On 29/06/14 20:44, Borislav Petkov wrote:
This then is an old(er) version of GCC issue (but I dunno what).Right, so the error points at __spin_lock_mb_cache_entry(struct mb_cache_entry *ce) { spin_lock(bgl_lock_ptr(mb_cache_bg_lock, <--- (hash_64((unsigned long)ce, __builtin_log2(8))))); } somewhere here and I'd guess that old gcc is issuing some lib function which uses SSE. And after we disabled all FPU stuff in the kernel with b399fe355b30 ("x86: Disable generation of traditional x87 instructions") that would issue such an error. And I was about to point at that __builtin_log2 thing which looked suspicious and found this by chance: http://lkml.kernel.org/r/[email protected] You could test this patch with that old gcc 4.2.x as it looks like a good candidate for a fix for your issue.
Thanks Boris, but unfortunately I had to trash GCC 4.2.4 to build the new 4.7.4 version - so I can't test the patch :(
At least this issue is now on record so others will not need to go to penalties.
Many thanks, Nick -- "A bug in the code is worth two in the documentation." FSF Associate Member 5508 http://linicks.net/ http://pi.linicks.net/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
