syscall: s390x: fork/exec function not implemented

[becks]

1. What version of Go are you using (go version)?
   go version go1.7beta1 linux/amd64
2. What operating system and processor architecture are you using (go env)?
   GOARCH="s390x"
   GOHOSTARCH="amd64"
   GOHOSTOS="linux"
   GOOS="linux"
   CC="gcc"
   GOGCCFLAGS="-fPIC -m64 -march=z196 -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build929527714=/tmp/go-build"
   CXX="g++"
   CGO_ENABLED="0"
3. What did you do?
   https://play.golang.org/p/DaEDa0AMTZ

$ export GOARCH=s390x
$ go install

$ file $GOPATH/bin/linux_s390x/test
/go//bin/linux_s390x/test: ELF 64-bit MSB executable, IBM S/390, version 1 (SYSV), statically linked, not stripped

1. What did you see instead?

$ uname -a
Linux myhost 2.6.18-274.el5 #1 SMP Fri Jul 8 17:47:13 EDT 2011 s390x s390x s390x GNU/Linux

$ ./test
fork/exec /bin/ls: function not implemented

$ strace -s8192 -f ./test
[pid 19931] setup() = -1 ENOSYS (Function not implemented)
[pid 19931] setup() = -1 ENOSYS (Function not implemented)
[pid 19931] close(0) = 0
[pid 19931] close(0) = -1 EBADF (Bad file descriptor)
[pid 19931] write(2, "fork/exec /bin/ls: function not implemented", 43fork/exec /bin/ls: function not implemented) = 43

Thanks!

[ianlancetaylor]

CC @mundaym

[billotosyr]

I've not been able to reproduce this, but I have GOHOSTARCH=s390x.

[mundaym]

The program works on both RHEL 6 (2.6.32-504.23.4.el6.s390x) and 7 (3.10.0-327.4.5.el7.s390x). I assume this is therefore a RHEL 5 specific issue (I don't have a RHEL 5 machine on hand to try unfortunately). I'll investigate further tomorrow however RHEL 5 isn't supported by Go so I'm not sure we will be able to fix this (see https://golang.org/doc/install and http://dave.cheney.net/2013/06/18/how-to-install-go-1-1-on-centos-5).

[mikioh]

$ uname -a
Linux myhost 2.6.18-274.el5 #1 SMP Fri Jul 8 17:47:13 EDT 2011 s390x s390x s390x GNU/Linux

According to https://golang.org/doc/install#requirements, Go on Linux requires kernel 2.6.23 and above.

[becks]

I can confirm it works on rhel6-s390x, while it doesn't work on rhel5-s390x

[ianlancetaylor]

Closing because we don't support kernels that old. In general we don't support RHEL5. Sorry.