On 3/24/21 9:49 PM, gaoliming wrote: > Is this API X64 only? Or IA32 and X64 both?
Theoretically the instruction is available on both IA32 and X64 but its used only in X64. AMD SEV, SEV-ES and SEV-SNP support is available for X64 arch only. I was not sure if the EDK2 community is okay with the dead-code. Do you think it still makes sense to add the IA32 API for it ? > > Thanks > Liming >> -----邮件原件----- >> 发件人: devel@edk2.groups.io <devel@edk2.groups.io> 代表 Brijesh Singh >> 发送时间: 2021年3月24日 23:32 >> 收件人: devel@edk2.groups.io >> 抄送: Brijesh Singh <brijesh.si...@amd.com>; James Bottomley >> <j...@linux.ibm.com>; Min Xu <min.m...@intel.com>; Jiewen Yao >> <jiewen....@intel.com>; Tom Lendacky <thomas.lenda...@amd.com>; >> Jordan Justen <jordan.l.jus...@intel.com>; Ard Biesheuvel >> <ardb+tianoc...@kernel.org>; Laszlo Ersek <ler...@redhat.com> >> 主题: [edk2-devel] [RFC PATCH 09/19] MdePkg: Add AsmPvalidate() support >> >> BZ: >> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbugzilla.tianocore.org%2Fshow_bug.cgi%3Fid%3D3275&data=04%7C01%7Cbrijesh.singh%40amd.com%7C125d11ea64cf4f4ecd2108d8ef38a8e7%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637522373939810930%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=f3fM%2Fnw3X1lHhf7SPKTxDOLo0GcnU465yvyf0IIyD80%3D&reserved=0 >> >> The PVALIDATE instruction validates or rescinds validation of a guest >> page RMP entry. Upon completion, a return code is stored in EAX, rFLAGS >> bits OF, ZF, AF, PF and SF are set based on this return code. If the >> instruction completed succesfully, the rFLAGS bit CF indicates if the >> contents of the RMP entry were changed or not. >> >> For more information about the instruction see AMD APM volume 3. >> >> Cc: James Bottomley <j...@linux.ibm.com> >> Cc: Min Xu <min.m...@intel.com> >> Cc: Jiewen Yao <jiewen....@intel.com> >> Cc: Tom Lendacky <thomas.lenda...@amd.com> >> Cc: Jordan Justen <jordan.l.jus...@intel.com> >> Cc: Ard Biesheuvel <ardb+tianoc...@kernel.org> >> Cc: Laszlo Ersek <ler...@redhat.com> >> Signed-off-by: Brijesh Singh <brijesh.si...@amd.com> >> --- >> MdePkg/Include/Library/BaseLib.h | 37 +++++++++++++++++ >> MdePkg/Library/BaseLib/BaseLib.inf | 1 + >> MdePkg/Library/BaseLib/X64/Pvalidate.nasm | 43 ++++++++++++++++++++ >> 3 files changed, 81 insertions(+) >> >> diff --git a/MdePkg/Include/Library/BaseLib.h >> b/MdePkg/Include/Library/BaseLib.h >> index 1171a0ffb5..fee27e9a1b 100644 >> --- a/MdePkg/Include/Library/BaseLib.h >> +++ b/MdePkg/Include/Library/BaseLib.h >> @@ -7495,5 +7495,42 @@ PatchInstructionX86 ( >> IN UINTN ValueSize >> ); >> >> +/** >> + Execute a PVALIDATE instruction to validate or rescnids validation of a > guest >> + page's RMP entry. >> + >> + Upon completion, in addition to the return value the instruction also >> updates >> + the eFlags. A caller must check both the return code as well as eFlags > to >> + determine if the RMP entry has been updated. >> + >> + The function is available on x64. >> + >> + @param[in] Address The guest virtual address to validate. >> + @param[in] PageSize The page size to use. >> + @param[i] Validate Validate or rescinds. >> + @param[out] Eflags The value of Eflags after PVALIDATE >> completion. >> + >> + @retval PvalidateRetValue The return value from the PVALIDATE >> instruction. >> +**/ >> +typedef enum { >> + PVALIDATE_PAGE_SIZE_4K = 0, >> + PVALIDATE_PAGE_SIZE_2M, >> +} PvalidatePageSize; >> + >> +typedef enum { >> + PVALIDATE_RET_SUCCESS = 0, >> + PVALIDATE_RET_FAIL_INPUT = 1, >> + PVALIDATE_RET_FAIL_SIZEMISMATCH = 6, >> +} PvalidateRetValue; >> + >> +PvalidateRetValue >> +EFIAPI >> +AsmPvalidate ( >> + IN PvalidatePageSize PageSize, >> + IN BOOLEAN Validate, >> + IN UINTN Address, >> + OUT IA32_EFLAGS32 *Eflags >> + ); >> + >> #endif // defined (MDE_CPU_IA32) || defined (MDE_CPU_X64) >> #endif // !defined (__BASE_LIB__) >> diff --git a/MdePkg/Library/BaseLib/BaseLib.inf >> b/MdePkg/Library/BaseLib/BaseLib.inf >> index 3b85c56c3c..01aa5cc7a4 100644 >> --- a/MdePkg/Library/BaseLib/BaseLib.inf >> +++ b/MdePkg/Library/BaseLib/BaseLib.inf >> @@ -319,6 +319,7 @@ >> X64/RdRand.nasm >> X64/XGetBv.nasm >> X64/VmgExit.nasm >> + X64/Pvalidate.nasm >> ChkStkGcc.c | GCC >> >> [Sources.EBC] >> diff --git a/MdePkg/Library/BaseLib/X64/Pvalidate.nasm >> b/MdePkg/Library/BaseLib/X64/Pvalidate.nasm >> new file mode 100644 >> index 0000000000..f2aba114ac >> --- /dev/null >> +++ b/MdePkg/Library/BaseLib/X64/Pvalidate.nasm >> @@ -0,0 +1,43 @@ >> > +;-------------------------------------------------------------------------- > --- >> +; >> +; Copyright (c) 2020-2021, AMD. All rights reserved.<BR> >> +; SPDX-License-Identifier: BSD-2-Clause-Patent >> +; >> +; Module Name: >> +; >> +; Pvalidate.Asm >> +; >> +; Abstract: >> +; >> +; AsmPvalidate function >> +; >> +; Notes: >> +; >> > +;-------------------------------------------------------------------------- > --- >> + >> + SECTION .text >> + >> > +;-------------------------------------------------------------------------- > --- >> +; PvalidateRetValue >> +; EFIAPI >> +; AsmPvalidate ( >> +; IN UINT32 RmpPageSize >> +; IN UINT32 Validate, >> +; IN UINTN Address, >> +; OUT UINTN *Eflags, >> +; ) >> > +;-------------------------------------------------------------------------- > --- >> +global ASM_PFX(AsmPvalidate) >> +ASM_PFX(AsmPvalidate): >> + mov rax, r8 >> + >> + ; PVALIDATE instruction opcode >> + DB 0xF2, 0x0F, 0x01, 0xFF >> + >> + ; Read the Eflags >> + pushfq >> + pop r8 >> + mov [r9], r8 >> + >> + ; The PVALIDATE instruction returns the status in rax register. >> + ret >> -- >> 2.17.1 >> >> >> >> >> > > -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. 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