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SubjectRe: Fix memory leak in swsusp
Hi!

> > > We were avoiding the use of memcpy because it messes up the preempt count with 3DNow, and
> > > potentially as other unseen side effects. The preempt could possibly simply be reset at resume time,
> > > but the point remains.
> >
> > eh? memcpy just copies memory. Maybe your meant copy_*_user()?
>
> See arch/i386/lib/memcpy.c The 3dnow routine does kernel_fpu_begin()/..end()
> which futzes with preempt count. What I'm missing though is that the count
> afterwards should be the same as it was before the memcpy. Why is this
> a problem for the suspend folks?

It does not hurt here, but as someone else explained already it is a
problem when doing atomic copy of memory. (You increment, than copy
whole memory, you decrement; but you only decrement in original, not
in copy...)
Pavel
--
People were complaining that M$ turns users into beta-testers...
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