Date: Thu, 31 Jan 2002 18:21:12 -0800 From: Peter Wemm <peter@wemm.org> To: Kenneth Culver <culverk@yumyumyum.org> Cc: "Cameron, Frank" <Cameron@ctc.com>, Terry Lambert <tlambert2@mindspring.com>, David Malone <dwmalone@maths.tcd.ie>, "'freebsd-bugs@freebsd.org'" <freebsd-bugs@FreeBSD.ORG>, "'freebsd-current@freebsd.org'" <freebsd-current@FreeBSD.ORG> Subject: Re: AMD AGP Bug Message-ID: <20020201022112.227833809@overcee.wemm.org> In-Reply-To: <20020131135127.V22577-100000@alpha.yumyumyum.org>
next in thread | previous in thread | raw e-mail | index | archive | help
Kenneth Culver wrote: > Yeah, that's what I saw on linux-kernel... > > Ken We need to use the PAT cpu_features feature. This gives us 8 page attribute modes instead of simple no-cache / writethrough flags. We can (and must) control more carefully the speculative hardware prefetch, for example. I've been thinking about this with the pmap revamp that I'm working on. It may solve the athlon problems too. > On Thu, 31 Jan 2002, Cameron, Frank wrote: > > > From what was posted on the linux-kernel list the problem is the OS > > doing the wrong thing not the hardware. I originally asked the > > question (albeit not worded as clearly as I should have) because if > > Microsoft and Linux programmers made the same mistake, might > > FreeBSD have also. > > > > > -----Original Message----- > > > From: Kenneth Culver [mailto:culverk@yumyumyum.org] > > > Sent: Thursday, January 31, 2002 10:42 AM > > > To: Terry Lambert > > > Cc: David Malone; Cameron, Frank; 'freebsd-bugs@freebsd.org'; > > > 'freebsd-current@freebsd.org' > > > Subject: Re: AMD AGP Bug > > > > > > > > > > There's actually a seperate TLB bug, but FreeBSD doesn't > > > > trigger that one, either (Linux can tickle it, when there > > > > are certain specific circumstances met). > > > > > > > Well, I think I know what you're talking about, linux > > > allocates agpgart > > > memory without setting a "non-cacheable" bit, and then the > > > agp card writes > > > to that memory, but the cpu cached it already, which makes > > > the cache wrong > > > or something like that, and causes the crashes/hangs. I know this is a > > > greatly simplified version of the real problem, but I think this is a > > > linux bug not necesarily an amd bug. > > > > > > Ken > > > > > > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-bugs" in the body of the message > Cheers, -Peter -- Peter Wemm - peter@FreeBSD.org; peter@yahoo-inc.com; peter@netplex.com.au "All of this is for nothing if we don't go to the stars" - JMS/B5 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20020201022112.227833809>