On 9/9/2025 5:39 PM, Chao Gao wrote:
From: Yang Weijiang <weijiang.yang@xxxxxxxxx>
Enable KVM_{G,S}ET_ONE_REG uAPIs so that userspace can access MSRs and
other non-MSR registers through them.
This is in preparation for allowing userspace to read/write the guest SSP
register, which is needed for the upcoming CET virtualization support.
Currently, two types of registers are supported: KVM_X86_REG_TYPE_MSR and
KVM_X86_REG_TYPE_KVM. All MSRs are in the former type; the latter type is
added for registers that lack existing KVM uAPIs to access them. The "KVM"
in the name is intended to be vague to give KVM flexibility to include
other potential registers. We considered some specific names, like
"SYNTHETIC" and "SYNTHETIC_MSR" before, but both are confusing and may put
KVM itself into a corner.
Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Signed-off-by: Yang Weijiang <weijiang.yang@xxxxxxxxx>
Link: https://lore.kernel.org/all/20240219074733.122080-18-weijiang.yang@xxxxxxxxx/ [1]
Tested-by: Mathias Krause <minipli@xxxxxxxxxxxxxx>
Tested-by: John Allen <john.allen@xxxxxxx>
Tested-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
Signed-off-by: Chao Gao <chao.gao@xxxxxxxxx>
Reviewed-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
