Re: [edk2-devel] [PATCH 33/35] StandaloneMmPkg/Core: stop abusing EFI_HANDLE for FwVolHeader tracking

["Laszlo Ersek" <lersek@redhat.com>]

Achin, Jiewen, Supreeth,

can one of you guys please review this patch?

Thanks
Laszlo

On 09/17/19 21:49, Laszlo Ersek wrote:
> The FvHasBeenProcessed() and FvIsBeingProcesssed() functions make sure
> that every firmware volume is processed only once (every driver in every
> firmware volume should be discovered only once). For this, the functions
> use a linked list.
> 
> In MdeModulePkg's DXE Core and SMM Core, the key used for identifying
> those firmware volumes that have been processed is the EFI_HANDLE on which
> the DXE or SMM firmware volume protocol is installed. In the
> StandaloneMmPkg core however, the key is the address of the firmware
> volume header; that is, it has type (EFI_FIRMWARE_VOLUME_HEADER*).
> 
> (EFI_FIRMWARE_VOLUME_HEADER*) has nothing to do with EFI_HANDLE.
> EFI_HANDLE just happens to be specified as (VOID*), and therefore the
> conversion between (EFI_FIRMWARE_VOLUME_HEADER*) and EFI_HANDLE is silent.
> 
> (The FvHasBeenProcessed() and FvIsBeingProcesssed() functions were likely
> copied verbatim from MdeModulePkg's DXE Core and/or the SMM Core, and not
> flagged by the compiler in StandaloneMmPkg due to UEFI regrettably
> specifying EFI_HANDLE as (VOID*), thereby enabling the above implicit
> conversion.)
> 
> We should not exploit this circumstance. Represent the key type faithfully
> instead.
> 
> This is a semantic fix; there is no change in operation.
> 
> Cc: Achin Gupta <achin.gupta@arm.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Supreeth Venkatesh <supreeth.venkatesh@arm.com>
> Signed-off-by: Laszlo Ersek <lersek@redhat.com>
> ---
> 
> Notes:
>     build-tested only
> 
>  StandaloneMmPkg/Core/StandaloneMmCore.h |  2 +-
>  StandaloneMmPkg/Core/Dispatcher.c       | 80 +++++++++++---------
>  StandaloneMmPkg/Core/FwVol.c            | 16 ++--
>  3 files changed, 52 insertions(+), 46 deletions(-)
> 
> diff --git a/StandaloneMmPkg/Core/StandaloneMmCore.h b/StandaloneMmPkg/Core/StandaloneMmCore.h
> index dcf91bc5e916..23ddbe169faf 100644
> --- a/StandaloneMmPkg/Core/StandaloneMmCore.h
> +++ b/StandaloneMmPkg/Core/StandaloneMmCore.h
> @@ -67,7 +67,7 @@ typedef struct {
>  
>    LIST_ENTRY                      ScheduledLink;    // mScheduledQueue
>  
> -  EFI_HANDLE                      FvHandle;
> +  EFI_FIRMWARE_VOLUME_HEADER      *FwVolHeader;
>    EFI_GUID                        FileName;
>    VOID                            *Pe32Data;
>    UINTN                           Pe32DataSize;
> diff --git a/StandaloneMmPkg/Core/Dispatcher.c b/StandaloneMmPkg/Core/Dispatcher.c
> index 3788389f95ed..9853445a64a1 100644
> --- a/StandaloneMmPkg/Core/Dispatcher.c
> +++ b/StandaloneMmPkg/Core/Dispatcher.c
> @@ -5,7 +5,7 @@
>              is added to the mDiscoveredList. The Before, and After Depex are
>              pre-processed as drivers are added to the mDiscoveredList. If an Apriori
>              file exists in the FV those drivers are addeded to the
> -            mScheduledQueue. The mFvHandleList is used to make sure a
> +            mScheduledQueue. The mFwVolList is used to make sure a
>              FV is only processed once.
>  
>    Step #2 - Dispatch. Remove driver from the mScheduledQueue and load and
> @@ -40,13 +40,13 @@
>  //
>  // MM Dispatcher Data structures
>  //
> -#define KNOWN_HANDLE_SIGNATURE  SIGNATURE_32('k','n','o','w')
> +#define KNOWN_FWVOL_SIGNATURE  SIGNATURE_32('k','n','o','w')
>  
>  typedef struct {
> -  UINTN           Signature;
> -  LIST_ENTRY      Link;         // mFvHandleList
> -  EFI_HANDLE      Handle;
> -} KNOWN_HANDLE;
> +  UINTN                      Signature;
> +  LIST_ENTRY                 Link;         // mFwVolList
> +  EFI_FIRMWARE_VOLUME_HEADER *FwVolHeader;
> +} KNOWN_FWVOL;
>  
>  //
>  // Function Prototypes
> @@ -86,9 +86,10 @@ LIST_ENTRY  mDiscoveredList = INITIALIZE_LIST_HEAD_VARIABLE (mDiscoveredList);
>  LIST_ENTRY  mScheduledQueue = INITIALIZE_LIST_HEAD_VARIABLE (mScheduledQueue);
>  
>  //
> -// List of handles who's Fv's have been parsed and added to the mFwDriverList.
> +// List of firmware volume headers whose containing firmware volumes have been
> +// parsed and added to the mFwDriverList.
>  //
> -LIST_ENTRY  mFvHandleList = INITIALIZE_LIST_HEAD_VARIABLE (mFvHandleList);
> +LIST_ENTRY  mFwVolList = INITIALIZE_LIST_HEAD_VARIABLE (mFwVolList);
>  
>  //
>  // Flag for the MM Dispacher.  TRUE if dispatcher is execuing.
> @@ -769,26 +770,30 @@ MmInsertOnScheduledQueueWhileProcessingBeforeAndAfter (
>  }
>  
>  /**
> -  Return TRUE if the Fv has been processed, FALSE if not.
> +  Return TRUE if the firmware volume has been processed, FALSE if not.
>  
> -  @param  FvHandle              The handle of a FV that's being tested
> +  @param  FwVolHeader           The header of the firmware volume that's being
> +                                tested.
>  
> -  @retval TRUE                  Fv protocol on FvHandle has been processed
> -  @retval FALSE                 Fv protocol on FvHandle has not yet been
> -                                processed
> +  @retval TRUE                  The firmware volume denoted by FwVolHeader has
> +                                been processed
> +  @retval FALSE                 The firmware volume denoted by FwVolHeader has
> +                                not yet been processed
>  
>  **/
>  BOOLEAN
>  FvHasBeenProcessed (
> -  IN EFI_HANDLE  FvHandle
> +  IN EFI_FIRMWARE_VOLUME_HEADER *FwVolHeader
>    )
>  {
>    LIST_ENTRY    *Link;
> -  KNOWN_HANDLE  *KnownHandle;
> +  KNOWN_FWVOL   *KnownFwVol;
>  
> -  for (Link = mFvHandleList.ForwardLink; Link != &mFvHandleList; Link = Link->ForwardLink) {
> -    KnownHandle = CR (Link, KNOWN_HANDLE, Link, KNOWN_HANDLE_SIGNATURE);
> -    if (KnownHandle->Handle == FvHandle) {
> +  for (Link = mFwVolList.ForwardLink;
> +       Link != &mFwVolList;
> +       Link = Link->ForwardLink) {
> +    KnownFwVol = CR (Link, KNOWN_FWVOL, Link, KNOWN_FWVOL_SIGNATURE);
> +    if (KnownFwVol->FwVolHeader == FwVolHeader) {
>        return TRUE;
>      }
>    }
> @@ -796,28 +801,29 @@ FvHasBeenProcessed (
>  }
>  
>  /**
> -  Remember that Fv protocol on FvHandle has had it's drivers placed on the
> -  mDiscoveredList. This fucntion adds entries on the mFvHandleList. Items are
> -  never removed/freed from the mFvHandleList.
> +  Remember that the firmware volume denoted by FwVolHeader has had its drivers
> +  placed on mDiscoveredList. This function adds entries to mFwVolList. Items
> +  are never removed/freed from mFwVolList.
>  
> -  @param  FvHandle              The handle of a FV that has been processed
> +  @param  FwVolHeader           The header of the firmware volume that's being
> +                                processed.
>  
>  **/
>  VOID
>  FvIsBeingProcesssed (
> -  IN EFI_HANDLE  FvHandle
> +  IN EFI_FIRMWARE_VOLUME_HEADER *FwVolHeader
>    )
>  {
> -  KNOWN_HANDLE  *KnownHandle;
> +  KNOWN_FWVOL   *KnownFwVol;
>  
> -  DEBUG ((DEBUG_INFO, "FvIsBeingProcesssed - 0x%08x\n", FvHandle));
> +  DEBUG ((DEBUG_INFO, "FvIsBeingProcesssed - 0x%08x\n", KnownFwVol));
>  
> -  KnownHandle = AllocatePool (sizeof (KNOWN_HANDLE));
> -  ASSERT (KnownHandle != NULL);
> +  KnownFwVol = AllocatePool (sizeof (KNOWN_FWVOL));
> +  ASSERT (KnownFwVol != NULL);
>  
> -  KnownHandle->Signature = KNOWN_HANDLE_SIGNATURE;
> -  KnownHandle->Handle = FvHandle;
> -  InsertTailList (&mFvHandleList, &KnownHandle->Link);
> +  KnownFwVol->Signature = KNOWN_FWVOL_SIGNATURE;
> +  KnownFwVol->FwVolHeader = FwVolHeader;
> +  InsertTailList (&mFwVolList, &KnownFwVol->Link);
>  }
>  
>  /**
> @@ -842,12 +848,12 @@ FvIsBeingProcesssed (
>  **/
>  EFI_STATUS
>  MmAddToDriverList (
> -  IN EFI_HANDLE   FvHandle,
> -  IN VOID         *Pe32Data,
> -  IN UINTN        Pe32DataSize,
> -  IN VOID         *Depex,
> -  IN UINTN        DepexSize,
> -  IN EFI_GUID     *DriverName
> +  IN EFI_FIRMWARE_VOLUME_HEADER *FwVolHeader,
> +  IN VOID                       *Pe32Data,
> +  IN UINTN                      Pe32DataSize,
> +  IN VOID                       *Depex,
> +  IN UINTN                      DepexSize,
> +  IN EFI_GUID                   *DriverName
>    )
>  {
>    EFI_MM_DRIVER_ENTRY  *DriverEntry;
> @@ -863,7 +869,7 @@ MmAddToDriverList (
>  
>    DriverEntry->Signature        = EFI_MM_DRIVER_ENTRY_SIGNATURE;
>    CopyGuid (&DriverEntry->FileName, DriverName);
> -  DriverEntry->FvHandle         = FvHandle;
> +  DriverEntry->FwVolHeader      = FwVolHeader;
>    DriverEntry->Pe32Data         = Pe32Data;
>    DriverEntry->Pe32DataSize     = Pe32DataSize;
>    DriverEntry->Depex            = Depex;
> diff --git a/StandaloneMmPkg/Core/FwVol.c b/StandaloneMmPkg/Core/FwVol.c
> index 9fe0c257a43a..99ecf4af4714 100644
> --- a/StandaloneMmPkg/Core/FwVol.c
> +++ b/StandaloneMmPkg/Core/FwVol.c
> @@ -24,22 +24,22 @@ EFI_FV_FILETYPE mMmFileTypes[] = {
>  
>  EFI_STATUS
>  MmAddToDriverList (
> -  IN EFI_HANDLE   FvHandle,
> -  IN VOID         *Pe32Data,
> -  IN UINTN        Pe32DataSize,
> -  IN VOID         *Depex,
> -  IN UINTN        DepexSize,
> -  IN EFI_GUID     *DriverName
> +  IN EFI_FIRMWARE_VOLUME_HEADER *FwVolHeader,
> +  IN VOID                       *Pe32Data,
> +  IN UINTN                      Pe32DataSize,
> +  IN VOID                       *Depex,
> +  IN UINTN                      DepexSize,
> +  IN EFI_GUID                   *DriverName
>    );
>  
>  BOOLEAN
>  FvHasBeenProcessed (
> -  IN EFI_HANDLE  FvHandle
> +  IN EFI_FIRMWARE_VOLUME_HEADER *FwVolHeader
>    );
>  
>  VOID
>  FvIsBeingProcesssed (
> -  IN EFI_HANDLE  FvHandle
> +  IN EFI_FIRMWARE_VOLUME_HEADER *FwVolHeader
>    );
>  
>  EFI_STATUS
>