Naito: The fix is correct. Reviewed-by: Liming Gao <gaolim...@byosoft.com.cn>
Thanks Liming > -----邮件原件----- > 发件人: devel@edk2.groups.io <devel@edk2.groups.io> 代表 Takuto Naito > 发送时间: 2021年4月12日 23:07 > 收件人: devel@edk2.groups.io > 抄送: Takuto Naito <nait...@gmail.com>; Michael D Kinney > <michael.d.kin...@intel.com>; Liming Gao <gaolim...@byosoft.com.cn>; > Zhiguang Liu <zhiguang....@intel.com> > 主题: [edk2-devel] [PATCH v1 1/1] Fix AsmReadMsr64() and AsmWriteMsr64() > with GCC toolchain > > REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3325 > > 1. AsmReadMsr64() in X64/GccInlinePriv.c > AsmReadMsr64 can return uninitialized value if FilterBeforeMsrRead > returns False. This causes build error with the CLANG toolchain. > > 2. AsmWriteMsr64() in X64/GccInlinePriv.c > In the case that FilterBeforeMsrWrite changes Value and returns True, > The original Value, not the changed Value, is written to the MSR. > This behavior is different from the one of AsmWriteMsr64() in > X64/WriteMsr64.c for the MSFT toolchain. > > Signed-off-by: Takuto Naito <nait...@gmail.com> > Cc: Michael D Kinney <michael.d.kin...@intel.com> > Cc: Liming Gao <gaolim...@byosoft.com.cn> > Cc: Zhiguang Liu <zhiguang....@intel.com> > --- > MdePkg/Library/BaseLib/X64/GccInlinePriv.c | 7 +++---- > 1 file changed, 3 insertions(+), 4 deletions(-) > > diff --git a/MdePkg/Library/BaseLib/X64/GccInlinePriv.c > b/MdePkg/Library/BaseLib/X64/GccInlinePriv.c > index e4920f2116..244bd62ee6 100644 > --- a/MdePkg/Library/BaseLib/X64/GccInlinePriv.c > +++ b/MdePkg/Library/BaseLib/X64/GccInlinePriv.c > @@ -80,7 +80,7 @@ AsmReadMsr64 ( > } > FilterAfterMsrRead (Index, &Value); > > - return (((UINT64)HighData) << 32) | LowData; > + return Value; > } > > /** > @@ -111,11 +111,10 @@ AsmWriteMsr64 ( > UINT32 HighData; > BOOLEAN Flag; > > - LowData = (UINT32)(Value); > - HighData = (UINT32)(Value >> 32); > - > Flag = FilterBeforeMsrWrite (Index, &Value); > if (Flag) { > + LowData = (UINT32)(Value); > + HighData = (UINT32)(Value >> 32); > __asm__ __volatile__ ( > "wrmsr" > : > -- > 2.31.1 > > > > > -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#73996): https://edk2.groups.io/g/devel/message/73996 Mute This Topic: https://groups.io/mt/82054853/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
