Messages in this thread | | | Date | Mon, 28 Feb 2022 16:10:36 +0000 | From | Sean Christopherson <> | Subject | Re: [PATCH] kvm: x86: Adjust the location of pkru_mask of kvm_mmu to reduce memory |
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On Mon, Feb 28, 2022, Peng Hao wrote: > From: Peng Hao <flyingpeng@tencent.com> > > Adjust the field pkru_mask to the back of direct_map to make up 8-byte > alignment.This reduces the size of kvm_mmu by 8 bytes.
I'd prefer we just burn the extra 8 bytes, at least for now. 'prku' and 'permissions' are related fields, IMO splitting them to save 24 bytes per vCPU isn't a good tradeoff.
And in the not-too-distant future, all of the 1-byte fields will hopefully go away, at which point were "wasting" 4 bytes no matter where 'pkru' is defined. 'ept_ad' can be dropped immediately, I'll send a patch for that. We should be able to drop 'root_level', 'shadow_root_level', and 'direct_map' once Paolo's clean up of the role stuff lands.
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