Commit Graph

152 Commits

Author SHA1 Message Date
Ning Feng 88a4de450f UefiCpuPkg/MpLib:Do not assume BSP is #0.
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4778

MPInitlib have wrong expectation that BSP index should always be 0 in
MpInitLibInitialize(), SwitchBsp(),ApWakeupFunction().
That will cause the data mismatch, if the initial BSP is not 0.

Reviewed-by: Ray Ni <ray.ni@intel.com>
Signed-off-by: Ning Feng <ning.feng@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Jiaxin Wu <jiaxin.wu@intel.com>
2024-05-27 10:04:25 +08:00
Tom Lendacky 5bdb091133 UefiCpuPkg/MpInitLib: Always use AP Create if GhcbApicIds HOB is present
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4654

Currently, the first time an AP is started for an SEV-SNP guest, it relies
on the VMSA as set by the hypervisor. If the list of APIC IDs has been
retrieved, this is not necessary. The list of APIC IDs will be identified
by a GUIDed HOB. If the GUIDed HOB is present, use the SEV-SNP AP Create
protocol to start the AP for the first time and each time thereafter.

Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Acked-by: Ray Ni <ray.ni@intel.com>
2024-04-17 18:30:03 +00:00
Gerd Hoffmann dc7cfa9bab UefiCpuPkg/MpInitLib: add struct MP_HAND_OFF_CONFIG
Move the WaitLoopExecutionMode and StartupSignalValue fields to a
separate HOB with the new struct.

WaitLoopExecutionMode and StartupSignalValue are independent of
processor index ranges; they are global to MpInitLib (i.e., the entire
system). Therefore they shouldn't be repeated in every MpHandOff GUID
HOB.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-Id: <20240228114855.1615788-1-kraxel@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Oliver Steffen <osteffen@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
[lersek@redhat.com: turn the "Cc:" message headers from Gerd's on-list
 posting into "Cc:" tags in the commit message, in order to pacify
 "PatchCheck.py"]
2024-02-29 09:56:38 +00:00
Gerd Hoffmann d25421d0d8 UefiCpuPkg/MpInitLib: return early in GetBspNumber()
After finding the BSP Number return the result instead of
continuing to loop over the remaining processors.

Suggested-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-Id: <20240222160106.686484-7-kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
[lersek@redhat.com: s/ASSERT (FALSE)/ASSERT_EFI_ERROR (EFI_NOT_FOUND)/ [Ray]]
2024-02-26 21:56:21 +00:00
Gerd Hoffmann c8e77454b5 UefiCpuPkg/MpInitLib: Add support for multiple HOBs to MpInitLibInitialize
Loop over all MP_HAND_OFF HOBs instead of expecting a single HOB
covering all CPUs in the system.

Add a new FirstMpHandOff variable, which caches the first HOB body for
faster lookups.  It is also used to check whenever MP_HAND_OFF HOBs are
present.  Using the MpHandOff pointer for that does not work any more
because the variable will be NULL at the end of HOB loops.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Message-Id: <20240222160106.686484-5-kraxel@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2024-02-26 21:56:21 +00:00
Gerd Hoffmann e2c9d8eba4 UefiCpuPkg/MpInitLib: Add support for multiple HOBs to SwitchApContext()
Rename the MpHandOff parameter to FirstMpHandOff.  Add loops so the
function inspects all HOBs present in the system.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20240222160106.686484-4-kraxel@redhat.com>
2024-02-26 21:56:21 +00:00
Gerd Hoffmann b485230462 UefiCpuPkg/MpInitLib: Add support for multiple HOBs to GetBspNumber()
Rename the MpHandOff parameter to FirstMpHandOff.  Add a loop so the
function inspects all HOBs present in the system.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20240222160106.686484-3-kraxel@redhat.com>
2024-02-26 21:56:21 +00:00
Gerd Hoffmann a3ee1eea96 UefiCpuPkg/MpInitLib: Add support for multiple HOBs to GetMpHandOffHob
Rename the function to GetNextMpHandOffHob(), add MP_HAND_OFF parameter.
When called with NULL pointer return the body of the first HOB, otherwise
return the next in the chain.

Also add the function prototype to the MpLib.h header file.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-Id: <20240222160106.686484-2-kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2024-02-26 21:56:21 +00:00
duntan 2a5c08caaf UefiCpuPkg: set EXTENDED_PROCESSOR_INFORMATION to 0
Set EXTENDED_PROCESSOR_INFORMATION to 0 in API
MpInitLibGetProcessorInfo() of MpInitLibUp. This
commit use ZeroMem() to set all fileds in output
EFI_PROCESSOR_INFORMATION to 0 before StatusFlag
field is reassigned.

Previously EXTENDED_PROCESSOR_INFORMATION in the API
MpInitLibGetProcessorInfo() of MpInitLibUp is ignored.
In PEI/DXE MpInitLib, EXTENDED_PROCESSOR_INFORMATION
will be retrived when BIT24 of input ProcessorNumber
is set. This commit can avoid garbage in the output
structure in MpInitLibGetProcessorInfo() of MpInitLibUp.

Signed-off-by: Dun Tan <dun.tan@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Min Xu <min.m.xu@intel.com>
Message-Id: <20240108050804.1718-2-dun.tan@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
2024-01-09 16:31:57 +00:00
Tom Lendacky 3c5f9ac5c3 UefiCpuPkg/MpInitLib: Copy SEV-ES save area pointer during APIC ID sorting
With SEV-SNP, the SEV-ES save area for a vCPU should be unique to that
vCPU. After commit 3323359a81, the VMSA allocation was re-used, but when
sorting the CPUs by APIC ID, the save area was not updated to follow the
original CPU. Similar to the StartupApSignal address, the SevEsSaveArea
address should be updated when sorting the CPUs.

This does not cause an issue at this time because all APs are in HLT state
and then are (re)started at the same time, with the same VMSA contents.
However, this should be fixed to account for any change in future
behavior.

Fixes: 3323359a81 ("UefiCpuPkg/MpInitLib: Reuse VMSA allocation to ...")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
2023-11-28 11:07:59 +00:00
Yuanhao Xie cb3f41a937 UefiCpuPkg/MpInitLib: Enable execute disable bit.
This patch synchronizes the No-Execute bit in the IA32_EFER
register for the APs before the RestoreVolatileRegisters operation.

The commit 964a4f0, titled "Eliminate the second INIT-SIPI-SIPI
sequence," replaces the second INIT-SIPI-SIPI sequence with the BSP
calling the SwitchApContext function to initiate a specialized start-up
signal, waking up APs in the DXE instead of using INIT-SIPI-SIPI.

Due to this change, the logic for "Enable execute disable bit" in
MpFuncs.nasm is no longer executed. However, to ensure the proper setup
of the page table, it is necessary to synchronize the IA32_EFER.NXE for
APs before executing RestoreVolatileRegisters .

Based on SDM:
If IA32_EFER.NXE is set to 1, it signifies execute-disable, meaning
instruction fetches are not allowed from the 4-KByte page controlled by
this entry. Conversely, if it is set to 0, it is reserved.

Signed-off-by: Yuanhao Xie <yuanhao.xie@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek lersek@redhat.com
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
2023-11-27 05:21:45 +00:00
Yuanhao Xie 74c687cc2f UefiCpuPkg/MpInitLib: Wait for all APs to finish initialization
Aim:
- To solve the assertion that checks if CpuMpData->FinishedCount
equals (CpuMpData->CpuCount - 1). The assertion arises from a timing
discrepancy between the BSP's completion of startup signal checks and
the APs' incrementation of the FinishedCount.
- This patch also ensures that "finished" reporting from the APs is as
later as possible.

More specifially:

In the SwitchApContext() function, the BSP trigers
the startup signal and check whether the APs have received it. After
completing this check, the BSP then verifies if the FinishedCount is
equal to CpuCount-1.

On the AP side, upon receiving the startup signal, they invoke
SwitchContextPerAp() and increase the FinishedCount to indicate their
activation. However, even when all APs have received the startup signal,
they might not have finished incrementing the FinishedCount. This timing
gap results in the triggering of the assertion.

Solution:
Instead of assertion, use while loop to waits until all the APs have
incremented the FinishedCount.

Fixes: 964a4f032d

Signed-off-by: Yuanhao Xie <yuanhao.xie@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <20231025114216.2824-1-yuanhao.xie@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
2023-10-26 17:43:03 +00:00
YuanhaoXie eaffa1d7ff UefiCpuPkg:Wake up APs after power-up or RESET through SIPI.
The implementation of this new behavior aligns with the guidelines
outlined in the Intel SDM.

Following a power-up or RESET of an MP system, system hardware
dynamically selects one of the processors on the system bus as the BSP.
The remaining processors are designated as APs. The APs complete a
minimal self-configuration, then wait for a startup signal (a SIPI
message) from the BSP processor.

Additionally, the MP protocol is executed only after
a power-up or RESET. If the MP protocol has completed and a
BSP is chosen, subsequent INITs (either to a specific processor or
system wide) do not cause the MP protocol to be repeated. Instead, each
logical processor examines its BSP flag (in the IA32_APIC_BASE MSR) to
determine whether it should execute the BIOS boot-strap code (if it is
the BSP) or enter a wait-for-SIPI state (if it is an AP).

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Ray Ni <ray.ni@intel.com>
Signed-off-by: Yuanhao Xie <yuanhao.xie@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
2023-08-14 14:40:41 +00:00
YuanhaoXie c7a7f09c1d UefiCpuPkg: Decouple the SEV-ES functionality.
The purpose is to fix an issue where an exception occurs at the start
of the DXE phase by applying the following patch series on INTEL-based
systems.

UefiCpuPkg: Refactor the logic for placing APs in HltLoop.
UefiCpuPkg: Refactor the logic for placing APs in Mwait/Runloop.
UefiCpuPkg: Create MpHandOff.
UefiCpuPkg: ApWakeupFunction directly use CpuMpData.
UefiCpuPkg: Eliminate the second INIT-SIPI-SIPI sequence.

This series of patches makes changes to the way the APs are
initialized and woken up. It removes the 2nd time INIT-SIPI-SIPI and
introduces a special startup signal to wake up APs. These patches also
create a new HOB identified by the mMpHandOffGuid, which stores only the
 minimum information required from the PEI phase to the DXE phase.
As a result, the original HOB (mCpuInitMpLibHobGuid) is now used only
as a global variable in the PEI phase and is no longer necessary in the
DXE phase for INTEL-based systems. The AMD SEV-ES related code
still relies on the OldCpuMpData in the DXE phase.

This patch decouple the SEV-ES functionality of assigning CpuMpData to
OldCpuMpData->NewCpuMpData from the Intel logic.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Signed-off-by: Yuanhao Xie <yuanhao.xie@intel.com>
2023-07-27 17:10:13 +05:30
Xie, Yuanhao 964a4f032d UefiCpuPkg: Eliminate the second INIT-SIPI-SIPI sequence.
When both the PEI and DXE phases operate in the same execution
mode(32-bit/64-bit), the BSP send a special start-up signal during
the DXE phase to awaken the Application APs.

To eliminate the need for the INIT-SIPI-SIPI sequence at the beginning
of the DXE phase, the BSP call the SwitchApContext function to trigger
the special  start-up signal. By writing the specified
StartupSignalValue to the designated StartupSignalAddress, the BSP
wakes up the APs from mwait mode. Once the APs receive the
MP_HAND_OFF_SIGNAL value, they are awakened and proceed to execute the
SwitchContextPerAp procedure. They enter another while loop,
transitioning their context from the PEI phase to the DXE phase.

The original state transitions for an AP during the procedure are as
follows:
Idle ----> Ready ----> Busy ----> Idle
      [BSP]      [AP]      [AP]

Instead of init-sipi-sipi sequence, we make use of a
start-up signal to awaken the APs and transfer their context from
PEI to DXE. Consequently, APs, rather than the BSP, to set their state
to CpuStateReady.

Tested-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Yuanhao Xie <yuanhao.xie@intel.com>
2023-07-11 02:47:27 +00:00
Xie, Yuanhao 629c1dacc9 UefiCpuPkg: ApWakeupFunction directly use CpuMpData.
In the original design, once the APs finished executing their assembly
code and switched to executing C code, they would enter a continuous
loop within a function. In this function, they would collect CpuMpData
using the MP_CPU_EXCHANGE_INFO mechanism. However, in the updated
approach, CpuMpData can now be passed directly to the ApWakeUpFunction,
bypassing the need for MP_CPU_EXCHANGE_INFO. This modification is made
in preparation for eliminating the requirement of a second
INIT-SIPI-SIPI sequence in the DXE phase.

Tested-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Yuanhao Xie <yuanhao.xie@intel.com>
2023-07-11 02:47:27 +00:00
Xie, Yuanhao 8bb018afaf UefiCpuPkg: Create MpHandOff.
Initially, the purpose of the Hob was twofold: it served as a way to
transfer information from PEI to DXE. However, during the DXE phase,
only a few fields from the CPU_MP_DATA which collected in PEI phase were
 needed. A new Hob was specifically created to transfer information
 to the DXE phase. This new Hob contained only the essential fields
 required for reuse in DXE. For instance, instead of directly including
  the BspNumber in MpHandOff, the DXE phase introduced the use of
  GetBspNumber() to collect the BspNumber from ApicID and CpuCount.

The SaveCpuMpData() function was updated to construct the MP_HAND_OFF
Hob. Additionally, the function introduced the MP_HAND_OFF_SIGNAL,
which solely served the purpose of awakening the APs
and transitioning their context from PEI to DXE. The
WaitLoopExecutionMode field indicated whether the bit mode of PEI
matched that of DXE. Both of them were filled only if the ApLoopMode
was not ApInHltLoop. In the case of ApInHltLoop, it remained necessary
to wake up the APs using the init-sipi-sipi sequence. This improvement
 still allow INIT-SIPI-SIPI even APs are wait in Run/Mwait loop mode.

The function GetMpHandOffHob() was added to facilitate access to the
collected MpHandOff in the DXE phase. The CpuMpData in the DXE phase
was updated by gathering information from MpHandOff. Since MpHandOff
replaced the usage of OldCpuMpData and contained essential information
from the PEI phase to the DXE phase. AmdSevUpdateCpuMpData was included
to maintain the original implementation of AmdSev, ensuring that
OldCpuMpData->NewCpuMpData pointed to CpuMpData.

Tested-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Yuanhao Xie <yuanhao.xie@intel.com>
2023-07-11 02:47:27 +00:00
Xie, Yuanhao 243212b0d0 UefiCpuPkg: Refactor the logic for placing APs in Mwait/Runloop.
Refactor the logic for placing APs in
Mwait/Runloop into a separate function.

Tested-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Yuanhao Xie <yuanhao.xie@intel.com>
2023-07-11 02:47:27 +00:00
Xie, Yuanhao 88f436883b UefiCpuPkg: Refactor the logic for placing APs in HltLoop.
Refactor the logic for placing APs in HltLoop into a separate function.

Tested-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Yuanhao Xie <yuanhao.xie@intel.com>
2023-07-11 02:47:27 +00:00
Rebecca Cran 089013a697 UefiCpuPkg: Update code to be more C11 compliant by using __func__
__FUNCTION__ is a pre-standard extension that gcc and Visual C++ among
others support, while __func__ was standardized in C99.

Since it's more standard, replace __FUNCTION__ with __func__ throughout
UefiCpuPkg.

Signed-off-by: Rebecca Cran <rebecca@bsdio.com>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Sunil V L <sunilvl@ventanamicro.com>
2023-04-10 14:19:57 +00:00
Min M Xu a89f558d3c OvmfPkg/UefiCpuPkg/UefiPayloadPkg: Rename VmgExitLib to CcExitLib
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4123

VmgExitLib once was designed to provide interfaces to support #VC handler
and issue VMGEXIT instruction. After TDVF (enable TDX feature in OVMF) is
introduced, this library is updated to support #VE as well. Now the name
of VmgExitLib cannot reflect what the lib does.

This patch renames VmgExitLib to CcExitLib (Cc means Confidential
Computing). This is a simple renaming and there is no logic changes.
After renaming all the VmgExitLib related codes are updated with
CcExitLib. These changes are in OvmfPkg/UefiCpuPkg/UefiPayloadPkg.

Cc: Guo Dong <guo.dong@intel.com>
Cc: Sean Rhodes <sean@starlabs.systems>
Cc: James Lu <james.lu@intel.com>
Cc: Gua Guo <gua.guo@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: James Lu <james.lu@intel.com>
Reviewed-by: Gua Guo <gua.guo@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>
2022-11-14 04:55:34 +00:00
Yuanhao Xie 9ab2b34dd4 UefiCpuPkg: Use Top of each AP's stack to save CpuMpData
To remove the dependency of CPU register, 4/8 byte at the top of the
stack is occupied for CpuMpData. BIST information is also taken care
here. This modification is only for PEI phase, since in DXE phase
CpuMpData is accessed via global variable.

Signed-off-by: Yuanhao Xie <yuanhao.xie@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
2022-08-31 04:23:55 +00:00
Liu, Zhiguang d1abb876f4 UefiCpuPkg/MpInitLib: Simplify logic in SwitchBsp
When switch bsp, old bsp and new bsp put CR0/CR4 into stack, and put IDT
and GDT register into a structure. After they exchange their stack, they
restore these registers. This logic is now implemented by assembly code.
This patch aims to reuse (Save/Restore)VolatileRegisters function to
replace such assembly code for better code readability.

Cc: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Signed-off-by: Zhiguang Liu <zhiguang.liu@intel.com>
2022-08-31 04:23:55 +00:00
Ray Ni ccc269756f MpInitLib: Move the Above1Mb vector allocation to MpInitLibInitialize
The AP vector consists of 2 parts:
1. the initial 16-bit code that should be under 1MB and page aligned.
2. the 32-bit/64-bit code that can be anywhere in the memory with any
   alignment.

The need of part #2 is because the memory under 1MB is temporary
"stolen" for use and will "give" back after all AP wake up. The range
of memory is not marked as code page in page table. CPU may trigger
exception as soon as NX is enabled.

The part #2 memory allocation can be done in the MpInitLibInitialize.

Signed-off-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
2022-06-10 12:15:49 +00:00
Ray Ni 283ab9437a MpInitLib: Only allocate below 1MB memory for 16bit code
Today's implementation allocates below 1MB memory for the 16bit, 32bit
and 64bit code.

But it's not necessary since now the 32bit and 64bit code run at high
memory no matter in PEI and DXE phase.

The patch simplifies the logic to remove the code that handles the
case when WakeupBufferHigh is 0.
It also reduce the memory foot print under 1MB by allocating
memory for 16bit code only.

MP_CPU_EXCHANGE_INFO is still under 1MB which is immediate
after the 16bit code.

Signed-off-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
2022-06-10 12:15:49 +00:00
Ray Ni b4d7b9d2b5 MpInitLib: Put SEV logic in separate file
The patch does several simplifications:
1. Treat SwitchToRealProc as part of RendezvousFunnelProc.
   So the common logic in MpLib.c doesn't need to be aware of
   SwitchToRealProc.
   As a result, SwitchToRealSize/Offset are removed from
   MP_ASSEMBLY_ADDRESS_MAP.

2. Move SwitchToRealProc to AmdSev.nasm.
   All other assembly code in AmdSev.nasm is called through
   OneTimeCall.

Signed-off-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Michael Roth <michael.roth@amd.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
2022-06-10 12:15:49 +00:00
Ray Ni 54aeed7e00 MpInitLib: Allocate code buffer for PEI phase
Today's implementation assumes PEI phase runs at 32bit so
the execution-disable feature is not applicable.
It's not always TRUE.
The patch allocates 32bit&64bit code buffer for PEI phase as well.

Signed-off-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
2022-06-10 12:15:49 +00:00
Min M Xu b5cd30a79b UefiCpuPkg: Revert "UefiCpuPkg: Enable Tdx support in MpInitLib"
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3918

This reverts commit 88da06ca76.
This commit triggers the ASSERT in Non-Td guest.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
2022-05-11 08:40:53 +00:00
Min Xu 88da06ca76 UefiCpuPkg: Enable Tdx support in MpInitLib
RFC: https://bugzilla.tianocore.org/show_bug.cgi?id=3429

In TDVF BSP and APs are simplified. BSP is the vCPU-0, while the others
are treated as APs.

So MP intialization is rather simple. ApWorker is not supported, BSP is
always the working processor, while the APs are just in a
wait-for-precedure state.

Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>
2022-04-02 08:15:12 +00:00
Tom Lendacky 06544455d0 UefiCpuPkg/MpInitLib: Use SEV-SNP AP Creation NAE event to launch APs
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3275

Use the SEV-SNP AP Creation NAE event to create and launch APs under
SEV-SNP. This capability will be advertised in the SEV Hypervisor
Feature Support PCD (PcdSevEsHypervisorFeatures).

Cc: Michael Roth <michael.roth@amd.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Ray Ni <ray.ni@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
2021-12-09 06:28:10 +00:00
Michael Roth d4d7c9ad5f UefiCpuPkg/MpInitLib: use BSP to do extended topology check
During AP bringup, just after switching to long mode, APs will do some
cpuid calls to verify that the extended topology leaf (0xB) is available
so they can fetch their x2 APIC IDs from it. In the case of SEV-ES,
these cpuid instructions must be handled by direct use of the GHCB MSR
protocol to fetch the values from the hypervisor, since a #VC handler
is not yet available due to the AP's stack not being set up yet.

For SEV-SNP, rather than relying on the GHCB MSR protocol, it is
expected that these values would be obtained from the SEV-SNP CPUID
table instead. The actual x2 APIC ID (and 8-bit APIC IDs) would still
be fetched from hypervisor using the GHCB MSR protocol however, so
introducing support for the SEV-SNP CPUID table in that part of the AP
bring-up code would only be to handle the checks/validation of the
extended topology leaf.

Rather than introducing all the added complexity needed to handle these
checks via the CPUID table, instead let the BSP do the check in advance,
since it can make use of the #VC handler to avoid the need to scan the
SNP CPUID table directly, and add a flag in ExchangeInfo to communicate
the result of this check to APs.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Ray Ni <ray.ni@intel.com>
Suggested-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
2021-12-09 06:28:10 +00:00
Brijesh Singh 9c703bc0f1 UefiCpuPkg/MpLib: add support to register GHCB GPA when SEV-SNP is enabled
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3275

An SEV-SNP guest requires that the physical address of the GHCB must
be registered with the hypervisor before using it. See the GHCB
specification section 2.3.2 for more details.

Cc: Michael Roth <michael.roth@amd.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Ray Ni <ray.ni@Intel.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
2021-12-09 06:28:10 +00:00
Brijesh Singh b95908e043 UefiCpuPkg/MpInitLib: use PcdConfidentialComputingAttr to check SEV status
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3275

Previous commit introduced a generic confidential computing PCD that can
determine whether AMD SEV-ES is enabled. Update the MpInitLib to drop the
PcdSevEsIsEnabled in favor of PcdConfidentialComputingAttr.

Cc: Michael Roth <michael.roth@amd.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Ray Ni <ray.ni@intel.com>
Suggested-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
2021-12-09 06:28:10 +00:00
Brijesh Singh e2289d19d8 UefiCpuPkg/MpInitLib: move SEV specific routines in AmdSev.c
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3275

Move all the SEV specific function in AmdSev.c.

No functional change intended.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Michael Roth <michael.roth@amd.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Suggested-by: Jiewen Yao <Jiewen.yao@intel.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
2021-12-09 06:28:10 +00:00
Michael Kubacki 053e878bfb UefiCpuPkg: Apply uncrustify changes
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3737

Apply uncrustify changes to .c/.h files in the UefiCpuPkg package

Cc: Andrew Fish <afish@apple.com>
Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
2021-12-07 17:24:28 +00:00
Michael D Kinney 7c2a6033c1 UefiCpuPkg: Change complex DEBUG_CODE() to DEBUG_CODE_BEGIN/END()
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3767

Update use of DEBUG_CODE(Expression) if Expression is a complex code
block with if/while/for/case statements that use {}.

Cc: Andrew Fish <afish@apple.com>
Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Michael Kubacki <michael.kubacki@microsoft.com>
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
2021-12-07 17:24:28 +00:00
Michael D Kinney 4ec586b9f6 UefiCpuPkg: Change OPTIONAL keyword usage style
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3760

Update all use of ', OPTIONAL' to ' OPTIONAL,' for function params.

Cc: Andrew Fish <afish@apple.com>
Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Michael Kubacki <michael.kubacki@microsoft.com>
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
2021-12-07 17:24:28 +00:00
Lendacky, Thomas dbc22a1785 UefiCpuPkg/MpInitLib: Allocate a separate SEV-ES AP reset stack area
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3324

The SEV-ES stacks currently share a page with the reset code and data.
Separate the SEV-ES stacks from the reset vector code and data to avoid
possible stack overflows from overwriting the code and/or data.

When SEV-ES is enabled, invoke the GetWakeupBuffer() routine a second time
to allocate a new area, below the reset vector and data.

Both the PEI and DXE versions of GetWakeupBuffer() are changed so that
when PcdSevEsIsEnabled is true, they will track the previous reset buffer
allocation in order to ensure that the new buffer allocation is below the
previous allocation. When PcdSevEsIsEnabled is false, the original logic
is followed.

Fixes: 7b7508ad78
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Marvin Häuser <mhaeuser@posteo.de>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <3cae2ac836884b131725866264e0a0e1897052de.1621024125.git.thomas.lendacky@amd.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
2021-05-29 11:33:16 +00:00
Lendacky, Thomas 6933c78e4d UefiCpuPkg/MpInitLib: Properly cast from PCD to SEV-ES jump table pointer
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3385

A VS2012 build fails with a cast conversion warning when the SEV-ES work
area PCD is cast as a pointer to the SEV_ES_AP_JMP_FAR type.

When casting from a PCD value to a pointer, the cast should first be done
to a UINTN and then to the pointer. Update the code to perform a cast to
a UINTN before casting to a pointer to the SEV_ES_AP_JMP_FAR type.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Fixes: 7b7508ad78
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <c89bc819856d448360430c32cb3833a9667f987b.1620656694.git.thomas.lendacky@amd.com>
Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2021-05-11 17:45:40 +00:00
Ray Ni 030ba3097a UefiCpuPkg/MpInitLib: avoid printing debug messages in AP
MpInitLib contains a function MicrocodeDetect() which is called by
all threads as an AP procedure.
Today this function contains below code:

    if (CurrentRevision != LatestRevision) {
      AcquireSpinLock(&CpuMpData->MpLock);
      DEBUG ((
        EFI_D_ERROR,
        "Updated microcode signature [0x%08x] does not match \
        loaded microcode signature [0x%08x]\n",
        CurrentRevision, LatestRevision
        ));
      ReleaseSpinLock(&CpuMpData->MpLock);
    }

When the if-check is passed, the code may call into PEI services:
1. AcquireSpinLock
   When the PcdSpinTimeout is not 0, TimerLib
   GetPerformanceCounterProperties() is called. And some of the
   TimerLib implementations would get the information cached in
   HOB. But AP procedure cannot call PEI services to retrieve the
   HOB list.

2. DEBUG
   Certain DebugLib relies on ReportStatusCode services and the
   ReportStatusCode PPI is retrieved through the PEI services.
   DebugLibSerialPort should be used.
   But when SerialPortLib is implemented to depend on PEI services,
   even using DebugLibSerialPort can still cause AP calls PEI
   services resulting hang.

It causes a lot of debugging effort on the platform side.

There are 2 options to fix the problem:
1. make sure platform DSC chooses the proper DebugLib and set the
   PcdSpinTimeout to 0. So that AcquireSpinLock and DEBUG don't call
   PEI services.
2. remove the AcquireSpinLock and DEBUG call from the procedure.

Option #2 is preferred because it's not practical to ask every
platform DSC to be written properly.

Following option #2, there are two sub-options:
2.A. Just remove the if-check.
2.B. Capture the CurrentRevision and ExpectedRevision in the memory
     for each AP and print them together from BSP.

The patch follows option 2.B.

Signed-off-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
2021-03-17 12:39:31 +00:00
Ray Ni 8c61f1934d UefiCpuPkg/MpInitLib: Remove unused Lock from MP_CPU_EXCHANGE_INFO
The Lock is no longer needed since "LOCK XADD" was used in
MpFuncs.nasm for ApIndex atomic increment.

Signed-off-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
2021-03-08 02:22:37 +00:00
Ray Ni c6be6dab9c UefiCpuPkg/MpInitLib: Don't increase CpuCount in ApWakeupFunction
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3179

When BSP first time wakes all APs, each AP atomically increases
CpuMpData->CpuCount and CpuMpData->FinishedCount.

Each AP atomically increases CpuMpData->NumApsExecuting
in early assembly code and decreases it before it enters to HLT or
MWAIT state.

Putting them together, the 3 variables are changed in the following order:
1. NumApsExecuting++ // in assembly
2. CpuCpunt++
4. FinishedCount++
3. NumApsExecuting-- // in C

BSP waits for a certain timeout and then polls NumApsExecuting
until it drops to zero. It assumes all APs are waken up concurrently
and NumApsExecuting only drops to zero when all APs have checked in.

Then it additionally waits for FinishedCount == CpuCount - 1. (FinishedCount doesn't include BSP while CpuCount includes BSP.)

There is no need to additionally wait for
FinishedCount == CpuCount - 1 because when NumApsExecuting == 0,
the number of increament of FinishedCount and CpuCount should equal.

This patch simplifies the code to remove "CpuCount++" in
ApWakeupFunction() and
assigns FinishedCount + 1 to CpuCount after WakeUpAP().

Signed-off-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
2021-01-29 03:09:35 +00:00
Michael D Kinney 1c5c7bcd1d UefiCpuPkg/Library/MpInitLib: Fix AP VolatileRegisters race condition
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3182

Fix the order of operations in ApWakeupFunction() when PcdCpuApLoopMode
is set to HLT mode that uses INIT-SIPI-SIPI to wake APs.  In this mode,
volatile state is restored and saved each time a INIT-SIPI-SIPI is sent
to an AP to request a function to be executed on the AP.  When the
function is completed the volatile state of the AP is saved.  However,
the counters NumApsExecuting and FinishedCount are updated before
the volatile state is saved.  This allows for a race condition window
for the BSP that is waiting on these counters to request a new
INIT-SIPI-SIPI before all the APs have completely saved their volatile
state.  The fix is to save the AP volatile state before updating the
NumApsExecuting and FinishedCount counters.

Cc: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
2021-01-26 03:18:40 +00:00
Tom Lendacky d150439b72 UefiCpuPkg/MpInitLib: For SEV-ES guest, set stack based on processor number
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3008

Set the SEV-ES reset stack address for an AP based on the processor number
instead of the APIC ID in case the APIC IDs are not zero-based and densely
packed/enumerated. This will ensure an AP reset stack address does not get
set outside of the AP reset stack memory allocation.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Acked-by: Ray Ni <ray.ni@intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <24866de07d2a954dec71df70972f1851273020d8.1604685192.git.thomas.lendacky@amd.com>
2020-11-10 19:07:55 +00:00
Tom Lendacky 1b0db1ec87 UefiCpuPkg, OvmfPkg: Disable interrupts when using the GHCB
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3008

The QemuFlashPtrWrite() flash services runtime uses the GHCB and VmgExit()
directly to perform the flash write when running as an SEV-ES guest. If an
interrupt arrives between VmgInit() and VmgExit(), the Dr7 read in the
interrupt handler will generate a #VC, which can overwrite information in
the GHCB that QemuFlashPtrWrite() has set. This has been seen with the
timer interrupt firing and the CpuExceptionHandlerLib library code,
UefiCpuPkg/Library/CpuExceptionHandlerLib/X64/
  Xcode5ExceptionHandlerAsm.nasm and
  ExceptionHandlerAsm.nasm
reading the Dr7 register while QemuFlashPtrWrite() is using the GHCB. In
general, it is necessary to protect the GHCB whenever it is used, not just
in QemuFlashPtrWrite().

Disable interrupts around the usage of the GHCB by modifying the VmgInit()
and VmgDone() interfaces:
- VmgInit() will take an extra parameter that is a pointer to a BOOLEAN
  that will hold the interrupt state at the time of invocation. VmgInit()
  will get and save this interrupt state before updating the GHCB.
- VmgDone() will take an extra parameter that is used to indicate whether
  interrupts are to be (re)enabled. Before exiting, VmgDone() will enable
  interrupts if that is requested.

Fixes: 437eb3f7a8
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Acked-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <c326a4fd78253f784b42eb317589176cf7d8592a.1604685192.git.thomas.lendacky@amd.com>
2020-11-10 19:07:55 +00:00
Tom Lendacky 93edd1887e UefiCpuPkg/MpInitLib: Reduce reset vector memory pressure
The AP reset vector stack allocation is only required if running as an
SEV-ES guest. Since the reset vector allocation is below 1MB in memory,
eliminate the requirement for bare-metal systems and non SEV-ES guests
to allocate the extra stack area, which can be large if the
PcdCpuMaxLogicalProcessorNumber value is large, and also remove the
CPU_STACK_ALIGNMENT alignment.

Fixes: 7b7508ad78 ("UefiCpuPkg: Allow AP booting under SEV-ES")
Cc: Garrett Kirkendall <garrett.kirkendall@amd.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <21345cdbc906519558202b3851257ca07b9239ba.1600884239.git.thomas.lendacky@amd.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
[lersek@redhat.com: supply missing space character after "PcdGet32"]
2020-10-19 21:47:21 +00:00
Tom Lendacky 48a83481d2 UefiCpuPkg/MpInitLib: Always initialize the DoDecrement variable
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2901

The DoDecrement variable in ApWakeupFunction () wasn't always being
initialized. Update the code to always fully initialize it.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <76a9f18992475b915e5f8457704676067210cacf.1597935198.git.thomas.lendacky@amd.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Tested-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2020-08-24 19:02:40 +00:00
Tom Lendacky 7b7508ad78 UefiCpuPkg: Allow AP booting under SEV-ES
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198

Typically, an AP is booted using the INIT-SIPI-SIPI sequence. This
sequence is intercepted by the hypervisor, which sets the AP's registers
to the values requested by the sequence. At that point, the hypervisor can
start the AP, which will then begin execution at the appropriate location.

Under SEV-ES, AP booting presents some challenges since the hypervisor is
not allowed to alter the AP's register state. In this situation, we have
to distinguish between the AP's first boot and AP's subsequent boots.

First boot:
 Once the AP's register state has been defined (which is before the guest
 is first booted) it cannot be altered. Should the hypervisor attempt to
 alter the register state, the change would be detected by the hardware
 and the VMRUN instruction would fail. Given this, the first boot for the
 AP is required to begin execution with this initial register state, which
 is typically the reset vector. This prevents the BSP from directing the
 AP startup location through the INIT-SIPI-SIPI sequence.

 To work around this, the firmware will provide a build time reserved area
 that can be used as the initial IP value. The hypervisor can extract this
 location value by checking for the SEV-ES reset block GUID that must be
 located 48-bytes from the end of the firmware. The format of the SEV-ES
 reset block area is:

   0x00 - 0x01 - SEV-ES Reset IP
   0x02 - 0x03 - SEV-ES Reset CS Segment Base[31:16]
   0x04 - 0x05 - Size of the SEV-ES reset block
   0x06 - 0x15 - SEV-ES Reset Block GUID
                   (00f771de-1a7e-4fcb-890e-68c77e2fb44e)

   The total size is 22 bytes. Any expansion to this block must be done
   by adding new values before existing values.

 The hypervisor will use the IP and CS values obtained from the SEV-ES
 reset block to set as the AP's initial values. The CS Segment Base
 represents the upper 16 bits of the CS segment base and must be left
 shifted by 16 bits to form the complete CS segment base value.

 Before booting the AP for the first time, the BSP must initialize the
 SEV-ES reset area. This consists of programming a FAR JMP instruction
 to the contents of a memory location that is also located in the SEV-ES
 reset area. The BSP must program the IP and CS values for the FAR JMP
 based on values drived from the INIT-SIPI-SIPI sequence.

Subsequent boots:
 Again, the hypervisor cannot alter the AP register state, so a method is
 required to take the AP out of halt state and redirect it to the desired
 IP location. If it is determined that the AP is running in an SEV-ES
 guest, then instead of calling CpuSleep(), a VMGEXIT is issued with the
 AP Reset Hold exit code (0x80000004). The hypervisor will put the AP in
 a halt state, waiting for an INIT-SIPI-SIPI sequence. Once the sequence
 is recognized, the hypervisor will resume the AP. At this point the AP
 must transition from the current 64-bit long mode down to 16-bit real
 mode and begin executing at the derived location from the INIT-SIPI-SIPI
 sequence.

 Another change is around the area of obtaining the (x2)APIC ID during AP
 startup. During AP startup, the AP can't take a #VC exception before the
 AP has established a stack. However, the AP stack is set by using the
 (x2)APIC ID, which is obtained through CPUID instructions. A CPUID
 instruction will cause a #VC, so a different method must be used. The
 GHCB protocol supports a method to obtain CPUID information from the
 hypervisor through the GHCB MSR. This method does not require a stack,
 so it is used to obtain the necessary CPUID information to determine the
 (x2)APIC ID.

The new 16-bit protected mode GDT entry is used in order to transition
from 64-bit long mode down to 16-bit real mode.

A new assembler routine is created that takes the AP from 64-bit long mode
to 16-bit real mode.  This is located under 1MB in memory and transitions
from 64-bit long mode to 32-bit compatibility mode to 16-bit protected
mode and finally 16-bit real mode.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
2020-08-17 02:46:39 +00:00
Tom Lendacky e88a5b9833 UefiCpuPkg/MpInitLib: Add CPU MP data flag to indicate if SEV-ES is enabled
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198

When starting APs in an SMP configuration, the AP needs to know if it is
running as an SEV-ES guest in order to assign a GHCB page.

Add a field to the CPU_MP_DATA structure that will indicate if SEV-ES is
enabled. This new field is set during MP library initialization with the
PCD value PcdSevEsIsEnabled. This flag can then be used to determine if
SEV-ES is enabled.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
2020-08-17 02:46:39 +00:00
Kirkendall, Garrett df667535ed UefiCpuPkg: Move StandardSignatureIsAuthenticAMD to BaseUefiCpuLib
Refactor StandardSignatureIsAuthenticAMD into BaseUefiCpuLib from
separate copies in BaseXApicLib, BaseXApicX2ApicLib, and MpInitLib.
This allows for future use of StandarSignatureIsAuthinticAMD without
creating more instances in other modules.

This function allows IA32/X64 code to determine if it is running on an
AMD brand processor.

UefiCpuLib is already included directly or indirectly in all modified
modules.  Complete move is made in this change.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Garrett Kirkendall <garrett.kirkendall@amd.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Message-Id: <20200622131825.1352-4-Garrett.Kirkendall@amd.com>
2020-07-07 23:25:16 +00:00