Memory space entry is not removed after calling FreeMemorySpace and RemoveMemorySpace

[Wasim Khan <wasim.khan@nxp.com>]

Hi All,

I am facing a problem that if a add a memory space using 'gDS->AddMemorySpace'  and then remove it using 'gDS->FreeMemorySpace' followed by 'gDS->RemoveMemorySpace'.
I can still see the entry of added memory space in the table shown by 'memmap' command.

I enabled DEBUG_GCD and as per logs , the entry is removed from GcdMemorySpaceMap , but when I run 'memmap' command which gets the memory map using 'gBS->GetMemoryMap', I can see that entry for the added memory space is still present. Steps and Logs are below for reference

Do I need to perform any other steps in order to cleanly remove the memory space entry ?

Regards,
Wasim



Below are the steps and GCD debug logs.
Steps 1 : Add a memory space . We can see that an entry from system memory is added.

Status = gDS->AddMemorySpace (
                                            EfiGcdMemoryTypeSystemMemory,
                                            FixedPcdGet64(PcdSystemMemoryExBase),
                                            SystemMemoryExSize,
                                            EFI_MEMORY_WC | EFI_MEMORY_WT |
                                            EFI_MEMORY_WB
                                            );

               Logs:
                              GCD:AddMemorySpace(Base=0000008080000000,Length=0000000380000000)
                              GcdMemoryType   = SystemMem
                              Capabilities    = 000000000000000E
CoreConvertSpace 774
                              Status = Success
GCDMemType Range                             Capabilities     Attributes
========== ================================= ================ ================
NonExist   0000000000000000-000000009FFFFFFF 0000000000000000 0000000000000000
SystemMem  00000000A0000000-00000000DFFFFFFF 800000000000000E 0000000000000008*
NonExist   00000000E0000000-00000000E01BFFFF 0000000000000000 0000000000000000
SystemMem  00000000E01C0000-00000000FFFFFFFF 800000000000000E 0000000000000008*
NonExist   0000000100000000-000000807FFFFFFF 0000000000000000 0000000000000000
SystemMem  0000008080000000-00000083FFFFFFFF 800000000000000E 0000000000000000
NonExist   0000008400000000-0000FFFFFFFFFFFF 0000000000000000 0000000000000000

GCD:AllocateMemorySpace(Base=0000008080000000,Length=0000000380000000)
  GcdAllocateType = AtAddress
  GcdMemoryType   = SystemMem
  Alignment       = 0000000000001000
  ImageHandle     = FED1FF98
  DeviceHandle    = 0
  Status = Success  (BaseAddress = 0000008080000000)
GCDMemType Range                             Capabilities     Attributes
========== ================================= ================ ================
NonExist   0000000000000000-000000009FFFFFFF 0000000000000000 0000000000000000
SystemMem  00000000A0000000-00000000DFFFFFFF 800000000000000E 0000000000000008*
NonExist   00000000E0000000-00000000E01BFFFF 0000000000000000 0000000000000000
SystemMem  00000000E01C0000-00000000FFFFFFFF 800000000000000E 0000000000000008*
NonExist   0000000100000000-000000807FFFFFFF 0000000000000000 0000000000000000
SystemMem  0000008080000000-00000083FFFFFFFF 800000000000000E 0000000000000000*
NonExist   0000008400000000-0000FFFFFFFFFFFF 0000000000000000 0000000000000000


Step2: Free the memory space
               Status = gDS->FreeMemorySpace (
               FixedPcdGet64(PcdSystemMemoryExBase),
               SystemMemoryExSize
               );

               Logs:
                              GCD:FreeMemorySpace(Base=0000008080000000,Length=0000000380000000)
Status = Success
GCDMemType Range                             Capabilities     Attributes
========== ================================= ================ ================
NonExist   0000000000000000-000000009FFFFFFF 0000000000000000 0000000000000000
SystemMem  00000000A0000000-00000000DFFFFFFF 800000000000000E 0000000000000008*
NonExist   00000000E0000000-00000000E01BFFFF 0000000000000000 0000000000000000
SystemMem  00000000E01C0000-00000000FFFFFFFF 800000000000000E 0000000000000008*
NonExist   0000000100000000-000000807FFFFFFF 0000000000000000 0000000000000000
SystemMem  0000008080000000-00000083FFFFFFFF 800000000000000E 0000000000000000
NonExist   0000008400000000-0000FFFFFFFFFFFF 0000000000000000 0000000000000000


Step3: Remove the memory space , As we can see that entry 'SystemMem  0000008080000000-00000083FFFFFFFF' is removed.
               Status = gDS->RemoveMemorySpace (
               FixedPcdGet64(PcdSystemMemoryExBase),
               SystemMemoryExSize
               );

               Logs:
                              GCD:RemoveMemorySpace(Base=0000008080000000,Length=0000000380000000)
Status = Success
GCDMemType Range                             Capabilities     Attributes
========== ================================= ================ ================
NonExist   0000000000000000-000000009FFFFFFF 0000000000000000 0000000000000000
SystemMem  00000000A0000000-00000000DFFFFFFF 800000000000000E 0000000000000008*
NonExist   00000000E0000000-00000000E01BFFFF 0000000000000000 0000000000000000
SystemMem  00000000E01C0000-00000000FFFFFFFF 800000000000000E 0000000000000008*
NonExist   0000000100000000-0000FFFFFFFFFFFF 0000000000000000 0000000000000000

Step4 : Run the 'memmap' command. As we can see that entry is still present.
               Shell> memmap
Type       Start            End              # Pages          Attributes
Available  00000000A0000000-00000000DFFFFFFF 0000000000040000 000000000000000E
Available  00000000E01C0000-00000000E53C0FFF 0000000000005201 000000000000000E
BS_Data    00000000E53C1000-00000000E5D99FFF 00000000000009D9 000000000000000E
...
Available  0000008080000000-00000083FFFFFFFF 0000000000380000 000000000000000E
                              ...