REF:https://bugzilla.tianocore.org/show_bug.cgi?id=1091
Previously, when compiling NASM source files, BaseTools did not support
including files outside of the NASM source file directory. As a result, we
duplicated multiple copies of "StuffRsb.inc" files in UefiCpuPkg. Those
INC files contain the common logic to stuff the Return Stack Buffer and
are identical.
After the fix of BZ 1085:
https://bugzilla.tianocore.org/show_bug.cgi?id=1085
The above support was introduced.
Thus, this commit will merge all the StuffRsb.inc files in UefiCpuPkg into
one file. The merged file will be named 'StuffRsbNasm.inc' and be placed
under folder UefiCpuPkg/Include/.
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1093
Return Stack Buffer (RSB) is used to predict the target of RET
instructions. When the RSB underflows, some processors may fall back to
using branch predictors. This might impact software using the retpoline
mitigation strategy on those processors.
This commit will add RSB stuffing logic before returning from SMM (the RSM
instruction) to avoid interfering with non-SMM usage of the retpoline
technique.
After the stuffing, RSB entries will contain a trap like:
@SpecTrap:
pause
lfence
jmp @SpecTrap
A more detailed explanation of the purpose of commit is under the
'Branch target injection mitigation' section of the below link:
https://software.intel.com/security-software-guidance/insights/host-firmware-speculative-execution-side-channel-mitigation
Please note that this commit requires further actions (BZ 1091) to remove
the duplicated 'StuffRsb.inc' files and merge them into one under a
UefiCpuPkg package-level directory (such as UefiCpuPkg/Include/).
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1091
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Rename the variable to "gPatchSmmInitStack" so that its association with
PatchInstructionX86() is clear from the declaration, change its type to
X86_ASSEMBLY_PATCH_LABEL, and patch it with PatchInstructionX86(). This
lets us remove the binary (DB) encoding of some instructions in
"SmmInit.nasm".
The size of the patched source operand is (sizeof (UINTN)).
Cc: Eric Dong <eric.dong@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=866
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
The IA32 version of "SmmInit.nasm" does not need "gSmmJmpAddr" at all (its
PiSmmCpuSmmInitFixupAddress() variant doesn't do anything either). We can
simply use the NASM syntax for the following Mixed-Size Jump:
> jmp PROTECT_MODE_CS : dword @32bit
The generated object code for the instruction is unchanged:
> 00000182 66EA5A0000000800 jmp dword 0x8:0x5a
(The NASM manual explains that putting the DWORD prefix after the colon
":" reflects the intent better, since it is the offset that is a DWORD.
Thus, that's what I used. However, both syntaxes are interchangeable,
hence the ndisasm output.)
The X64 version of "SmmInit.nasm" appears to require "gSmmJmpAddr";
however that's accidental, not inherent:
- Bring LONG_MODE_CODE_SEGMENT from
"UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h" to "SmmInit.nasm" as
LONG_MODE_CS, same as PROTECT_MODE_CODE_SEGMENT was brought to the IA32
version as PROTECT_MODE_CS earlier.
- Apply the NASM-native Mixed-Size Jump syntax again, but jump to the
fixed zero offset in LONG_MODE_CS. This will produce no relocation
record at all. Add a label after the instruction.
- Modify PiSmmCpuSmmInitFixupAddress() to patch the jump target backwards
from the label. Because we modify the DWORD offset with a DWORD access,
the segment selector is unharmed in the instruction, and we need not set
it from PiCpuSmmEntry().
According to "objdump --reloc", the X64 version undergoes only the
following relocations, after this patch:
> RELOCATION RECORDS FOR [.text]:
> OFFSET TYPE VALUE
> 0000000000000095 R_X86_64_PC32 SmmInitHandler-0x0000000000000004
> 00000000000000e0 R_X86_64_PC32 mRebasedFlag-0x0000000000000004
> 00000000000000ea R_X86_64_PC32 mSmmRelocationOriginalAddress-0x0000000000000004
Therefore the patch does not regress
<https://bugzilla.tianocore.org/show_bug.cgi?id=849> ("Enable XCODE5 tool
chain for UefiCpuPkg with nasm source code").
Cc: Eric Dong <eric.dong@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=866
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Like "gSmmCr4" in the previous patch, "gSmmCr0" is not only used for
machine code patching, but also as a means to communicate the initial CR0
value from SmmRelocateBases() to InitSmmS3ResumeState(). In other words,
the last four bytes of the "mov eax, Cr0Value" instruction's binary
representation are utilized as normal data too.
In order to get rid of the DB for "mov eax, Cr0Value", we have to split
both roles, patching and data flow. Introduce the "mSmmCr0" global (SMRAM)
variable for the data flow purpose. Rename the "gSmmCr0" variable to
"gPatchSmmCr0" so that its association with PatchInstructionX86() is clear
from the declaration, change its type to X86_ASSEMBLY_PATCH_LABEL, and
patch it with PatchInstructionX86(), to the value now contained in
"mSmmCr0".
This lets us remove the binary (DB) encoding of "mov eax, Cr0Value" in
"SmmInit.nasm".
Cc: Eric Dong <eric.dong@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=866
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Unlike "gSmmCr3" in the previous patch, "gSmmCr4" is not only used for
machine code patching, but also as a means to communicate the initial CR4
value from SmmRelocateBases() to InitSmmS3ResumeState(). In other words,
the last four bytes of the "mov eax, Cr4Value" instruction's binary
representation are utilized as normal data too.
In order to get rid of the DB for "mov eax, Cr4Value", we have to split
both roles, patching and data flow. Introduce the "mSmmCr4" global (SMRAM)
variable for the data flow purpose. Rename the "gSmmCr4" variable to
"gPatchSmmCr4" so that its association with PatchInstructionX86() is clear
from the declaration, change its type to X86_ASSEMBLY_PATCH_LABEL, and
patch it with PatchInstructionX86(), to the value now contained in
"mSmmCr4".
This lets us remove the binary (DB) encoding of "mov eax, Cr4Value" in
"SmmInit.nasm".
Cc: Eric Dong <eric.dong@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=866
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Rename the variable to "gPatchSmmCr3" so that its association with
PatchInstructionX86() is clear from the declaration, change its type to
X86_ASSEMBLY_PATCH_LABEL, and patch it with PatchInstructionX86(). This
lets us remove the binary (DB) encoding of some instructions in
"SmmInit.nasm".
Cc: Eric Dong <eric.dong@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=866
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
SMM emulation under both KVM and QEMU (TCG) crashes the guest when the
"jz" branch, added in commit d4d87596c1 ("UefiCpuPkg/PiSmmCpuDxeSmm:
Enable NXE if it's supported", 2018-01-18), is taken.
Rework the propagation of CPUID.80000001H:EDX.NX [bit 20] to IA32_EFER.NXE
[bit 11] so that no code is executed conditionally.
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Ref: http://mid.mail-archive.com/d6fff558-6c4f-9ca6-74a7-e7cd9d007276@redhat.com
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
[lersek@redhat.com: XD -> NX code comment updates from Ray]
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
[lersek@redhat.com: mark QEMU/TCG as well in the commit message]
The SmmStartup() executes in SMM, which is very similar to real mode. Add
"BITS 16" before it and "BITS 32" after it (just before the @32bit label).
Remove the manual 0x66 operand-size override prefixes, for selecting
32-bit operands -- the sizes of our operands trigger NASM to insert the
prefixes automatically in almost every spot. The one place where we have
to add it back manually is the LGDT instruction. (The 0x67 address-size
override prefix is also auto-generated.)
This patch causes NASM to generate byte-identical object code (determined
by disassembling both the pre-patch and post-patch versions, and comparing
the listings), except:
> @@ -158,7 +158,7 @@
> 00000142 6689D3 mov ebx,edx
> 00000145 66B800000000 mov eax,0x0
> 0000014B 0F22D8 mov cr3,eax
> -0000014E 67662E0F0155F6 o32 lgdt [cs:ebp-0xa]
> +0000014E 2E66670F0155F6 o32 lgdt [cs:ebp-0xa]
> 00000155 66B800000000 mov eax,0x0
> 0000015B 0F22E0 mov cr4,eax
> 0000015E 66B9800000C0 mov ecx,0xc0000080
The only difference is the prefix list order, it changes from:
- 0x67, 0x66, 0x2E
to
- 0x2E, 0x66, 0x67
(0x2E is "CS segment override").
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=866
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
The gSmmCr3, gSmmCr4, gSmmCr0 and gSmmJmpAddr global variables are used
for patching assembly instructions, thus we can't yet remove the DB
encodings for those instructions. At least we should add the intended
meanings in comments.
This patch only changes comments.
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
[lersek@redhat.com: adapt commit msg to ongoing PatchAssembly discussion]
If PcdDxeNxMemoryProtectionPolicy is set to enable protection for memory
of EfiBootServicesCode, EfiConventionalMemory, the BIOS will hang at a page
fault exception triggered by PiSmmCpuDxeSmm.
The root cause is that PiSmmCpuDxeSmm will access default SMM RAM starting
at 0x30000 which is marked as non-executable, but NX feature was not
enabled during SMM initialization. Accessing memory which has invalid
attributes set will cause page fault exception. This patch fixes it by
checking NX capability in cpuid and enable NXE in EFER MSR if it's
available.
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
https://bugzilla.tianocore.org/show_bug.cgi?id=849
In V2, use "mov rax, strict qword 0" to replace the hard code db.
1. Use lea instruction to get the address instead of mov instruction.
2. Use the dummy address as jmp destination, and add the logic to fix up
the address to the absolute address at boot time.
3. On MpFuncs.nasm, use ExchangeInfo to record InitializeFloatingPointUnits.
This way is same to MpInitLib.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
Cc: Andrew Fish <afish@apple.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Commits 28ee581646 and 246cd9085f added these ENDs as part of the
manual conversion from *.asm files. However, the ENDs makes no sense for
NASM. Although they don't break the build, NASM complains about them:
label alone on a line without a colon might be in error
(This NASM warning category dates back to NASM 0.95, commit
6768eb71d8deb.)
Remove the ENDs.
Cc: Jeff Fan <jeff.fan@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Michael D Kinney
Hao Wu
Laszlo Ersek
Jian J Wang
Liming Gao