On 10/23/06 8:31 PM, "Thor Lancelot Simon" <tls@rek.tjls.com> wrote:

> On Mon, Oct 23, 2006 at 07:59:40PM -0500, John Darrow wrote:
...
>> The included patch seems to be handling things for us (we haven't
>> seen crashes or hangs since it was put in place).
>> 
>> --- /current/src/sys/dev/pci/if_pcn.c_v1.32    2006-10-16 19:28:36.000000000
>> -0500
>> +++ /current/src/sys/dev/pci/if_pcn.c    2006-10-18 02:17:04.000000000 -0500
>> @@ -126,7 +126,11 @@
>>   * DMA segments, but only allocate the max of 512 descriptors.  The
>>   * transmit logic can deal with this, we just are hoping to sneak by.
>>   */
>> +#ifdef PCN_VMWARE_SGLIMIT
>> +#define    PCN_NTXSEGS        4
> 
> I think you want "15" here, not "4".  More is better, and according to
> the information above, 15 should be safe, no?
> 
> It's bogus for the thing to claim to be a pcnet if it in fact is not
> quite a pcnet, and since the number of supported s/g elements is a
> documented in the pcnet and ilacc databooks... sigh.
> 
> If you don't want to patch your kernel, it might be possible to run the
> thing in 24-bit-descriptor mode instead by removing pcn from your kernel
> so it matches le@pci.  I wonder if that will show the same Vmware bug?
> 

I have no problem building/running without pcn -- that is an easy test to
run.

Aside from anecdotal experiences, is there a sure-fire way to trip over this
and aid with testing?

peter