Messages in this thread | | | Date | Mon, 05 Apr 2010 12:22:33 -0700 (PDT) | Subject | Re: Random scheduler/unaligned accesses crashes with perf lock events on sparc 64 | From | David Miller <> |
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From: Frederic Weisbecker <fweisbec@gmail.com> Date: Mon, 5 Apr 2010 08:57:04 +0200
> It seems to happen after an unaligned access fixup.
You shouldn't be getting the unaligned fixup in the first place, especially in the locations where you see them. I suspect that once you see first fixup, all of the registers in the cpu have been corrupted in one way or another.
I suspect something fundamental gets corrupted, for example the current register window (%cwp) is corrupted and that screws up all of the registers so every single function starts accessing garbage.
My suspicions lie in three places, the ftrace mcount() stubs, stack_trace_flush(), or the new perf_arch_save_caller_regs() since those are the three places offhand that could make us potentially make us return to function in the wrong register window.
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