Ubuntu
eglibc package

  1. Bug #956051
  2. Comment #4

Comment 4 for bug 956051

Revision history for this message
jwestfall (jwestfall) wrote :

Hi

It appears this issue can be worked around by adding the following options to xen's command line in grub.

cpuid_mask_ext_ecx=0xFFFEFFF cpuid_mask_ecx=0xEFFFFFF

This masks both FMA4 and AVX from cpuid for dom0 and all domU's

Also note that xen has a cpuid option for domU configs that allows to you mask these as well, but it doesn't seem to work for userspace making direct cpuid calls. The kernel will see that fma4 isn't there, but glibc still see's it as available and you get crashes.

jim