[Bug 1886814] Re: posix_spawn usage in gnu make causes failures on s390x

[Dimitri John Ledkov]

> Is this a native s390x build, or something qemu-user? Thanks.

That's a very good question.

The failing autopkgtest, was run on an LPAR, which is running OpenStack
Nova, which launched qemu-system kvm, v5.4 Ubuntu kernel, and then run
make inside that.

I will double check if those old builds of make & autopkgtest reproduced
the issue just on an LPAR without qemu in between. I believe they did,
but don't have the logs anymore.

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to glibc in Ubuntu.
https://bugs.launchpad.net/bugs/1886814

Title:
  posix_spawn usage in gnu make causes failures on s390x

Status in Ubuntu on IBM z Systems:
  New
Status in glibc package in Ubuntu:
  New
Status in linux package in Ubuntu:
  Incomplete
Status in make-dfsg package in Ubuntu:
  New

Bug description:
  posix_spawn usage in gnu make causes failures on s390x

  Recently in gnu-make v4.3 https://paste.ubuntu.com/p/tYhbJFKN76/ it
  started to use posix_spawn, instead of fork()/exec().

  This has caused failure of an unrelated package flatpak-builder
  autopkgtests on s390x only, like so

    echo Building
    make: echo: Operation not permitted
    make: *** [Makefile:2: all] Error 127

  Julian Klaude investigated this in-depth. His earlier research also
  indicated that this is a heisenbug, if one tries to print to stderr
  before printing to stdout, no issue occurs.

  We are configuring GNU make to be build with --disable-posix-spawn on
  s390x only. We passed these details to Debian https://bugs.debian.org
  /cgi-bin/bugreport.cgi?bug=964541 too.

  But I do wonder, if there is something different or incorrect about
  posix_spawn() implementation in either glibc, or linux kernel, on
  s390x. Or gnu-make's usage of posix_spawn().

  As otherise, using posix_spawn() in gnu-make works on other
  architectures, and flatpak-builder autopkgtests pass too.

  It seems very weird that stdout does not appear to be functional,
  unless stderr was opened/written to, from gnu-make execution compiled
  with posix-spawn feature.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu-z-systems/+bug/1886814/+subscriptions