This reverts commit b0157ad73a.
```
commit b0157ad73a
Refs: 3.3.0-alpha0-124-gb0157ad73
Author: Fabiano Fidêncio <fabiano.fidencio@intel.com>
AuthorDate: Fri Aug 11 14:55:11 2023 +0200
Commit: Fabiano Fidêncio <fabiano.fidencio@intel.com>
CommitDate: Fri Nov 10 12:58:20 2023 +0100
runtime: confidential: Do not set the max_vcpu to cpu
We don't have to do this since we're relying on the
`static_sandbox_resource_mgmt` feature, which gives us the correct
amount of memory and CPUs to be allocated.
Signed-off-by: Fabiano Fidêncio <fabiano.fidencio@intel.com>
```
This commit was removing a requirement that was made previously, but due
to the SMP issue we're facing with the QEMU used for TDX (see commit
d1b54ede290e95762099fff4e0bcdad10f816126*), QEMU will fail to start due
to:
```
Invalid CPU topology: product of the hierarchy must match maxcpus:
sockets (1) * dies (1) * cores (1) * threads (1) != maxcpus (240)"
```
This has no affect on the SEV / SNP workflow and hopefully we'll be able
to re-revet this soon enough, when this gets solved on te QEMU side.
Last but not least, this is not a "clean" revert as we're using
conf.NumVCPUs() instead of conf.NumVCPUs, to ensure we're dealing with
uint32.
Fixes: #8532
Signed-off-by: Fabiano Fidêncio <fabiano.fidencio@intel.com>
This patch adds the support of the remote hypervisor type.
Shim opens a Unix domain socket specified in the config file,
and sends TTPRC requests to a external process to control
sandbox VMs.
Fixes#4482
Co-authored-by: Pradipta Banerjee <pradipta.banerjee@gmail.com>
Co-authored-by: stevenhorsman <steven@uk.ibm.com>
Signed-off-by: Yohei Ueda <yohei@jp.ibm.com>
(based on commit f9278f22c3)
First of all, this is a controversial piece, and I know that.
In this commit we're trying to make a less greedy approach regards the
amount of vCPUs we allocate for the VMM, which will be advantageous
mainly when using the `static_sandbox_resource_mgmt` feature, which is
used by the confidential guests.
The current approach we have basically does:
* Gets the amount of vCPUs set in the config (an integer)
* Gets the amount of vCPUs set as limit (an integer)
* Sum those up
* Starts / Updates the VMM to use that total amount of vCPUs
The fact we're dealing with integers is logical, as we cannot request
500m vCPUs to the VMMs. However, it leads us to, in several cases, be
wasting one vCPU.
Let's take the example that we know the VMM requires 500m vCPUs to be
running, and the workload sets 250m vCPUs as a resource limit.
In that case, we'd do:
* Gets the amount of vCPUs set in the config: 1
* Gets the amount of vCPUs set as limit: ceil(0.25)
* 1 + ceil(0.25) = 1 + 1 = 2 vCPUs
* Starts / Updates the VMM to use 2 vCPUs
With the logic changed here, what we're doing is considering everything
as float till just before we start / update the VMM. So, the flow
describe above would be:
* Gets the amount of vCPUs set in the config: 0.5
* Gets the amount of vCPUs set as limit: 0.25
* ceil(0.5 + 0.25) = 1 vCPUs
* Starts / Updates the VMM to use 1 vCPUs
In the way I've written this patch we introduce zero regressions, as
the default values set are still the same, and those will only be
changed for the TEE use cases (although I can see firecracker, or any
other user of `static_sandbox_resource_mgmt=true` taking advantage of
this).
There's, though, an implicit assumption in this patch that we'd need to
make explicit, and that's that the default_vcpus / default_memory is the
amount of vcpus / memory required by the VMM, and absolutely nothing
else. Also, the amount set there should be reflected in the
podOverhead for the specific runtime class.
One other possible approach, which I am not that much in favour of
taking as I think it's **less clear**, is that we could actually get the
podOverhead amount, subtract it from the default_vcpus (treating the
result as a float), then sum up what the user set as limit (as a float),
and finally ceil the result. It could work, but IMHO this is **less
clear**, and **less explicit** on what we're actually doing, and how the
default_vcpus / default_memory should be used.
Fixes: #6909
Signed-off-by: Fabiano Fidêncio <fabiano.fidencio@intel.com>
Signed-off-by: Christophe de Dinechin <dinechin@redhat.com>
We don't have to do this since we're relying on the
`static_sandbox_resource_mgmt` feature, which gives us the correct
amount of memory and CPUs to be allocated.
Signed-off-by: Fabiano Fidêncio <fabiano.fidencio@intel.com>
Ideally this config validation would be in a seperate package
(katautils?), but that would introduce circular dependency since we'd
call it from vc, and it depends on vc types (which, shouldn't be vc, but
probably a hypervisor package instead).
Signed-off-by: Eric Ernst <eric_ernst@apple.com>