Re: [Libunwind-devel] UNW_EINVAL stepping past _L_lock_686 in pthread_mutex_lock

[Arun Sharma]

On Sun, Sep 21, 2014 at 8:34 PM, Jared Cantwell
<address@hidden> wrote:
> I've turned off address space randomization and looked for an IP in
> the vdso range.
>
> address@hidden:~/unwindrepro$ ldd a.out
> linux-gate.so.1 =>  (0xb7fff000)   <----- vdso range
> libpthread.so.0 => /lib/i386-linux-gnu/libpthread.so.0 (0xb7fcf000)
> .......
>
> Running with UNW_DEBUG_LEVEL=16 shows the following for the final
> failing unw_step call.  It doesn't look like the IP is in the vdso
> range, but I could be misreading.  To me though, it looks like the IP
> falls into libpthread, which the debug output appears to correctly
> show.
>
[..]
> Am I reading this properly, or is this actually the vdso problem?
>

Yeah - looks like a libpthread problem. readelf -wf should help you
get to the code in libpthread which is missing the unwind info. Please
check if it's fixed in glibc HEAD.

 -Arun