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Re: options RND_COM considered dangeous



On Sat, Nov 15, 2008 at 04:10:34PM -0500, Rafal Boni wrote:
> I just got a locking-against-myself panic on an XScale pxa250 (ARM)
> [..]
> 
> It looks like the problem is that the callout data is protected by locks
> at IPL_SCHED whereas com(4) interrupts at IPL_HIGH; the lock that is being
> locked recursively is the callout lock.
> 
> I don't know if there are serial drivers that run at-or-below-IPL_SCHED,
> but if not, it might make sense to remove the RND_COM option.

It's been marked broken in i386 configs for exactly this reason;
apparently the same applies elsewhere.  

--
Dan.

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