Re: [PATCH V2 3/3] UefiCpuPkg: Add New Memory Attributes

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

Hi Oleksiy,

On 06/30/20 23:11, Oleksiy Yakovlev wrote:
> Hi Laszlo.
> 
> I think WP should be included also. Spec says that WP "typically used as a cacheability attribute today".
> 
> Do you want me to submit just additional patch for CpuDxe.h, or resubmit the whole series adding this inclusion of WP to EFI_MEMORY_CACHETYPE_MASK in  CpuDxe.h?

I'd suggest posting a v3 patch set, with 4 patches in total:

- v4 1/4: equals v3 1/3
- v4 2/4: equals v3 2/3
- v4 3/4: new patch (add WP to EFI_MEMORY_CACHETYPE_MASK)
- v4 4/4: v3 3/3, updated

The reason for my suggestion is that, once you add EFI_MEMORY_WP to
EFI_MEMORY_CACHETYPE_MASK, the present patch will no longer apply
verbatim (it will have to be rebased). Namely, the hunk that removes the
EFI_MEMORY_CACHETYPE_MASK #define needs to be updated for EFI_MEMORY_WP.

When posting v4, please pick up the feedback tags you received during
the v3 review. (The small update for the final patch in the series does
not invalidate my R-b.)

Thank you!
Laszlo


> -----Original Message-----
> From: Laszlo Ersek [mailto:lersek@redhat.com] 
> Sent: Wednesday, June 24, 2020 5:42 AM
> To: Oleksiy Yakovlev; devel@edk2.groups.io
> Cc: liming.gao@intel.com; michael.d.kinney@intel.com; dandan.bi@intel.com; ray.ni@intel.com; rahul1.kumar@intel.com; Felix Polyudov; Eric Dong
> Subject: Re: [PATCH V2 3/3] UefiCpuPkg: Add New Memory Attributes
> 
> On 06/23/20 23:55, Oleksiy Yakovlev wrote:
>> Add usage of EFI_MEMORY_SP and EFI_MEMORY_CPU_CRYPTO
>> attributes introduced in UEFI 2.8.
>> (UEFI 2.8, mantis 1919 and 1872).
>> Use attributes bitmasks, defined in MdePkg.
>>
>> Signed-off-by: Oleksiy Yakovlev <oleksiyy@ami.com>
>> ---
>>  UefiCpuPkg/CpuDxe/CpuDxe.c                         | 11 ++++-------
>>  UefiCpuPkg/CpuDxe/CpuDxe.h                         | 12 ------------
>>  UefiCpuPkg/CpuDxe/CpuPageTable.c                   |  6 +++---
>>  UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c |  2 +-
>>  4 files changed, 8 insertions(+), 23 deletions(-)
>>
>> diff --git a/UefiCpuPkg/CpuDxe/CpuDxe.c b/UefiCpuPkg/CpuDxe/CpuDxe.c
>> index a571fc3..52cc26e 100644
>> --- a/UefiCpuPkg/CpuDxe/CpuDxe.c
>> +++ b/UefiCpuPkg/CpuDxe/CpuDxe.c
>> @@ -10,9 +10,6 @@
>>  #include "CpuMp.h"
>>  #include "CpuPageTable.h"
>>  
>> -#define CACHE_ATTRIBUTE_MASK   (EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_WP)
>> -#define MEMORY_ATTRIBUTE_MASK  (EFI_MEMORY_RP | EFI_MEMORY_XP | EFI_MEMORY_RO)
>> -
>>  //
>>  // Global Variables
>>  //
>> @@ -417,8 +414,8 @@ CpuSetMemoryAttributes (
>>      return EFI_SUCCESS;
>>    }
>>  
>> -  CacheAttributes = Attributes & CACHE_ATTRIBUTE_MASK;
>> -  MemoryAttributes = Attributes & MEMORY_ATTRIBUTE_MASK;
>> +  CacheAttributes = Attributes & EFI_CACHE_ATTRIBUTE_MASK;
>> +  MemoryAttributes = Attributes & EFI_MEMORY_ATTRIBUTE_MASK;
>>  
>>    if (Attributes != (CacheAttributes | MemoryAttributes)) {
>>      return EFI_INVALID_PARAMETER;
> 
> OK.
> 
>> @@ -677,7 +674,7 @@ SetGcdMemorySpaceAttributes (
>>      gDS->SetMemorySpaceAttributes (
>>             RegionStart,
>>             RegionLength,
>> -           (MemorySpaceMap[Index].Attributes & ~EFI_MEMORY_CACHETYPE_MASK) | (MemorySpaceMap[Index].Capabilities & Attributes)
>> +           (MemorySpaceMap[Index].Attributes & ~EFI_CACHE_ATTRIBUTE_MASK) | (MemorySpaceMap[Index].Capabilities & Attributes)
>>             );
>>    }
>>  
>> @@ -754,7 +751,7 @@ RefreshMemoryAttributesFromMtrr (
>>      gDS->SetMemorySpaceAttributes (
>>             MemorySpaceMap[Index].BaseAddress,
>>             MemorySpaceMap[Index].Length,
>> -           (MemorySpaceMap[Index].Attributes & ~EFI_MEMORY_CACHETYPE_MASK) |
>> +           (MemorySpaceMap[Index].Attributes & ~EFI_CACHE_ATTRIBUTE_MASK) |
>>             (MemorySpaceMap[Index].Capabilities & DefaultAttributes)
>>             );
>>    }
>> diff --git a/UefiCpuPkg/CpuDxe/CpuDxe.h b/UefiCpuPkg/CpuDxe/CpuDxe.h
>> index 9299eaa..9771ec8 100644
>> --- a/UefiCpuPkg/CpuDxe/CpuDxe.h
>> +++ b/UefiCpuPkg/CpuDxe/CpuDxe.h
>> @@ -39,18 +39,6 @@
>>  #include <Guid/IdleLoopEvent.h>
>>  #include <Guid/VectorHandoffTable.h>
>>  
>> -#define EFI_MEMORY_CACHETYPE_MASK     (EFI_MEMORY_UC  | \
>> -                                       EFI_MEMORY_WC  | \
>> -                                       EFI_MEMORY_WT  | \
>> -                                       EFI_MEMORY_WB  | \
>> -                                       EFI_MEMORY_UCE   \
>> -                                       )
>> -
>> -#define EFI_MEMORY_PAGETYPE_MASK      (EFI_MEMORY_RP  | \
>> -                                       EFI_MEMORY_XP  | \
>> -                                       EFI_MEMORY_RO    \
>> -                                       )
>> -
>>  #define HEAP_GUARD_NONSTOP_MODE       \
>>          ((PcdGet8 (PcdHeapGuardPropertyMask) & (BIT6|BIT4|BIT1|BIT0)) > BIT6)
>>  
> 
> (1) These changes have an additional effect. EFI_MEMORY_CACHETYPE_MASK
> does not include EFI_MEMORY_WP, but EFI_CACHE_ATTRIBUTE_MASK does.
> 
> (1a) If that change is intentional, then this patch can remain as it is,
> but we need an extra patch prepended (i.e., inserted between v2 patches
> #2 and #3), for adding EFI_MEMORY_WP to EFI_MEMORY_CACHETYPE_MASK first.
> 
> (1b) If the EFI_MEMORY_WP change is not intended (i.e., it is an
> oversight in this patch), then in every spot where we replace
> EFI_MEMORY_CACHETYPE_MASK with EFI_CACHE_ATTRIBUTE_MASK, we need to
> account for EFI_MEMORY_WP separately.
> 
> ... After reading up on EFI_MEMORY_WP in the UEFI spec, I think it's
> (1a) -- meaning that, this patch is correct, in itself. But, we should
> still not hide the EFI_MEMORY_WP bugfix, for EFI_MEMORY_CACHETYPE_MASK,
> in this patch.
> 
> So please insert a new patch just before this one, that does nothing
> other than include EFI_MEMORY_WP in EFI_MEMORY_CACHETYPE_MASK.
> 
> The rest of the patch looks OK to me. Therefore, for this patch (in itself):
> 
> Reviewed-by: Laszlo Ersek <lersek@redhat.com>
> 
> Eric, Ray, Rahul: correct me if I'm wrong, please.
> 
> Thanks,
> Laszlo
> 
>> diff --git a/UefiCpuPkg/CpuDxe/CpuPageTable.c b/UefiCpuPkg/CpuDxe/CpuPageTable.c
>> index 0a02cb3..06ee1b8 100644
>> --- a/UefiCpuPkg/CpuDxe/CpuPageTable.c
>> +++ b/UefiCpuPkg/CpuDxe/CpuPageTable.c
>> @@ -717,7 +717,7 @@ ConvertMemoryPageAttributes (
>>      return RETURN_INVALID_PARAMETER;
>>    }
>>  
>> -  if ((Attributes & ~(EFI_MEMORY_RP | EFI_MEMORY_RO | EFI_MEMORY_XP)) != 0) {
>> +  if ((Attributes & ~EFI_MEMORY_ATTRIBUTE_MASK) != 0) {
>>      DEBUG ((DEBUG_ERROR, "Attributes(0x%lx) has unsupported bit\n", Attributes));
>>      return EFI_UNSUPPORTED;
>>    }
>> @@ -1018,9 +1018,9 @@ RefreshGcdMemoryAttributesFromPaging (
>>  
>>        Length = MIN (PageLength, MemorySpaceLength);
>>        if (Attributes != (MemorySpaceMap[Index].Attributes &
>> -                         EFI_MEMORY_PAGETYPE_MASK)) {
>> +                         EFI_MEMORY_ATTRIBUTE_MASK)) {
>>          NewAttributes = (MemorySpaceMap[Index].Attributes &
>> -                         ~EFI_MEMORY_PAGETYPE_MASK) | Attributes;
>> +                         ~EFI_MEMORY_ATTRIBUTE_MASK) | Attributes;
>>          Status = gDS->SetMemorySpaceAttributes (
>>                          BaseAddress,
>>                          Length,
>> diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c
>> index 9c5a92a..ebfc46a 100644
>> --- a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c
>> +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c
>> @@ -435,7 +435,7 @@ ConvertMemoryPageAttributes (
>>    EFI_PHYSICAL_ADDRESS              MaximumSupportMemAddress;
>>  
>>    ASSERT (Attributes != 0);
>> -  ASSERT ((Attributes & ~(EFI_MEMORY_RP | EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0);
>> +  ASSERT ((Attributes & ~EFI_MEMORY_ATTRIBUTE_MASK) == 0);
>>  
>>    ASSERT ((BaseAddress & (SIZE_4KB - 1)) == 0);
>>    ASSERT ((Length & (SIZE_4KB - 1)) == 0);
>>
> 
> 
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