think we should fix our cross-compiled bootstrap Guile so we can
finally upload bootstrap binaries to ftp.gnu.org:

  https://issues.guix.info/issue/34427
  https://lists.gnu.org/archive/html/guix-devel/2018-12/msg00364.html

> root@debian:~/guix-1.0.0# ./pre-inst-env guix-daemon --build-users-group=guixbuild --disable-chroot &
> root@debian:~/guix-1.0.0# ./pre-inst-env guix build -S hello
> madvise failed: Function not implemented

This warning comes from Guile; it’s fixed in our guile 2.2 package and
upstream.

> The following derivation will be built:
>    /gnu/store/qihk8cf98xqc7q577wb2nc5axy2ryp8m-hello-2.10.tar.gz.drv
> error: cannot kill processes for uid `999': Operation not permitted
> guix build: error: cannot kill processes for uid `999': failed with exit code 1

EPERM comes from ‘waitpid’; weird!

> Uid 999 belongs to guixbuilder01.  (The gid for the guixbuild group is
> also 999.)
>
> I also tried building “hello”, but I only get the message
>
>     madvise failed: Function not implemented
>
> printed endlessly.  (This is probably harmless, but nothing else
> happens.)

Looks like the bootstrap Guile is broken somehow.

Ludo’.

Re: Setting up a Hurd build node

[Ricardo Wurmus]

Ludovic Courtès <ludo@gnu.org> writes:

> Hello,
>
> Ricardo Wurmus <rekado@elephly.net> skribis:
>
>> I just built Guix in a Debian GNU/Hurd VM and wanted to set it up as a
>> build node.  I applied a patch to use the i586-gnu bootstrap binaries
>> from my previous attempt in late 2018, which are published at
>> https://berlin.guixsd.org/guix/bootstrap/i586-gnu/20180908/.  These were
>> built with the old patched glibc 2.23.  (The patch to add the bootstrap
>> binaries is 3.5MB in size because it includes the statically linked
>> binaries, so I’m not attaching it here.)
>
> I think we should fix our cross-compiled bootstrap Guile so we can
> finally upload bootstrap binaries to ftp.gnu.org:
>
>   https://issues.guix.info/issue/34427
>   https://lists.gnu.org/archive/html/guix-devel/2018-12/msg00364.html

The new cross-compiled bootstrap Guile is 2.2; for older architectures
it’s 2.0.

I made it work simply by changing all references to “2.0” in “raw-build”
of (gnu packages bootstrap) to “2.2” because the bootstrap Guile really
is version 2.2.  Prior to that the bootstrap Guile would segfault.

>> root@debian:~/guix-1.0.0# ./pre-inst-env guix-daemon --build-users-group=guixbuild --disable-chroot &
>> root@debian:~/guix-1.0.0# ./pre-inst-env guix build -S hello
>> madvise failed: Function not implemented
>
> This warning comes from Guile; it’s fixed in our guile 2.2 package and
> upstream.
>
>> The following derivation will be built:
>>    /gnu/store/qihk8cf98xqc7q577wb2nc5axy2ryp8m-hello-2.10.tar.gz.drv
>> error: cannot kill processes for uid `999': Operation not permitted
>> guix build: error: cannot kill processes for uid `999': failed with exit code 1
>
> EPERM comes from ‘waitpid’; weird!
>
>> Uid 999 belongs to guixbuilder01.  (The gid for the guixbuild group is
>> also 999.)

I punted by running the daemon with only “guix-daemon --disable-chroot”,
no build users group at all.  Of course, perform-download doesn’t like
that we’re downloading things as root, so I disabled the assertion…

>> I also tried building “hello”, but I only get the message
>>
>>     madvise failed: Function not implemented
>>
>> printed endlessly.  (This is probably harmless, but nothing else
>> happens.)
>
> Looks like the bootstrap Guile is broken somehow.

I replaced the bootstrap binaries with more recent ones.  I also had to
disable set-thread-name (because the Hurd doesn’t have it) and took a
step back to build something simpler:

    /pre-inst-env  guix build -e '(@@ (gnu packages commencement) gnu-make-boot0))'

This eventually calls

    /gnu/store/dqlhjyvg0n8v1kdvwfpliqy46n7kpjqb-bootstrap-binaries-0/bin/tar cvfa \
       /gnu/store/p278mqb3aa0xrkrrw4rg1fxbb19hbdyh-make-4.2.1.tar.xz \
       --mtime=@0 --owner=root --group=root --sort=name \
       make-4.2.1

which segfaults.  Turns out that it doesn’t segfault after removing
“--mtime=@0” from the arguments.

Weird!  This is all very familiar, because that’s where I stopped when I
last tried all of this.  I gave up when I couldn’t figure out why tar
segfaulted.

--
Ricardo

Re: Setting up a Hurd build node

[Jonathan Brielmaier]

Am 08.05.19 um 00:12 schrieb Ricardo Wurmus> Weird!  This is all very
familiar, because that’s where I stopped when I
> last tried all of this.  I gave up when I couldn’t figure out why tar
> segfaulted.

Maybe you could include the bug-hurd@gnu.org mailing list or ask Hurd
hackers directly :)