Re: [Patch] StandaloneMmPkg: Fixed communicating from TF-A failed issue

["Ard Biesheuvel" <ardb@kernel.org>]

On Tue, 8 Jun 2021 at 16:21, Ming Huang <huangming@linux.alibaba.com> wrote:
>
> TF-A: TrustedFirmware-a
> SPM: Secure Partition Manager(MM)
>
> For AArch64, when SPM enable in TF-A, TF-A may communicate to MM
> with buffer address (PLAT_SPM_BUF_BASE). The address is different
> from PcdMmBufferBase which use in edk2.

Then why do we have PcdMmBufferBase?

Is it possible to set PcdMmBufferBase to the correct value?

> Checking address will let TF-A communicate failed to MM. So remove
> below checking code:
> if (NsCommBufferAddr < mNsCommBuffer.PhysicalStart) {
>   return EFI_ACCESS_DENIED;
> }
>
> Signed-off-by: Ming Huang <huangming@linux.alibaba.com>
> ---
>  StandaloneMmPkg/Drivers/StandaloneMmCpu/AArch64/EventHandle.c | 4 ----
>  1 file changed, 4 deletions(-)
>
> diff --git a/StandaloneMmPkg/Drivers/StandaloneMmCpu/AArch64/EventHandle.c b/StandaloneMmPkg/Drivers/StandaloneMmCpu/AArch64/EventHandle.c
> index 63fbe26642..fe98d3181d 100644
> --- a/StandaloneMmPkg/Drivers/StandaloneMmCpu/AArch64/EventHandle.c
> +++ b/StandaloneMmPkg/Drivers/StandaloneMmCpu/AArch64/EventHandle.c
> @@ -103,10 +103,6 @@ PiMmStandaloneArmTfCpuDriverEntry (
>      return EFI_INVALID_PARAMETER;
>    }
>
> -  if (NsCommBufferAddr < mNsCommBuffer.PhysicalStart) {
> -    return EFI_ACCESS_DENIED;
> -  }
> -
>    if ((NsCommBufferAddr + sizeof (EFI_MM_COMMUNICATE_HEADER)) >=
>        (mNsCommBuffer.PhysicalStart + mNsCommBuffer.PhysicalSize)) {
>      return EFI_INVALID_PARAMETER;
> --
> 2.17.1
>