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Date: Sun, 25 Jan 2004 14:19:25 -0800 (PST)
From: Don Lewis <truckman@FreeBSD.org>
To: mat@cnd.mcgill.ca
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cc: cg@FreeBSD.org
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Subject: Re: dev/sound/pcm/* patch testers wanted
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On 25 Jan, Mathew Kanner wrote:
> On Jan 24, Don Lewis wrote:
>> The is a buffer overflow in the interrupt handler in the vchan code that
>> occasionally stomps on something on the kernel heap and causes panics in
>> other parts of the kernel.  I tracked down the cause of the buffer
>> overflow with the help of Stefan Ehmann and made a number of changes to
>> the sound/pcm/* code to try to avoid triggering the overflow.
> 
>> [...]
> 
> 	Don,
> 	I think it should be noted that vchans aren't always enabled
> by default and those testing this patch should explicitly make sure
> that vchans are enabled either via
> 
> 	sysctl hw.snd.pcmX.vchans=5

That's a good point.  I'd also like to make sure that I didn't break
anything in the non-vchan case, so testing with vchans on and off would
be useful.