Re: [edk2-devel] [PATCH v9 0/6] Simplify SMM Relocation Process

["Ni, Ray" <ray.ni@intel.com>]

Mike, it can wait.

> -----Original Message-----
> From: Kinney, Michael D <michael.d.kinney@intel.com>
> Sent: Monday, February 20, 2023 10:37 AM
> To: devel@edk2.groups.io; Wu, Jiaxin <jiaxin.wu@intel.com>
> Cc: Dong, Eric <eric.dong@intel.com>; Ni, Ray <ray.ni@intel.com>; Zeng, Star
> <star.zeng@intel.com>; Laszlo Ersek <lersek@redhat.com>; Gerd Hoffmann
> <kraxel@redhat.com>; Kumar, Rahul R <rahul.r.kumar@intel.com>; Kinney,
> Michael D <michael.d.kinney@intel.com>
> Subject: RE: [edk2-devel] [PATCH v9 0/6] Simplify SMM Relocation Process
> 
> Is this for the edk2-stable202303?  Or can it wait to be merged after the
> release?
> 
> Thanks,
> 
> Mike
> 
> > -----Original Message-----
> > From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Wu,
> Jiaxin
> > Sent: Sunday, February 19, 2023 5:07 PM
> > To: devel@edk2.groups.io; Wu, Jiaxin <jiaxin.wu@intel.com>
> > Cc: Dong, Eric <eric.dong@intel.com>; Ni, Ray <ray.ni@intel.com>; Zeng,
> Star <star.zeng@intel.com>; Laszlo Ersek
> > <lersek@redhat.com>; Gerd Hoffmann <kraxel@redhat.com>; Kumar,
> Rahul R <rahul.r.kumar@intel.com>
> > Subject: Re: [edk2-devel] [PATCH v9 0/6] Simplify SMM Relocation Process
> >
> > Any more comments to patch series? If no objection, Ray, please help
> merge the patches.
> >
> > Thanks,
> > Jiaxin
> >
> >
> >
> > > -----Original Message-----
> > > From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Wu,
> Jiaxin
> > > Sent: Thursday, February 16, 2023 2:16 PM
> > > To: devel@edk2.groups.io
> > > Cc: Dong, Eric <eric.dong@intel.com>; Ni, Ray <ray.ni@intel.com>; Zeng,
> Star
> > > <star.zeng@intel.com>; Laszlo Ersek <lersek@redhat.com>; Gerd
> Hoffmann
> > > <kraxel@redhat.com>; Kumar, Rahul R <rahul.r.kumar@intel.com>
> > > Subject: [edk2-devel] [PATCH v9 0/6] Simplify SMM Relocation Process
> > >
> > > Existing SMBASE Relocation is in the PiSmmCpuDxeSmm driver, which
> > > will relocate the SMBASE of each processor by setting the SMBASE
> > > field in the saved state map (at offset 7EF8h) to a new value.
> > > The RSM instruction reloads the internal SMBASE register with the
> > > value in SMBASE field when each time it exits SMM. All subsequent
> > > SMI requests will use the new SMBASE to find the starting address
> > > for the SMI handler (at SMBASE + 8000h).
> > >
> > > Due to the default SMBASE for all x86 processors is 0x30000, the
> > > APs' 1st SMI for rebase has to be executed one by one to avoid
> > > the processors over-writing each other's SMM Save State Area (see
> > > existing SmmRelocateBases() function), which means the next AP has
> > > to wait for the previous AP to finish its 1st SMI, then it can call
> > > into its 1st SMI for rebase via Smi Ipi command, thus leading the
> > > existing SMBASE Relocation has to be running in series. Besides, it
> > > needs very complex code to handle the AP exit semaphore
> > > (mRebased[Index]), which will hook return address of SMM Save State
> > > so that semaphore code can be executed immediately after AP exits
> > > SMM for SMBASE relocation (see existing SemaphoreHook() function).
> > >
> > > This series is to add the new SMM Base HOB for any PEI module to do
> > > the SmBase relocation ahead of PiSmmCpuDxeSmm driver and store the
> > > relocated SmBase address in array for each Processors. When the
> > > SMBASE relocation happens in a PEI module, the PEI module shall
> > > produce the SMM_BASE_HOB in HOB database which tells the
> > > PiSmmCpuDxeSmm driver (runs at a later phase) about the new SMBASE
> > > for each CPU thread. PiSmmCpuDxeSmm driver installs the SMI handler
> > > at the SMM_BASE_HOB.SmBase[Index]+0x8000 for processor Index.
> When
> > > the HOB doesn't exist, PiSmmCpuDxeSmm driver shall relocate and
> > > program the new SMBASE itself (keep existing SMBASE Relocation way).
> > >
> > > With SMM Base Hob support, PiSmmCpuDxeSmm does not need the
> RSM
> > > instruction to do the SMBASE Relocation. SMBASE Register for each
> > > processors have already been programmed and all SMBASE address have
> > > recorded in SMM Base Hob. So the same default SMBASE Address
> > > (0x30000) will not be used, thus the processors over-writing each
> > > other's SMM Save State Area will not happen in PiSmmCpuDxeSmm
> driver.
> > > This way makes the first SMI init can be executed in parallel and save
> > > boot time on multi-core system. Besides, Semaphore Hook code logic
> > > is also not required, which will greatly simplify the SMBASE
> > > Relocation flow.
> > >
> > > Note:
> > > This is the new way that firmware can program the SMBASE
> > > independently of the RSM instruction. The PEI code performing
> > > this logic will not be open sourced, similarly to other things
> > > that are kept binary-only in the FSP. Due to the register
> > > difference in different vender, and it has not been documented
> > > in the Intel SDM yet, we need a new binary-only interface for
> > > SMM Base HOB.
> > >
> > > Cc: Eric Dong <eric.dong@intel.com>
> > > Cc: Ray Ni <ray.ni@intel.com>
> > > Cc: Zeng Star <star.zeng@intel.com>
> > > Cc: Laszlo Ersek <lersek@redhat.com>
> > > Cc: Gerd Hoffmann <kraxel@redhat.com>
> > > Cc: Rahul Kumar <rahul1.kumar@intel.com>
> > > Signed-off-by: Jiaxin Wu <jiaxin.wu@intel.com>
> > >
> > > Jiaxin Wu (6):
> > >   UefiCpuPkg/PiSmmCpuDxeSmm: Fix invalid InitializeMpSyncData call
> > >   UefiCpuPkg/PiSmmCpuDxeSmm: Replace mIsBsp by mBspApicId check
> > >   UefiCpuPkg/SmmBaseHob.h: Add SMM Base HOB Data
> > >   UefiCpuPkg/PiSmmCpuDxeSmm: Consume SMM Base Hob for SmBase
> info
> > >   UefiCpuPkg/SmmCpuFeaturesLib: Skip SMBASE configuration
> > >   OvmfPkg/SmmCpuFeaturesLib: Check SmBase relocation supported or
> not
> > >
> > >  .../Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.c  |  10 +-
> > >  .../SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf        |   6 +-
> > >  UefiCpuPkg/Include/Guid/SmmBaseHob.h               |  75 ++++++++
> > >  .../Library/SmmCpuFeaturesLib/CpuFeaturesLib.h     |   2 +
> > >  .../SmmCpuFeaturesLib/IntelSmmCpuFeaturesLib.c     |  25 ++-
> > >  .../SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf        |   6 +-
> > >  .../SmmCpuFeaturesLib/SmmCpuFeaturesLibStm.inf     |   3 +-
> > >  UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmStm.c      |   3 +-
> > >  .../StandaloneMmCpuFeaturesLib.inf                 |   6 +-
> > >  UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c                  |  31 +++-
> > >  UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c              |  25 ++-
> > >  UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c         | 193
> > > ++++++++++++++++-----
> > >  UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h         |  26 ++-
> > >  UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf       |   3 +-
> > >  UefiCpuPkg/UefiCpuPkg.dec                          |   5 +-
> > >  15 files changed, 356 insertions(+), 63 deletions(-)
> > >  create mode 100644 UefiCpuPkg/Include/Guid/SmmBaseHob.h
> > >
> > > --
> > > 2.16.2.windows.1
> > >
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> >