[PATCH] Keep a shadow copy of HFA384X_INTEN_OFF

Pavel Roskin proski at gnu.org
Mon May 26 13:46:50 EDT 2003

On Mon, 26 May 2003, Denis Vlasenko wrote:

> > But why?  I'm not aware of any reason why it's bad.  Are you afraid
> > to lose one of the settings?  But each of them if written correctly,
> > and they are kept separately in the MAC chip.
> Hey hey... In my example CPU1 executes ioctl to set rate to 5M
> while CPU2 sets rate to 11M. Look at the picture again: those set_word()s
> write rate settings into two separate registers, and due to race
> one reg is set to 5, and other to 11M. This is not ok.

This can only happen if you run two instances of iwconfig in the same 
time and they both try to set different rates.  You cannot expect 
predictable results if you do it, regardless of the locks.

cannot be set.  The code already assumes that nothing fatal happens if
they are set to different values.

Maybe I don't see something obvious, but then I'm probably too
unexperienced to discuss it.  Please don't copy to me if you want to
continue this discussion.  I don't have time to discuss something I don't
understand after three iterations.  I'll rather work on something I

Pavel Roskin

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