Re: frequent lockups in 3.18rc4

From: Linus Torvalds
Date: Sat Dec 20 2014 - 16:16:34 EST


On Sat, Dec 20, 2014 at 10:25 AM, Linus Torvalds
<torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> How/where is the HPET overflow case handled? I don't know the code enough.

Hmm, ok, I've re-acquainted myself with it. And I have to admit that I
can't see anything wrong. The whole "update_wall_clock" and the shadow
timekeeping state is confusing as hell, but seems fine. We'd have to
avoid update_wall_clock for a *long* time for overflows to occur.

And the overflow in 32 bits isn't that special, since the only thing
that really matters is the overflow of "cycle_now - tkr->cycle_last"
within the mask.

So I'm not seeing anything even halfway suspicious.

Linus
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