Re: [PATCH v3 03/25] x86/sgx: Wipe out EREMOVE from sgx_free_epc_page()

Paolo Bonzini
2021-03-23T16:39:42Z

On 23/03/21 17:06, Borislav Petkov wrote:
>> Practically speaking, "basic" deployments of SGX VMs will be insulated from
>> this bug. KVM doesn't support EPC oversubscription, so even if all EPC is
>> exhausted, new VMs will fail to launch, but existing VMs will continue to chug
>> along with no ill effects....
>
> Ok, so it sounds to me like*at* *least* there should be some writeup in
> Documentation/ explaining to the user what to do when she sees such an
> EREMOVE failure, perhaps the gist of this thread and then possibly the
> error message should point to that doc.

That's important, but it's even more important *to developers* that the
commit message spells out why this would be a kernel bug more often than
not. I for one do not understand it, and I suspect I'm not alone.

Maybe (optimistically) once we see that explanation we decide that the
documentation is not important. Sean, Kai, can you explain it?

Paolo