On 17/05/2024 10:38 am, Edgecombe, Rick P wrote:
On Fri, 2024-05-17 at 10:23 +1200, Huang, Kai wrote:
On 17/05/2024 9:46 am, Edgecombe, Rick P wrote:
On Tue, 2024-05-14 at 17:59 -0700, Rick Edgecombe wrote:
For lack of a better method currently, use kvm_gfn_shared_mask() to
determine if private memory cannot be zapped (as in TDX, the only VM type
that sets it).
Trying to replace kvm_gfn_shared_mask() with something appropriate, I saw
that
SNP actually uses this function:
https://lore.kernel.org/kvm/20240501085210.2213060-12-michael.roth@xxxxxxx/
So trying to have a helper that says "The VM can't zap and refault in memory
at
will" won't cut it. I guess there would have to be some more specific. I'm
thinking to just drop this patch instead.
Or KVM_BUG_ON() in the callers by explicitly checking VM type being TDX
as I mentioned before.
Having such checking in a generic function like this is just dangerous
and not flexible.
Just my 2 cents, though.
As I said before, the point is to catch new callers. I see how it's a little
wrong to assume the intentions of the callers, but I don't see how it's
dangerous. Can you explain?
Dangerous means when "a little wrong to assume the intentions of the
callers" actually goes wrong. In other words, a general intention to
"catch new callers" doesn't make a lot sense to me.
Anyway as said before, it's just my 2 cents, and it's totally up to you.
