From: Ceping Sun <cepingx....@intel.com> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4572
According to section 3.2 of the [GHCI] spec, if the return status of MapGPA is "TDG.VP.VMCALL_RETRY", TD must retry this operation for the pages in the region starting at the GPA specified in R11. Currently, TDVF has not handled the retry results and always clears the R11 on unsuccessful return status. For this, the TdVmcall needs to output the value of R11 on unsuccessful return status to handle the retry results of MapGPA. Reference: [GHCI]: TDX Guest-Host-Communication Interface v1.0 https://cdrdv2.intel.com/v1/dl/getContent/726790 Cc: Liming Gao <gaolim...@byosoft.com.cn> Cc: Michael D Kinney <michael.d.kin...@intel.com> Cc: Erdem Aktas <erdemak...@google.com> Cc: James Bottomley <j...@linux.ibm.com> Cc: Jiewen Yao <jiewen....@intel.com> Cc: Min Xu <min.m...@intel.com> Cc: Tom Lendacky <thomas.lenda...@amd.com> Cc: Michael Roth <michael.r...@amd.com> Cc: Gerd Hoffmann <kra...@redhat.com> Signed-off-by: Ceping Sun <cepingx....@intel.com> --- MdePkg/Library/BaseLib/X64/TdVmcall.nasm | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/MdePkg/Library/BaseLib/X64/TdVmcall.nasm b/MdePkg/Library/BaseLib/X64/TdVmcall.nasm index 5ecc10b17193..8dd9bfcbfa14 100644 --- a/MdePkg/Library/BaseLib/X64/TdVmcall.nasm +++ b/MdePkg/Library/BaseLib/X64/TdVmcall.nasm @@ -133,9 +133,7 @@ ASM_PFX(TdVmCall): test r9, r9 jz .no_return_data - ; On success, propagate TDVMCALL output value to output param - test rax, rax - jnz .no_return_data + ; Propagate TDVMCALL output value to output param mov [r9], r11 .no_return_data: tdcall_regs_postamble -- 2.34.1 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#110506): https://edk2.groups.io/g/devel/message/110506 Mute This Topic: https://groups.io/mt/102337975/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
