Re: [PATCH] netpoll: Fix carrier detection for drivers that are using phylib

Matt Mackall
2009-07-09T12:58:03Z

On Thu, 2009-07-09 at 09:56 +0200, Peter Zijlstra wrote:
> On Wed, 2009-07-08 at 17:01 -0700, Linus Torvalds wrote:
> > Looking at the people looking at SYSTEM_RUNNING, I do note some odd cases.
> > Why the heck does kernel/perf_counter.c do it, for example?
>
> Ah, those are the swcounter and other probe entry points. I've had
> several cases where we called into the perf counter code from those
> points before it was initialized, getting in kernel segfaults due to
> dereferencing uninitialized data etc..
>
> I could keep a variable that tracked the perf_counter_init() state, and
> use that instead if you prefer?

Looks like that'd be more accurate. Linus's proposed patch might break
your current assumptions.

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