init segfaults when compiled with glibc

On Tue, Mar 30, 2010 at 7:58 PM, Yann E. MORIN
<[email protected]> wrote:

Sasha, All,

On Tuesday 30 March 2010 16:26:14 Sasha Sirotkin wrote:
> On Tue, Mar 30, 2010 at 4:20 PM, Yann E. MORIN > <yann.morin.1998 at anciens.enib.fr
<mailto:[email protected]>> wrote:
> On Tuesday 30 March 2010 142701 Sasha Sirotkin wrote:
> > I compiled an external toolchain with glibc support using
> crosstools-ng
> > as recommended. I managed to compile buildroot without any
issues.
> > However, when I try to use the resulting image /sbin/init
segfaults.

Standard init, or busybox' ?

> > With uclibc there are no such issues. I'm using the latest
> versions of
> > everything on ARM with EABI.

In crosstool-NG, there's a sample that is quite up-to-date and that builds
an arm-unknown-linux-gnueabi:
# ct-ng show-arm-unknown-linux-gnueabi arm-unknown-linux-gnueabi [l ]
OS : linux-2.6.31.12
Companion libs : gmp-4.3.1 mpfr-2.4.2 libelf-0.8.12
binutils : binutils-2.19.1
C compiler : gcc-4.3.2 (C,C++,Fortran,Java)
C library : glibc-2.9
Tools : sstrip dmalloc-5.5.2 duma-2_5_15 gdb-6.8
ltrace-0.5.3 strace-4.5.19

> By default, gcc will emit armv5t instructions. What's your
target CPU?
> init segfaulting can be a symptom of using a bad instruction
set, so if
> your CPU is armv4, and you did not tell gcc to default to
armv4, then
> you will hit this segfault issue.
> As I already mentioned, it works fine with uClibc, so it is
definitely
> not a CPU instructions issue. At any rate, my CPU is AT91, i.e.
armvte
> instruction set.

Ahem. Right, sorry.

I'll read you back on crossgcc... :-)

It happens with both busybox and standard init.

Compilation of crossgcc with EABI work OK, but than I got this segmentation fault issue...

It looks like glibc does not work at all with buildroot right now. Should I open a bug ticket or something?

Hi Sasha,

Unfortunately, without more details, a bug report would be fairly useless. Can you send your Buildroot .config and kernel .config so that I can try to reproduce your problem on my AT91 systems ?

Thanks,

Thomas

Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com