Vince, I think I figured out what the bug is, can you test the following patch? If we set %g5 with the fault address here, we have to set %g4 too. This allows to correctly handle a DTLB-PROT trap for a window spill during trap entry for another top-level fault. The non-Niagara DTLB-PROT code does this properly, it's just the sun4v side that had the bug.
Great news! This fixes things. The gcc snapshot has been compiling now for over an hour without a problem, wheras before the bug would appear within seconds.
Thanks for fixing this, Vince - To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html