KVM: x86: Advertise fast REP string features inherent to the CPU

mainline inclusion
from mainline-v6.3-rc1
commit 2a4209d6
category: feature
feature: SPR fast rep string operations
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I6YPV0
CVE: N/A

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2a4209d6a9cb51082813e3081e1172ae68d27935



Intel-SIG: commit 2a4209d6 ("KVM: x86: Advertise fast REP string features inherent to the CPU")

-------------------------------------

Fast zero-length REP MOVSB, fast short REP STOSB, and fast short REP
{CMPSB,SCASB} are inherent features of the processor that cannot be
hidden by the hypervisor. When these features are present on the host,
enumerate them in KVM_GET_SUPPORTED_CPUID.

Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220901211811.2883855-2-jmattson@google.com


Signed-off-by: Sean Christopherson <seanjc@google.com>
[ jason: resolve conflicts and amend commit log ]
Signed-off-by: Jason Zeng <jason.zeng@intel.com>