Enable all host supported processor features for guests #300
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anirudhrb
requested review from
NunoDasNeves,
gamora12,
liuw,
praveen-pk,
russell-islam and
skinsbursky
as code owners
Move make_default_partition_create_arg into struct Mshv in preparation for the next patch that utilizes the hypercall IOCTL in constructing the create partition argument. Keep the global function as-is but mark it deprecated. Signed-off-by: Anirudh Rayabharam <anrayabh@microsoft.com>
Do a self-query of HvPartitionPropertyProcessorFeatures to determine which features are supported on the host and present the same feature set to guests by default. As before, VMM can override these features if needed. This approach is more robust than the previous approach where we were handpicking features to enable (on arm64) or blindly enabling all features (in x86). Signed-off-by: Anirudh Rayabharam <anrayabh@microsoft.com>
Fix the following warnings:
warning: unused import: `ioctl_with_ref`
--> mshv-ioctls/src/ioctls/vcpu.rs:15:47
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15 | use vmm_sys_util::ioctl::{ioctl_with_mut_ref, ioctl_with_ref};
| ^^^^^^^^^^^^^^
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warning: unused import: `std::mem`
--> mshv-ioctls/src/ioctls/vm.rs:868:9
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868 | use std::mem;
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Signed-off-by: Anirudh Rayabharam <anrayabh@microsoft.com>
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| ) | ||
| .unwrap(); | ||
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| create_args.pt_cpu_fbanks[0] = !host_proc_features0; |
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For better understanding - why are these are inverted? Perhaps would be worth commenting. Thanks
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Oh right, I'll add a comment. It is inverted because in create_args we need to pass the disabled processor features i.e. if bit is 1 feature is disabled and 0 is enabled.
| #[cfg(target_arch = "x86_64")] | ||
| // SAFETY: access union fields | ||
| unsafe { | ||
| let mut disabled_xsave_features = hv_partition_processor_xsave_features::default(); |
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Shouldn't this query the xsave features similarly as it's done below for states? Thanks
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I didn't do it because I don't know what the implications would be. And below it looks like we're enabling a very selected set of features. @russell-islam what do you think?
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I am not sure about the mapping between processor features and xsave.
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Summary of the PR
Query host partition processor features (using a self-query) and provide the same feature set to guests during creation. As before, the VMM is still able to override any of these flags.
This approach is more robust than the previous approach where we were handpicking features to enable (on arm64) or blindly enabling all features (in x86).
Additionally, there is also a commit in this PR to fix some build warnings on arm64.
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test.
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