On Sun, Jun 15, 2014 at 08:56:17PM +0200, Mark Wielaard wrote:
On Sun, 2014-06-15 at 20:47 +0200, Kurt Roeckx wrote:
> On Sun, Jun 15, 2014 at 08:38:20PM +0200, Mark Wielaard wrote:
> >
> > Since the sparc backend doesn't have unwinder support it sounds unlikely
> > one of these patches triggered the bus error. Do you have more
> > specifics? Which test triggers it, do you have a backtrace? Are there
> > logs before/after, etc.
>
> Log before:
>
https://buildd.debian.org/status/fetch.php?pkg=elfutils&arch=sparc&am...
>
> Log after:
>
https://buildd.debian.org/status/fetch.php?pkg=elfutils&arch=sparc&am...
Strange indeed. But I am afraid you'll have to run one of the failing
tests under GDB to help debug it. At least so we know where it is
crashing and if it is crashing in elfutils code or somewhere else (using
completely different gcc and glibc versions before/after is slightly
suspicious, even though it might still be a bug in our code of course).
Program terminated with signal SIGBUS, Bus error.
b#0 core_set_initial_registers (thread=0xffef2018, thread_arg_voidp=<optimized
out>) at linux-core-attach.c:299
299 uint64_t val64 = *(const uint64_t *) reg_desc;
(gdb) bt
#0 core_set_initial_registers (thread=0xffef2018, thread_arg_voidp=<optimized out>)
at linux-core-attach.c:299
#1 0xf79f43cc in dwfl_thread_getframes (thread=thread@entry=0xffef2018,
callback=callback@entry=0x12520 <frame_callback>, arg=arg@entry=0xffef2088) at
dwfl_frame.c:402
#2 0x00012ba8 in thread_callback (thread=0xffef2018, thread_arg=0xffef2088) at
stack.c:458
#3 0xf79f41e0 in dwfl_getthreads (dwfl=0x28358, callback=callback@entry=0x12b80
<thread_callback>, arg=arg@entry=0xffef2088) at dwfl_frame.c:270
#4 0x0001150c in main (argc=8, argv=0xffef2354) at stack.c:731
Dropping the patches doesn't have any effect on the result.
Note that this is a 32 bit userland sparc, but the kernel is 64 bit.
I'm not sure what that code is doing there. But it seems to be
looking at a 64 bit core file (x86_64, arm64, s390x) and then
create a 64 bit pointer is trying to dereference that.
Kurt