Re: UefiCpuPkg/MpInitLib: Fix S3 resume hang issue.

[Laszlo Ersek <lersek@redhat.com>]

Hi,

On 07/18/18 07:10, Eric Dong wrote:
> 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>
> ---
>  UefiCpuPkg/Library/MpInitLib/MpLib.c          | 16 ++++-
>  UefiCpuPkg/Library/MpInitLib/MpLib.h          |  9 +++
>  UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf |  4 ++
>  UefiCpuPkg/Library/MpInitLib/PeiMpLib.c       | 89 +++++++++++++++++++++++++++
>  4 files changed, 116 insertions(+), 2 deletions(-)

I see this patch is already committed (58942277bcbf); I have two
comments in retrospect:

> diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c b/UefiCpuPkg/Library/MpInitLib/MpLib.c
> index 722db2a01f..e5c701ddeb 100644
> --- a/UefiCpuPkg/Library/MpInitLib/MpLib.c
> +++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c
> @@ -985,13 +985,15 @@ WakeUpAP (
>    CpuMpData->FinishedCount = 0;
>    ResetVectorRequired = FALSE;
>
> -  if (CpuMpData->ApLoopMode == ApInHltLoop ||
> +  if (CpuMpData->WakeUpByInitSipiSipi ||
>        CpuMpData->InitFlag   != ApInitDone) {
>      ResetVectorRequired = TRUE;
>      AllocateResetVector (CpuMpData);
>      FillExchangeInfoData (CpuMpData);
>      SaveLocalApicTimerSetting (CpuMpData);
> -  } else if (CpuMpData->ApLoopMode == ApInMwaitLoop) {
> +  }
> +
> +  if (CpuMpData->ApLoopMode == ApInMwaitLoop) {
>      //
>      // Get AP target C-state each time when waking up AP,
>      // for it maybe updated by platform again
> @@ -1076,6 +1078,13 @@ WakeUpAP (
>    if (ResetVectorRequired) {
>      FreeResetVector (CpuMpData);
>    }
> +
> +  //
> +  // After one round of Wakeup Ap actions, need to re-sync ApLoopMode with
> +  // WakeUpByInitSipiSipi flag. WakeUpByInitSipiSipi flag maybe changed by
> +  // S3SmmInitDone Ppi.
> +  //
> +  CpuMpData->WakeUpByInitSipiSipi = (CpuMpData->ApLoopMode == ApInHltLoop);
>  }
>
>  /**
> @@ -1648,6 +1657,9 @@ MpInitLibInitialize (
>    //
>    CpuMpData->ApLoopMode = ApLoopMode;
>    DEBUG ((DEBUG_INFO, "AP Loop Mode is %d\n", CpuMpData->ApLoopMode));
> +
> +  CpuMpData->WakeUpByInitSipiSipi = (CpuMpData->ApLoopMode == ApInHltLoop);
> +
>    //
>    // Set up APs wakeup signal buffer
>    //
> diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.h b/UefiCpuPkg/Library/MpInitLib/MpLib.h
> index 6958080ac1..9d0b866d09 100644
> --- a/UefiCpuPkg/Library/MpInitLib/MpLib.h
> +++ b/UefiCpuPkg/Library/MpInitLib/MpLib.h
> @@ -250,6 +250,15 @@ struct _CPU_MP_DATA {
>    UINT32                         ProcessorFlags;
>    UINT64                         MicrocodeDataAddress;
>    UINT32                         MicrocodeRevision;
> +
> +  //
> +  // Whether need to use Init-Sipi-Sipi to wake up the APs.
> +  // Two cases need to set this value to TRUE. One is in HLT
> +  // loop mode, the other is resume from S3 which loop mode
> +  // will be hardcode change to HLT mode by PiSmmCpuDxeSmm
> +  // driver.
> +  //
> +  BOOLEAN                        WakeUpByInitSipiSipi;
>  };
>
>  extern EFI_GUID mCpuInitMpLibHobGuid;
> diff --git a/UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf b/UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf
> index fa84e392af..43a3b3b036 100644
> --- a/UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf
> +++ b/UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf
> @@ -44,6 +44,7 @@
>  [Packages]
>    MdePkg/MdePkg.dec
>    UefiCpuPkg/UefiCpuPkg.dec
> +  MdeModulePkg/MdeModulePkg.dec
>
>  [LibraryClasses]
>    BaseLib
> @@ -54,6 +55,7 @@
>    CpuLib
>    UefiCpuLib
>    SynchronizationLib
> +  PeiServicesLib
>
>  [Pcd]
>    gUefiCpuPkgTokenSpaceGuid.PcdCpuMaxLogicalProcessorNumber        ## CONSUMES
> @@ -64,3 +66,5 @@
>    gUefiCpuPkgTokenSpaceGuid.PcdCpuApLoopMode                       ## CONSUMES
>    gUefiCpuPkgTokenSpaceGuid.PcdCpuApTargetCstate                   ## SOMETIMES_CONSUMES
>
> +[Guids]
> +  gEdkiiS3SmmInitDoneGuid
> \ No newline at end of file
> diff --git a/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c b/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c
> index 92f28681e4..06d966b227 100644
> --- a/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c
> +++ b/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c
> @@ -13,6 +13,87 @@
>  **/
>
>  #include "MpLib.h"
> +#include <Library/PeiServicesLib.h>
> +#include <Guid/S3SmmInitDone.h>
> +
> +/**
> +  S3 SMM Init Done notification function.
> +
> +  @param  PeiServices      Indirect reference to the PEI Services Table.
> +  @param  NotifyDesc       Address of the notification descriptor data structure.
> +  @param  InvokePpi        Address of the PPI that was invoked.
> +
> +  @retval EFI_SUCCESS      The function completes successfully.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +NotifyOnS3SmmInitDonePpi (
> +  IN  EFI_PEI_SERVICES                              **PeiServices,
> +  IN  EFI_PEI_NOTIFY_DESCRIPTOR                     *NotifyDesc,
> +  IN  VOID                                          *InvokePpi
> +  );
> +
> +
> +//
> +// Global function
> +//
> +EFI_PEI_NOTIFY_DESCRIPTOR        mS3SmmInitDoneNotifyDesc = {
> +  EFI_PEI_PPI_DESCRIPTOR_NOTIFY_CALLBACK | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST,
> +  &gEdkiiS3SmmInitDoneGuid,
> +  NotifyOnS3SmmInitDonePpi
> +};
> +
> +/**
> +  The function prototype for invoking a function on an Application Processor.
> +
> +  This definition is used by the UEFI MP Serices Protocol, and the
> +  PI SMM System Table.
> +
> +  @param[in,out] Buffer  The pointer to private data buffer.
> +**/
> +VOID
> +EmptyApProcedure (
> +  IN OUT VOID * Buffer
> +  )
> +{
> +}
> +

(1) This function seems useless -- can you please submit a patch to
remove it?

> +/**
> +  S3 SMM Init Done notification function.
> +
> +  @param  PeiServices      Indirect reference to the PEI Services Table.
> +  @param  NotifyDesc       Address of the notification descriptor data structure.
> +  @param  InvokePpi        Address of the PPI that was invoked.
> +
> +  @retval EFI_SUCCESS      The function completes successfully.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +NotifyOnS3SmmInitDonePpi (
> +  IN  EFI_PEI_SERVICES                              **PeiServices,
> +  IN  EFI_PEI_NOTIFY_DESCRIPTOR                     *NotifyDesc,
> +  IN  VOID                                          *InvokePpi
> +  )
> +{
> +  CPU_MP_DATA     *CpuMpData;
> +
> +  CpuMpData = GetCpuMpData ();
> +
> +  //
> +  // PiSmmCpuDxeSmm driver hardcode change the loop mode to HLT mode.
> +  // So in this notify function, code need to check the current loop
> +  // mode, if it is not HLT mode, code need to change loop mode back
> +  // to the original mode.
> +  //
> +  if (CpuMpData->ApLoopMode != ApInHltLoop) {
> +    CpuMpData->WakeUpByInitSipiSipi = TRUE;
> +  }
> +
> +  return EFI_SUCCESS;
> +}
> +
>
>  /**
>    Enable Debug Agent to support source debugging on AP function.
> @@ -240,7 +321,15 @@ InitMpGlobalData (
>    IN CPU_MP_DATA               *CpuMpData
>    )
>  {
> +  EFI_STATUS  Status;
> +
>    SaveCpuMpData (CpuMpData);
> +
> +  ///
> +  /// Install Notify
> +  ///
> +  Status = PeiServicesNotifyPpi (&mS3SmmInitDoneNotifyDesc);
> +  ASSERT_EFI_ERROR (Status);
>  }
>
>  /**
>

(2) Because OVMF uses the "UefiCpuPkg.dec" default for PcdCpuApLoopMode
(value 1, "Place AP in the Hlt-Loop state"), this patch should mostly be
a no-op for OVMF; WakeUpByInitSipiSipi is always TRUE (and
NotifyOnS3SmmInitDonePpi() basically does nothing).

So, I regression-tested this change, and it's fine. I see that the PPI
notify is registered, and then called, but there's no other change to S3
resume behavior:

> Loading PEIM at 0x0000086FCC0 EntryPoint=0x00000875367 CpuMpPei.efi
> AP Loop Mode is 1
> WakeupBufferStart = 9F000, WakeupBufferSize = 0
> TimedWaitForApFinish: reached FinishedApLimit=7 in 0 microseconds
> APIC MODE is 1
> MpInitLib: Find 8 processors in system.
> Register PPI Notify: [EdkiiS3SmmInitDone]
> Does not find any stored CPU BIST information from PPI!
>   APICID - 0x00000000, BIST - 0x00000000
>   APICID - 0x00000001, BIST - 0x00000000
>   APICID - 0x00000002, BIST - 0x00000000
>   APICID - 0x00000003, BIST - 0x00000000
>   APICID - 0x00000004, BIST - 0x00000000
>   APICID - 0x00000005, BIST - 0x00000000
>   APICID - 0x00000006, BIST - 0x00000000
>   APICID - 0x00000007, BIST - 0x00000000
> Install PPI: [EfiSecPlatformInformation2Ppi]
> Install PPI: [EfiPeiMpServicesPpi]
> [...]
> Call AsmDisablePaging64() to return to S3 Resume in PEI Phase
> S3ResumeExecuteBootScript()
> Close all SMRAM regions before executing boot script
> Lock all SMRAM regions before executing boot script
> Signal S3SmmInitDone
> Install PPI: [EdkiiS3SmmInitDone]
> Notify: PPI Guid: [EdkiiS3SmmInitDone], Peim notify entry point: 87674B
> Signal [EdkiiS3SmmInitDone] to SMM - Enter
> Locate Smm Communicate Ppi failed (Not Found)!
> PeiS3ResumeState - 7EF62118
> Enable X64 and transfer control to Standalone Boot Script Executor
> [...]

Regression-tested-by: Laszlo Ersek <lersek@redhat.com>

Thanks
Laszlo