On 23/04/2015 13:51, Marcelo Tosatti wrote: >>> > > https://bugzilla.redhat.com/show_bug.cgi?id=1174664 >> > >> > That was the missing volatile in an asm. Older compilers didn't catch >> > it. :( > How do you know that? It looks like memory corruption (look at the > pattern at the end).
I suspect some kind of operator error there, it makes no sense. On the other hand, bug 1178975 is much clearer and the symptoms are the same. In that bug, you can see that the same kernel source works on f20 (package version 3.17.7-200.fc20.x86_64) and fails on f21 (package version 3.17.7-300.fc21.x86_64). Of course the compiler is different. The newer one hoists the lsl out of the loop; if you get a CPU migration at the wrong time, the cpu != cpu1 condition will always be true the loop will never exit. Paolo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/