Heads up - Linux 5.2+ Hit By AVX Register Corruption Bug
Linux kernels 5.2+ contain a bug that can cause memory corruption and affects at leat Go apps.
https://www.phoronix.com/scan.php?page=news_item&px=Linux-5.2-Go-Register-Corrupt
The bug only shows if the kernel is compiled with gcc 9.
I just checked 5.3.7-x86_64-linode130 and 5.3.11-x86_64-linode131 on my Nanode, they do not seem to be affected.
Perhaps Linode kernels are compiled with gcc 8?
Anyway, just wanted to give a heads up to the Linode kernel team.
The bug is already fixed:
https://lkml.org/lkml/2019/11/27/304
but I'm not sure about merge / release status.
5 Replies
GCC 9 is very new, and not available in many distros, so Linode is not likely to run into this until long after it's fixed upstream. Notably, of the "mainstream" distros, it's only available in Ubuntu 19.04 or newer and Fedora 30 or newer. I happen to know that Linode is a fan of Debian, which does not have GCC 9 in any released version.
@kmansoft Thanks for the heads up! I have passed this information along to our kernels team so that they can review it.
@kmansoft I've just heard back from one of our system engineers. They let me know that our kernels are not compiled with GCC 9 and that we are unaffected by this bug. Thanks again!
