Re: [PATCH] x86/EPT: squash meaningless TLB flush

[Andrew Cooper <amc96@xxxxxxxx>]

On 30/11/2021 16:10, Jan Beulich wrote:
> ept_free_entry() gets called after a flush - if one is necessary in the
> first place - was already issued. That behavior is similar to NPT, which
> also doesn't have any further flush in p2m_free_entry(). (Furthermore,
> the function being recursive, in case of recursiveness way too many
> flushes would have been issued.)
>
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

ept_free_entry() is called either recursively, or after an
ept_split_super_page(), and I agree that it does not want to queue
multiple flushes.

However, I don't see where a suitable flush is in the superpage path. 
Am I overlooking something?

~Andrew