On Sat, 24 Jan 2004, Luigi Rizzo wrote: > On Sat, Jan 24, 2004 at 02:12:12PM -0500, Robert Watson wrote: > ... > > > but going this way you have no idea on what the driver does, including > > > enabling hw checksums. This looks like a useless test at least for the > > > purpose of finding out what is going wrong > > > > Actually, I'm more curious about whether it's a known errata/misbehavior > > for the card that 3Com's drivers work around, or not. The problem could > > well be compleely unrelated to hardware checksuming per se -- the > > corruption might well be taking place as the buffer is moved from the > > card's buffer to the operating system managed buffer. If the NDIS driver > > doesn't illustrate the same problem, it tells us that by frobbing > > appropriately, this problem can be worked around. It also tells us that > > by looking a bit harder at what the driver is doing (i.e., how it frobs > > the hardware), we can learn something about the appropriate workaround. > > yes, but how would you know that, short of reverse engineering the > driver, or tracing I/O accesses to the hardware ? It really looks like > an overkill effort... I'd rather just try to debug the issue working on > an open source driver, or dump the hardware altogether and replace it > with something known to work...
My understanding is that NDIS drivers rely on the HAL provided by NT to perform hardware access, so you can generate I/O traces with relative ease. Decoding and following the HAL traces during card setup is probably relatively straight forward, since presumably most of the I/O transactions will match the documented services of the card. It might be useful to add some KTR support to Bill's NDIS pieces for this very purpose, if there's interest. Robert N M Watson FreeBSD Core Team, TrustedBSD Projects [EMAIL PROTECTED] Senior Research Scientist, McAfee Research _______________________________________________ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]"
