Re: BUG: Global FPU corruption in 2.2

[Michal Jaegermann]

On Tue, Apr 24, 2001 at 06:56:32PM +0200, Christian Ehrhardt wrote:
> On Tue, Apr 24, 2001 at 09:10:07AM -0700, Linus Torvalds wrote:
> > ptrace only operates on processes that are stopped. So there are no
> > locking issues - we've synchronized on a much higher level than a
> > spinlock or semaphore.
> 
> This is only true for requests other than PTRACE_ATTACH and
> PTRACE_ATTACH is exactly what I'm worried about.

May I remind everybody that at the beginning of this thread I posted
another example, from an SMP Alpha, of FPU problems.  It certainly
was not exactly like the one under discussion but it looked that
it had a similar "smell" to it.

It looks like that to reproduce this Alpha example one needs processors
with a rather fast clock and this hardware version is not yet very
widely available.

  Michal