The workaround for XSA-433 (Zenbleed, CVE-2023-20593) was later re-worked to better integrate...

The workaround for XSA-433 (Zenbleed, CVE-2023-20593) was later re-worked to better integrate with other manipulations of the same MSR. In this rework an inverted conditional was introduced, resulting in the workaround to not be applied when needed and vice versa.

For more details, see: http://xenbits.xen.org/xsa/advisory-433.html