My system has been locking up reliably ever since I upgraded my athlon 850 to an XP 1600+. Perhaps it is this bug manifesting itself. Nothing strange shows up in the logs. What's odd though is that it was rock solid with the old Athlon. Hardware is KT133A, matrox G550, Xfree CVS from Dec., kernel 2.4.13. My first though was maybe a bios issue, but there are no new bioses available for my board. My next thought was perhaps a bug in Xfree, or the kernel, but I haven't had time to try a new xfree or kernel. Maybe today. Alex --- J Hayward <jimhayward@earthlink.net> wrote: > Hello everyone, > > I saw this on www.linuxtoday.com I thought I would > post it here. > > Quote: > "...a major Athlon CPU bug has been discovered, and > it affects Linux > 2.4. Note that this is a bug in the actual CPU > itself, and is not a > Linux bug. However, it becomes our problem because > there are very many > semi-broken Athlon/Duron/Athlon MP CPUs out there. > > Here are the details. As you may know, x86 systems > have traditionally > managed memory using 4K pages. However, with the > introduction of the > Pentium processor, Intel added a new feature called > extended paging, > which allows 4Mb pages to be used instead. Here's > the problem -- many > Athlon and Duron CPUs experience memory corruption > when extended paging > is used in conjunction with AGP. And, this problem > hits us because Linux > 2.4 kernels compiled with a Pentium-Classic or > higher Processor family > kernel configuration setting will automatically take > advantage of > extended paging (for kernel hackers out there, this > is the > X86_FEATURE_PSE constant defined in > include/asm-i386/cpufeature.h.) > Fortunately, there is a quick and easy fix for this > problem. If you have > been experiencing lockups on your Athlon, Duron or > Athlon MP system when > using AGP video, try passing the mem=nopentium > option to your kernel > (using GRUB or LILO) at boot-time. This tells Linux > to go back to using > 4K pages, avoiding this CPU bug. In addition, it > should also be possible > to avoid this problem by not using AGP on affected > systems. As soon as I > discovered that this CPU bug existed (which > happened, unfortunately, > because my CPU has the bug), I informed kernel > hacker Andrew Morton of > the issue; he put me in touch with Alan Cox. Alan is > going to try to add > some kind of Athlon/AGP CPU bug detection code to > the kernel so that it > will be able to auto-downgrade to 4K pages when > necessary." > > http://linuxtoday.com/news_story.php3?ltsn=2002-01-21-001-20-NW-KN > > Will be interesting to hear what AMD;s response to > this is. I would like > to see exactly which Athlon/Duron processors are > effected. > > Regards, > Jim H > > > ATTACHMENT part 2 application/pgp-signature name=signature.asc __________________________________________________ Do You Yahoo!? Send FREE video emails in Yahoo! Mail! http://promo.yahoo.com/videomail/
