Commit Graph

923 Commits

Author SHA1 Message Date
Ruiyu Ni 34c3405cb7 UefiCpuPkg/PeiCpuException: Fix coding style issue
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Dandan Bi <dandan.bi@intel.com>
2018-09-10 10:22:27 +08:00
Jian J Wang 0a0d5296e4 UefiCpuPkg/CpuMpPei: support stack guard feature
This feature is the same as Stack Guard enabled in driver CpuDxe but
applies to PEI phase. Due to the specialty in PEI module dispatching,
this driver is changed to do the actual initialization in notify
callback of event gEfiPeiMemoryDiscoveredPpiGuid. This can let the
stack guard apply to as most PEI drivers as possible.

To let Stack Guard work, some simple page table management code are
introduced to setup Guard page at base of stack for each processor.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: "Ware, Ryan R" <ryan.r.ware@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
2018-09-10 09:28:28 +08:00
Jian J Wang e09b6b5953 UefiCpuPkg/MpInitLib: fix register restore issue in AP wakeup
The conflict issues are introduced by Stack Guard feature enabled for
PEI.

The first is CR0 which should be restored after CR3 and CR4.
Another is TR which should not be passed from BSP to AP during init
phase.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: "Ware, Ryan R" <ryan.r.ware@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
2018-09-10 09:28:27 +08:00
Jian J Wang fc0e7fd5e8 UefiCpuPkg/CpuExceptionHandlerLib: support stack switch for PEI exceptions
Stack Guard needs to setup stack switch capability to allow exception
handler to be called with good stack if stack overflow is detected.
This patch update InitializeCpuExceptionHandlersEx() to allow pass
extra initialization data used to setup exception stack switch for
specified exceptions.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: "Ware, Ryan R" <ryan.r.ware@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
2018-09-10 09:28:26 +08:00
Eric Dong e23d9c3ed8 UefiCpuPkg/MpInitLib: Fix ECC issues.
Fix trailing white spaces and invalid line ending issue.

Cc: Dandan Bi <dandan.bi@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Dandan Bi <dandan.bi@intel.com>
2018-09-06 08:04:29 +08:00
Ruiyu Ni 374168ae65 UefiCpuPkg/CpuExceptionHandlerLib: Avoid calling PEI services from AP
When an exception happens in AP, system hangs at
GetPeiServicesTablePointer(), complaining the PeiServices retrieved
from memory before IDT is NULL.

Due to the following commit:
c563077a38
* UefiCpuPkg/MpInitLib: Avoid calling PEI services from AP
the IDT used by AP no longer preserve PeiServices pointer in the
very beginning.
But the implementation of PeiExceptionHandlerLib still assumes
the PeiServices pointer is there, so the assertion happens.

The patch fixes the exception handler library to not call
PEI services from AP.

The patch duplicates the #0 exception stub header in an allocated
pool but with extra 4-byte/8-byte to store the exception handler
data which was originally stored in HOB.
When AP exception happens, the code gets the exception handler data
from the exception handler for #0.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Fan Jeff <vanjeff_919@hotmail.com>
2018-09-03 14:02:26 +08:00
Ruiyu Ni 87a9dd0d15 CpuExceptionHandlerLib: Add comments to make code more readable
Today's implementation of handling HOOK_BEFORE and HOOK_AFTER is
a bit complex. More comments is better.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Fan Jeff <vanjeff_919@hotmail.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
2018-09-03 14:02:24 +08:00
Jian J Wang 7c7c8190d3 UefiCpuPkg/CpuDxe: change level of DEBUG message
BZ#1127: https://bugzilla.tianocore.org/show_bug.cgi?id=1127

It's reported the debug message in CpuDxe driver is quite annoying in
boot and shell, and slow down the boot process. To solve this issue,
this patch changes the DEBUG_INFO to DEBUG_VERBOSE. On a typical Intel
real platform, at least 16s boot time can be saved.

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>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2018-08-30 07:43:56 +08:00
Jian J Wang 09afd9a42a UefiCpuPkg/PiSmmCpuDxeSmm: implement non-stop mode for SMM
Since SMM profile feature has already implemented non-stop mode if #PF
occurred, this patch just makes use of the existing implementation to
accommodate heap guard and NULL pointer detection feature.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.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>
Acked-by: Laszlo Ersek <lersek@redhat.com>
2018-08-30 07:22:30 +08:00
Jian J Wang dcc026217f UefiCpuPkg/CpuDxe: implement non-stop mode for uefi
Same as SMM profile feature, a special #PF is used to set page attribute
to 'present' and a special #DB handler to reset it back to 'not-present',
right after the instruction causing #PF got executed.

Since the new #PF handler won't enter into dead-loop, the instruction
which caused the #PF will get chance to re-execute with accessible pages.

The exception message will still be printed out on debug console so that
the developer/QA can find that there's potential heap overflow or null
pointer access occurred.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.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>
Acked-by: Laszlo Ersek <lersek@redhat.com>
2018-08-30 07:22:30 +08:00
Jian J Wang 16b918bbaf UefiCpuPkg/CpuExceptionHandlerLib: Setup single step in #PF handler
Once the #PF handler has set the page to be 'present', there should
be a way to reset it to 'not-present'. 'TF' bit in EFLAGS can be used
for this purpose. 'TF' bit will be set in interrupted function context
so that it can be triggered once the cpu control returns back to the
instruction causing #PF and re-execute it.

This is an necessary step to implement non-stop mode for Heap Guard
and NULL Pointer Detection feature.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.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>
Acked-by: Laszlo Ersek <lersek@redhat.com>
2018-08-30 07:22:29 +08:00
Laszlo Ersek 0442a9a9f4 UefiCpuPkg/PiSmmCpuDxeSmm: clear exec file mode bits on "PiSmmCpuDxeSmm.c"
Commit 241f914975 ("UefiCpuPkg/PiSmmCpuDxeSmm: Add support for PCD
PcdPteMemoryEncryptionAddressOrMask", 2017-03-01) unintentionally set the
executable file mode bits on "PiSmmCpuDxeSmm.c"; clear them now.

Cc: Eric Dong <eric.dong@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1092
Fixes: 241f914975
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2018-08-22 10:33:49 +02:00
Hao Wu 0df5056012 UefiCpuPkg/SmmCpuFeaturesLib: [CVE-2017-5715] Stuff RSB before RSM
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>
Reviewed-by: Eric Dong <eric.dong@intel.com>
2018-08-21 16:11:15 +08:00
Hao Wu 02f7fd158e UefiCpuPkg/PiSmmCpuDxeSmm: [CVE-2017-5715] Stuff RSB before RSM
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>
2018-08-21 16:10:42 +08:00
Eric Dong a6daab1f6c UefiCpuPkg/RegisterCpuFeaturesLib: Combine implementation.
V1 changes:
> Current code logic can't confirm CpuS3DataDxe driver start before
> CpuFeaturesDxe driver. So the assumption in CpuFeaturesDxe not valid.
> Add implementation for AllocateAcpiCpuData function to remove this
> assumption.

V2 changes:
> Because CpuS3Data memory will be copy to smram at SmmReadToLock point,
> so the memory type no need to be ACPI NVS type, also the address not
> limit to below 4G.
> This change remove the limit of ACPI NVS memory type and below 4G.

V3 changes:
> Remove function definition in header file.
> Add STATIC in function implementation.

Pass OS boot and resume from S3 test.

Bugz: https://bugzilla.tianocore.org/show_bug.cgi?id=959

Reported-by: Marvin Häuser <Marvin.Haeuser@outlook.com>
Suggested-by: Fan Jeff <vanjeff_919@hotmail.com>
Cc: Marvin Häuser <Marvin.Haeuser@outlook.com>
Cc: Fan Jeff <vanjeff_919@hotmail.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
2018-08-16 08:42:01 +08:00
Eric Dong 6eab8b4368 UefiCpuPkg/CpuS3DataDxe: Remove below 4G limitation.
Because PrepareApStartupVector() stores StackAddress to
"mExchangeInfo->StackStart" (which has type (VOID*)), and because
"UefiCpuPkg/PiSmmCpuDxeSmm/X64/MpFuncs.nasm" reads the latter with:

         add  edi, StackStartAddressLocation
         add  rax, qword [edi]
         mov  rsp, rax
         mov  qword [edi], rax

in long-mode code. So code can remove below 4G limitation.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
2018-08-16 08:42:01 +08:00
Eric Dong b581721063 UefiCpuPkg/CpuS3DataDxe: Change Memory Type and address limitation.
Because CpuS3Data memory will be copy to smram at SmmReadyToLock point,
the memory type no need to be ACPI NVS type, also the address not
limit to below 4G.

This change remove the limit of ACPI NVS memory type and below 4G.

Pass OS boot and resume from S3 test.

Cc: Marvin Häuser <Marvin.Haeuser@outlook.com>
Cc: Fan Jeff <vanjeff_919@hotmail.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
2018-08-16 08:42:01 +08:00
Eric Dong fcd92f16af UefiCpuPkg/AcpiCpuData.h: Remove AcpiNVS and Below 4G limitation.
ACPI_CPU_DATA structure first introduced to save data in
normal boot phase. Also this data will be used in S3 phase
by one PEI driver. So in first phase, this data is been
defined to use ACPI NVS memory type and must below 4G.

Later in order to fix potential security issue,
PiSmmCpuDxeSmm driver added logic to copy ACPI_CPU_DATA
(except ResetVector and Stack buffer) to  smram at smm
ready to lock point. ResetVector must below 1M and Stack
buffer is write only in S3 phase, so these two fields not
copy to smram. Also PiSmmCpuDxeSmm driver owned the task
to restore the CPU setting and it's a SMM driver.

After above change, the acpi nvs memory type and below 4G
limitation is no longer needed.

This change remove the limitation in the comments for
ACPI_CPU_DATA definition.

Cc: Marvin Häuser <Marvin.Haeuser@outlook.com>
Cc: Fan Jeff <vanjeff_919@hotmail.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
2018-08-16 08:42:00 +08:00
Eric Dong 293f876618 UefiCpuPkg/PiSmmCpuDxeSmm: Use GDT/IDT saved in Smram.
Current implementation will copy GDT/IDT at SmmReadyToLock point
from ACPI NVS memory to Smram. Later at S3 resume phase, it restore
the memory saved in Smram to ACPI NVS. It can directly use GDT/IDT
saved in Smram instead of restore the original ACPI NVS memory.
This patch do this change.

Test Done:
  Do the OS boot and S3 resume test.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
2018-08-16 08:42:00 +08:00
Chen A Chen 667abfaf8a UefiCpuPkg: Removing ipf which is no longer supported from edk2.
Merge [Sources.Ia32, Sources.X64] to [Sources] after removing IPF. Also
change other similar parts in this file.

Cc: Eric Dong <eric.dong@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Chen A Chen <chen.a.chen@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
2018-08-14 08:58:28 +08:00
Hao Wu 6d9a0a9420 UefiCpuPkg/PiSmmCpuDxeSmm: Avoid possible NULL ptr dereference
Within function GetUefiMemoryAttributesTable(), add a check to avoid
possible null pointer dereference.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
2018-07-31 13:07:47 +08:00
Jiewen Yao 8a2e1a9d54 UefiCpuPkg/PiSmmCpu: Check EFI_RUNTIME_RO in UEFI mem attrib table.
It treats the UEFI runtime page with EFI_MEMORY_RO attribute as
invalid SMM communication buffer.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2018-07-26 22:51:26 +08:00
Jiewen Yao ac6613db46 UefiCpuPkg/PiSmmCpu: Check for untested memory in GCD
It treats GCD untested memory as invalid SMM
communication buffer.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
2018-07-26 22:51:22 +08:00
Eric Dong cf4e79e466 UefiCpuPkg/MpInitLib: Not use disabled AP when call StartAllAPs.
Base on UEFI spec requirement, StartAllAPs function should not use the APs which has been disabled before. This patch just change current code to follow this rule.

V3 changes:
Only called by StartUpAllAps, WakeUpAp will not wake up the disabled APs, in other cases also need to include the disabled APs, such as CpuDxe driver start up and ChangeApLoopCallback function.

WakeUpAP() is called with (Broadcast && WakeUpDisabledAps) from MpInitLibInitialize(), CollectProcessorCount() and MpInitChangeApLoopCallback() only. The first two run before the PPI or Protocol user has a chance to disable any APs. The last one runs in response to the ExitBootServices and LegacyBoot events, after which the MP protocol is unusable. For this reason, it doesn't matter that an originally disabled AP's state is not restored to Disabled, when
WakeUpAP() is called with (Broadcast && WakeUpDisabledAps).

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
2018-07-26 16:54:18 +08:00
Eric Dong 2da3e96cb7 UefiCpuPkg/MpInitLib: Remove StartCount and volatile definition.
The patch includes below changes:
(1) It removes "volatile" from RunningCount, because only the BSP modifies it.
(2) When we detect a timeout in CheckAllAPs(), and collect the list of failed CPUs, the size of the list is derived from the following difference, before the patch:
  StartCount - FinishedCount
where "StartCount" is set by the BSP at startup, and FinishedCount is incremented by the APs themselves.
Here the patch replaces this difference with
  StartCount - RunningCount
that is, the difference is no more calculated from the BSP's startup counter and the AP's shared finish counter, but from the RunningCount measurement that the BSP does itself, in CheckAllAPs().
(3) Finally, the patch changes the meaning of RunningCount. Before the patch, we have:
- StartCount: the number of APs the BSP stars up,
- RunningCount: the number of finished APs that the BSP collected
After the patch, StartCount is removed, and RunningCount is *redefined* as the following difference:
  OLD_StartCount - OLD_RunningCount
Giving the number of APs that the BSP started up but hasn't collected yet.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
2018-07-26 16:54:14 +08:00
Eric Dong 2a5997f899 UefiCpuPkg/MpInitLib: Remove redundant CpuStateFinished State.
Current CPU state definition include CpuStateIdle and CpuStateFinished.
After investigation, current code can use CpuStateIdle to replace the
CpuStateFinished. It will reduce the state number and easy for maintenance.

> Before this patch, the state transitions for an AP are:
>
>   Idle ----> Ready ----> Busy ----> Finished ----> Idle
>        [BSP]       [AP]       [AP]           [BSP]
>
> After the patch, the state transitions for an AP are:
>
>   Idle ----> Ready ----> Busy ----> Idle
>        [BSP]       [AP]       [AP]

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
2018-07-26 16:54:09 +08:00
Marvin H?user 005c855dc6 UefiCpuPkg/CpuMpPei: Correct BIST PPI logic.
Currently, the SecPlatformInformation2 PPI is installed when either
there is none present or the present one doesn't lack data.
Update the logic to only install the SecPlatformInformation2 PPI when
it's not already installed so that an up-to-date PPI remains the only
one and unchanged.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Marvin Haeuser <Marvin.Haeuser@outlook.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
2018-07-24 08:35:33 +08:00
Jian J Wang b72f487372 UefiCpuPkg/CpuDxe: fix incorrect check of SMM mode
Current IsInSmm() method makes use of gEfiSmmBase2ProtocolGuid.InSmm() to
check if current processor is in SMM mode or not. But this is not correct
because gEfiSmmBase2ProtocolGuid.InSmm() can only detect if the caller is
running in SMRAM or from SMM driver. It cannot guarantee if the caller is
running in SMM mode. Because SMM mode will load its own page table, adding
an extra check of saved DXE page table base address against current CR3
register value can help to get the correct answer for sure (in SMM mode or
not in SMM mode).

There's indiscriminate uses of Context.X64 and Context.Ia32 in code which
is not a good coding practice and will cause potential issue. In addition,
the related structure type definition is not packed and has also potential
issue. This will not be covered by this patch but be tracked by a bug below.

  https://bugzilla.tianocore.org/show_bug.cgi?id=1039

This is an issue caused by check-in at

  2a1408d1d7

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Star Zeng <star.zeng@intel.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>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
2018-07-20 10:34:11 +08:00
Eric Dong 9b7242f5de UefiCpuPkg/MpInitLib: Fix VS2012 build failure
Cc: Eric Dong <eric.dong@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
2018-07-20 09:36:41 +08:00
Eric Dong a234383c5b UefiCpuPkg/MpInitLib: Remove useless code.
Remove the useless code error added by change
58942277bc.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2018-07-20 09:24:42 +08:00
Eric Dong e52838d358 UefiCpuPkg/MpInitLib: Optimize get processor number performance.
Current function has low performance because it calls GetApicId
in the loop, so it maybe called more than once.

New logic call GetApicId once and base on this value to search
the processor.

Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Jeff Fan <vanjeff_919@hotmail.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2018-07-20 09:24:42 +08:00
Eric Dong 58942277bc UefiCpuPkg/MpInitLib: Fix S3 resume hang issue.
When resume from S3 and CPU loop mode is MWait mode,
if driver calls APs to do task at EndOfPei point, the
APs can't been wake up and bios hang at that point.

The root cause is PiSmmCpuDxeSmm driver wakes up APs
with HLT mode during S3 resume phase to do SMM relocation.
After this task, PiSmmCpuDxeSmm driver not restore APs
context which make CpuMpPei driver saved wake up buffer
not works.

The solution for this issue is let CpuMpPei driver hook
S3SmmInitDone ppi notification. In this notify function,
it check whether Cpu Loop mode is not HLT mode. If yes,
CpuMpPei driver will set a flag to force BSP use INIT-SIPI
-SIPI command to wake up the APs.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
2018-07-19 13:06:49 +08:00
Eric Dong f63a3e2867 UefiCpuPkg/MpInitLib: Load uCode once for each core.
The SDM requires only one thread per core to load the
microcode.

This change enables this solution.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
2018-07-18 12:43:30 +08:00
Eric Dong 2a08913443 UefiCpuPkg/MpInitLib: Use BSP uCode for APs if possible.
Search uCode costs much time, if AP has same processor type
with BSP, AP can use BSP saved uCode info to get better performance.

This change enables this solution.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
2018-07-18 12:43:30 +08:00
Eric Dong 6936ee0342 UefiCpuPkg/MpInitLib: Relocate uCode to memory to save time.
Read uCode from memory has better performance than from flash.
But it needs extra effort to let BSP copy uCode from flash to
memory. Also BSP already enable cache in SEC phase, so it use
less time to relocate uCode from flash to memory. After
verification, if system has more than one processor, it will
reduce some time if load uCode from memory.

This change enable this optimization.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
2018-07-18 12:43:29 +08:00
Ni, Ruiyu c563077a38 UefiCpuPkg/MpInitLib: Avoid calling PEI services from AP
Today's MpInitLib PEI implementation directly calls
PeiServices->GetHobList() from AP which may cause racing issue.

This patch fixes this issue by duplicating IDT for APs.
Because CpuMpData structure is stored just after IDT, the CpuMPData
address equals to IDTR.BASE + IDTR.LIMIT + 1.

v2:
  1. Add ALIGN_VALUE() on BufferSize.
  2. Add ASSERT() to make sure no memory usage outside of the allocated buffer.
  3. Add more comments in InitConfig path when restoring CpuData[0].VolatileRegisters.

Cc: Jeff Fan <vanjeff_919@hotmail.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Fish Andrew <afish@apple.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
2018-07-12 10:56:56 +08:00
chenc2 f6b0258d25 UefiCpuPkg: Removing ipf which is no longer supported from edk2.
Removing rules for Ipf sources file:
* Remove the source file which path with "ipf" and also listed in
  [Sources.IPF] section of INF file.
* Remove the source file which listed in [Components.IPF] section
  of DSC file and not listed in any other [Components] section.
* Remove the embedded Ipf code for MDE_CPU_IPF.

Removing rules for Inf file:
* Remove IPF from VALID_ARCHITECTURES comments.
* Remove DXE_SAL_DRIVER from LIBRARY_CLASS in [Defines] section.
* Remove the INF which only listed in [Components.IPF] section in DSC.
* Remove statements from [BuildOptions] that provide IPF specific flags.
* Remove any IPF sepcific sections.

Removing rules for Dec file:
* Remove [Includes.IPF] section from Dec.

Removing rules for Dsc file:
* Remove IPF from SUPPORTED_ARCHITECTURES in [Defines] section of DSC.
* Remove any IPF specific sections.
* Remove statements from [BuildOptions] that provide IPF specific flags.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Chen A Chen <chen.a.chen@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
2018-06-29 16:19:52 +08:00
Liming Gao 7367cc6c24 UefiCpuPkg: Clean up source files
1. Do not use tab characters
2. No trailing white space in one line
3. All files must end with CRLF

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
2018-06-28 11:19:53 +08:00
Bi, Dandan e57350403e UefiCpuPkg: Use new added Perf macros
Replace old Perf macros with the new added ones.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
2018-06-26 15:37:06 +08:00
Jian J Wang d106cf71ea UefiCpuPkg/CpuDxe: make register access more readable
Update code to use more meaningful constant macro or predefined
register structure.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
2018-06-19 13:44:55 +08:00
Jian J Wang 2a1408d1d7 UefiCpuPkg/CpuDxe: allow accessing (DXE) page table in SMM mode
The MdePkg/Library/SmmMemoryAllocationLib, used only by DXE_SMM_DRIVER,
allows to free memory allocated in DXE (before EndOfDxe). This is done
by checking the memory range and calling gBS services to do real
operation if the memory to free is out of SMRAM. If some memory related
features, like Heap Guard, are enabled, gBS interface will turn to
EFI_CPU_ARCH_PROTOCOL.SetMemoryAttributes(), provided by
DXE driver UefiCpuPkg/CpuDxe, to change memory paging attributes. This
means we have part of DXE code running in SMM mode in certain
circumstances.

Because page table in SMM mode is different from DXE mode and CpuDxe
always uses current registers (CR0, CR3, etc.) to get memory paging
attributes, it cannot get the correct attributes of DXE memory in SMM
mode from SMM page table. This will cause incorrect memory manipulations,
like fail the releasing of Guard pages if Heap Guard is enabled.

The solution in this patch is to store the DXE page table information
(e.g. value of CR0, CR3 registers, etc.) in a global variable of CpuDxe
driver. If CpuDxe detects it's in SMM mode, it will use this global
variable to access page table instead of current processor registers.
This can avoid retrieving wrong DXE memory paging attributes and changing
SMM page table attributes unexpectedly.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
2018-06-19 13:44:54 +08:00
Eric Dong bf252e29a5 UefiCpuPkg/LocalApicLib: Exclude second SendIpi sequence on AMD processors.
On AMD processors the second SendIpi in the SendInitSipiSipi and
SendInitSipiSipiAllExcludingSelf routines is not required, and may cause
undesired side-effects during MP initialization.

This patch leverages the StandardSignatureIsAuthenticAMD check to exclude
the second SendIpi and its associated MicroSecondDelay (200).

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Leo Duran <leo.duran@amd.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Jeff Fan <jeff.fan@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2018-06-19 13:15:39 +08:00
Liming Gao 236601136f UefiCpuPkg: Remove X86 ASM and S files
NASM has replaced ASM and S files.
1. Remove ASM from all modules expect for the ones in ResetVector directory.
The ones in ResetVector directory are included by Vtf0.nasmb. They are
also nasm style.
2. Remove S files from the drivers only.
3. https://bugzilla.tianocore.org/show_bug.cgi?id=881
After NASM is updated, S files can be removed from Library.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2018-06-07 15:27:36 +08:00
Ruiyu Ni 60cb4d1b04 UefiCpuPkg/CpuCommonFeatures: Follow SDM for MAX CPUID feature detect
According to IA manual:
"Before setting this bit (MSR_IA32_MISC_ENABLE[22]) , BIOS must
execute the CPUID.0H and examine the maximum value returned in
EAX[7:0]. If the maximum value is greater than 2, this bit is
supported."

We need to fix our current detection logic to compare against 2.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Cc: Ming Shao <ming.shao@intel.com>
2018-05-28 14:59:19 +08:00
Marvin H?user 7cd8a57599 UefiCpuPkg/SecMain: Add NORETURN decorator to SecStartup().
The function SecStartup() is not supposed to return. Hence, add the
NORETURN decorator.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Marvin Haeuser <Marvin.Haeuser@outlook.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2018-05-08 19:45:45 +08:00
Star Zeng 3e5c6c07b1 UefiCpuPkg MpInitLib: Fix typo "sCPUID" to "CPUID"
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
2018-04-25 15:19:34 +08:00
Laszlo Ersek d22c995a48 UefiCpuPkg/PiSmmCpuDxeSmm: use mnemonics for FXSAVE(64)/FXRSTOR(64)
NASM introduced FXSAVE / FXRSTOR support in commit 900fa5b26b8f ("NASM
0.98p3-hpa", 2002-04-30), which commit stands for the nasm-0.98p3-hpa
release.

NASM introduced FXSAVE64 / FXRSTOR64 support in commit 3a014348ca15
("insns: add FXSAVE64/FXRSTOR64, drop np prefix", 2010-07-07), which was
part of the "nasm-2.09" release.

Edk2 requires nasm-2.10 or later for use with the GCC toolchain family,
and nasm-2.12.01 or later for use with all other toolchain families.
Replace the binary encoding of the FXSAVE(64)/FXRSTOR(64) instructions
with mnemonics.

I verified that the "Ia32/SmiException.obj", "X64/SmiEntry.obj" and
"X64/SmiException.obj" files are rebuilt after this patch, without any
change in content.

This patch removes the last instructions encoded with DBs from
PiSmmCpuDxeSmm.

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>
2018-04-04 16:44:27 +02:00
Laszlo Ersek 9686a4678d UefiCpuPkg/PiSmmCpuDxeSmm: remove DBs from SmmRelocationSemaphoreComplete32()
(1) SmmRelocationSemaphoreComplete32() runs in 32-bit mode, so wrap it in
    a (BITS 32 ... BITS 64) bracket.

(2) SmmRelocationSemaphoreComplete32() currently compiles to:

> 000002AE  C6050000000001    mov byte [dword 0x0],0x1
> 000002B5  FF2500000000      jmp dword [dword 0x0]

    where the first instruction is patched with the contents of
    "mRebasedFlag" (so that (*mRebasedFlag) is set to 1), and the second
    instruction is patched with the address of
    "mSmmRelocationOriginalAddress" (so that we jump to
    "mSmmRelocationOriginalAddress").

    In its current form the first instruction could not be patched with
    PatchInstructionX86(), given that the operand to patch is not encoded
    in the trailing bytes of the instruction. Therefore, adopt an
    EAX-based version, inspired by both the IA32 and X64 variants of
    SmmRelocationSemaphoreComplete():

> 000002AE  50                push eax
> 000002AF  B800000000        mov eax,0x0
> 000002B4  C60001            mov byte [eax],0x1
> 000002B7  58                pop eax
> 000002B8  FF2500000000      jmp dword [dword 0x0]

    Here both instructions can be patched with PatchInstructionX86(), and
    the DBs can be replaced with native NASM syntax.

(3) Turn the "mRebasedFlagAddr32" and "mSmmRelocationOriginalAddressPtr32"
    variables into markers that suit PatchInstructionX86().

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>
2018-04-04 16:44:25 +02:00
Laszlo Ersek 5830d2c399 UefiCpuPkg/PiSmmCpuDxeSmm: patch "gSmmInitStack" with PatchInstructionX86()
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>
2018-04-04 16:44:23 +02:00
Laszlo Ersek 456c4ccab2 UefiCpuPkg/PiSmmCpuDxeSmm: eliminate "gSmmJmpAddr" and related DBs
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>
2018-04-04 16:44:19 +02:00