On 11/06/18 10:06, Ruiyu Ni wrote: > Today's code unconditionally sets the IA32_FEATURE_CONTROL.Lock to 1 > no matter the feature is enabled or not. > > The patch fixes this issue by only setting the Lock bit to 1 when > the feature is enabled. > > Contributed-under: TianoCore Contribution Agreement 1.1 > Signed-off-by: Ruiyu Ni <[email protected]> > Cc: Eric Dong <[email protected]> > Cc: Laszlo Ersek <[email protected]> > --- > UefiCpuPkg/Library/CpuCommonFeaturesLib/FeatureControl.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/UefiCpuPkg/Library/CpuCommonFeaturesLib/FeatureControl.c > b/UefiCpuPkg/Library/CpuCommonFeaturesLib/FeatureControl.c > index 8c1eb5eb4f..0b85f25f90 100644 > --- a/UefiCpuPkg/Library/CpuCommonFeaturesLib/FeatureControl.c > +++ b/UefiCpuPkg/Library/CpuCommonFeaturesLib/FeatureControl.c > @@ -1,7 +1,7 @@ > /** @file > Features in MSR_IA32_FEATURE_CONTROL register. > > - Copyright (c) 2017, Intel Corporation. All rights reserved.<BR> > + Copyright (c) 2017 - 2018, Intel Corporation. All rights reserved.<BR> > This program and the accompanying materials > are licensed and made available under the terms and conditions of the BSD > License > which accompanies this distribution. The full text of the license may be > found at > @@ -184,6 +184,14 @@ LockFeatureControlRegisterInitialize ( > { > MSR_IA32_FEATURE_CONTROL_REGISTER *MsrRegister; > > + // > + // When Lock Feature Control Register feature is disabled, > + // just skip the MSR lock bit setting. > + // > + if (!State) { > + return RETURN_SUCCESS; > + } > + > // > // The scope of Lock bit in the MSR_IA32_FEATURE_CONTROL is core for > // below processor type, only program MSR_IA32_FEATURE_CONTROL for thread > 0 in each >
I'll defer to Eric on this, as OVMF does not use this lib instance. (In fact, no platform in the edk2 tree seems to.) Thanks, Laszlo _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
