On Tue, Mar 16, 2021 at 04:18:42PM +0000, Andrew Cooper wrote: > In hindsight, this was a poor move. Some of these MSRs require probing for, > causing unhelpful spew into xl dmesg, as well as spew from unit tests > explicitly checking behaviour. > > This restores behaviour close to that of Xen 4.14.
I think it might be worth adding that guest access to those MSRs will now always trigger a #GP, even when msr_relaxed is used. This is however fine, as that's not a regression when compared to older Xen versions, where access to the MSRs also trigger a #GP unconditionally. I assume the wrmsr side is added so that when using msr_relaxed Xen also injects a #GP for writes to those MSRs, as it would do for reads? Thanks, Roger.
