Kudos to Konstantin Belousov! I'm not sure if this list was interested into all this error tracking. So we made the error tracking with private mails. Anyway, it was a BIOS setting named "limit CPUID maximum" and I had to disable it (BIOS help said "disabled for Windows XP"). Thank you Konstantin Belousov, you have an amazing skill in this low level debugging stuff. :) Sincerely yours Andre.
hi! What was that option actually doing? How'd it break things? -adrian On 27 July 2015 at 05:02, Andre Meiser <ortadur at web.de> wrote:> Kudos to Konstantin Belousov! > > I'm not sure if this list was interested into all this error tracking. So we made the error tracking with private mails. > > Anyway, it was a BIOS setting named "limit CPUID maximum" and I had to disable it (BIOS help said "disabled for Windows XP"). > > Thank you Konstantin Belousov, you have an amazing skill in this low level debugging stuff. :) > > Sincerely yours Andre. > _______________________________________________ > freebsd-stable at freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscribe at freebsd.org"
Hi, On 27 July 2015 at 22:41, Adrian Chadd wrote:> What was that option actually doing? How'd it break things?old operating systems like Windows 98 can't handle a CPUID higher than 3. But Pentium 4 with HTT (Hyper-Threading Technologie) has a higher value. So the BIOS can limit it to 3. The default value from the BIOS is set to limit the CPUID. And this caused troubles with FreeBSD which used for all but the first CPU a far bigger data structure (ucontext_t) for threads. So sometimes the stack didn't had enough space for this big structure and made a segmentation fault (see subject -> many core dumps). This become fixed by Konstantin Belousov today. So the next FreeBSD release won't be affected by this BIOS setting on P4 with HTT. Sincerely yours Andre.