Dear FreeBSD Developers:

I used the ZFS Guru LiveCD to install FreeBSD 9 in KVM on a host system
with an AMD Thuban processor (K10h). I then proceeded to compile perl
and the VM crashed. Linux's dmesg gave me the following hint as to the
cause:

[ 3568.234654] KVM: Guest triggered AMD Erratum 383

I also tried installing Gentoo Prefix, a userland package manager like
NetBSD pkgsrc, and the VM also crashed with the same message when
compiling the first component. AMD has documented this issue, with a
workaround for hypervisors and a statement saying that they won't fix it:

"If system software performs uncommon methods to change the page size of
an active page table that is valid, the CPU core may, under a highly
specific and detailed set of conditions, form duplicate TLB entries for
a single linear address. The CPU core will machine check if this page is
then accessed prior to it being invalidated from the TLB."

http://support.amd.com/us/Embedded_TechDocs/41322.pdf

Has anyone done anything to workaround this issue? I have a Gentoo
Hardened VM running on this machine which has no problem compiling
software, so I am sure that some sort of page table workaround is possible.

Yours truly,
Richard Yao

Attachment: signature.asc
Description: OpenPGP digital signature

Reply via email to