Date: Sun, 24 Nov 1996 13:55:54 -0800 From: David Greenman <dg@root.com> To: Kent Vander Velden <graphix@iastate.edu> Cc: Tom Samplonius <tom@sdf.com>, hackers@freefall.freebsd.org Subject: Re: ping and freebsd crashes Message-ID: <199611242155.NAA05204@root.com> In-Reply-To: Your message of "Sun, 24 Nov 1996 13:52:10 CST." <9611241952.AA18700@spiff.cc.iastate.edu>
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>>> > How much memory does the test machine have in it? >>> >>> 20M and used for very little. There is not really a load on it. >> >> Are you using a non-GENERIC kernel? If so, do you have BOUNCE_BUFFERS >>compiled in? If so, this is your problem. Apparently the lance ethernet >>cards use DMA, and if you have more than 16MB and no bounce buffers, the >>card could be overwriting all kinds of thing in main memory, including >>file buffers (which would explain disk corruption). >> > > Is a non-generic kernel it is one that has been customized then, yes I >am using a non-generic kernel. It does have BOUNCE_BUFFERS enabled >which I did to use the 20M and the 1542 in the machine. > > I am confused by your statement above. You seem to say that if >BOUNCE_BUFFERS are enabled then this is a problem but describe a problem >that happens when they are not enabled. Should I get a different >ethernet card, remove memory or does someone have another suggestion? The lance driver does not support bounce buffers. If it should for some reason allocate memory above 16MB, you will lose. It's very likely that this is the cause of your problems. The reason that it is tickled by promiscuous mode is because the received traffic is much higher and uses more buffers. -DG David Greenman Core-team/Principal Architect, The FreeBSD Project
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