Comment 3 for bug 494831

Revision history for this message
Dave Martin (dave-martin-arm) wrote :

See this bug for details of our current understanding on these SIGILLs:

https://bugs.launchpad.net/ubuntu/+source/squashfs/+bug/494667

What is the kernel version currently in use on the Marvell boards? If it's already 2.6.31 I would not expect to be having this problem— the imx51 buildds exhibit it because they're running on a 2.6.28 kernel.

If unaligned pointer use can be eliminated from the affected packages easily, it might be worth doing. (For squashfs-tools, it looks difficult and would require a lot of rewriting.)

To sanity-check whether our understanding of the problem is correct, can you:
  a) run under gdb, then when you get a SIGILL, do x/i $pc-2 (I would expect a ldm/stm/ldrd/strd instruction to have caused the fault)
  b) build the affected packages with -marm and see if the problem goes away? If not, something different may be going on...

In any case, we need to patch the kernel if is has some missing alignment fixup support after all, since we can't guarantee to fix all packages not to play fast and loose with unaligned pointers...