diff mbox

[edk2,2/3] MdeModulePkg: S3SaveStateDxe, SmmS3SaveState: save 64-bit LoopTimes

Message ID 20161201175556.2479-3-lersek@redhat.com
State Accepted
Commit 387ccad8f6f3acbae80bbeb816c944dec672aa66
Headers show

Commit Message

Laszlo Ersek Dec. 1, 2016, 5:55 p.m. UTC 
The BootScriptWriteMemPoll() helper function in both drivers does the
following:

- pop Delay from the variable argument list as UINT64, then truncate it to
  UINTN,

- divide Delay by 10, using DivU64x32Remainder(), then store the quotient
  in LoopTimes (also UINTN),

- pass LoopTimes to S3BootScriptSaveMemPoll() as last argument.

The truncation to UINTN is superfluous and wrong in this logic (not to
mention incompatible with the PI spec); it prevents callers from
specifying Delays longer than 0xFFFF_FFFF * 100ns (approximately 429
seconds == 7 minutes 9 seconds) on Ia32. In particular it prevents callers
from specifying an infinite timeout (for example, 0xFFFF_FFFF_FFFF_FFFF *
100ns, approximately 58494 years).

Change the type of Delay and LoopTimes to UINT64. Keep the same logic,
just remove the truncations. The resultant LoopTimes values can be safely
passed to S3BootScriptSaveMemPoll() thanks to the previous patch.

Cc: Feng Tian <feng.tian@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>

---
 MdeModulePkg/Universal/Acpi/S3SaveStateDxe/S3SaveState.c    | 8 ++++----
 MdeModulePkg/Universal/Acpi/SmmS3SaveState/SmmS3SaveState.c | 8 ++++----
 2 files changed, 8 insertions(+), 8 deletions(-)

-- 
2.9.2


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diff mbox

Patch

diff --git a/MdeModulePkg/Universal/Acpi/S3SaveStateDxe/S3SaveState.c b/MdeModulePkg/Universal/Acpi/S3SaveStateDxe/S3SaveState.c
index 32263c96c56b..efc0ef914064 100644
--- a/MdeModulePkg/Universal/Acpi/S3SaveStateDxe/S3SaveState.c
+++ b/MdeModulePkg/Universal/Acpi/S3SaveStateDxe/S3SaveState.c
@@ -343,15 +343,15 @@  BootScriptWriteMemPoll (
   UINT64                     Address;                                    
   VOID                      *Data;                                    
   VOID                      *DataMask;                                  
-  UINTN                     Delay;                                   
-  UINTN                     LoopTimes;
+  UINT64                    Delay;
+  UINT64                    LoopTimes;
   UINT32                    Remainder;
 
   Width    = VA_ARG (Marker, S3_BOOT_SCRIPT_LIB_WIDTH);                  
   Address  = VA_ARG (Marker, UINT64);                                    
   Data     = VA_ARG (Marker, VOID *);                                    
   DataMask = VA_ARG (Marker, VOID *);                                    
-  Delay    = (UINTN)VA_ARG (Marker, UINT64);                            
+  Delay    = VA_ARG (Marker, UINT64);
   //
   // According to the spec, the interval between 2 polls is 100ns,
   // but the unit of Duration for S3BootScriptSaveMemPoll() is microsecond(1000ns).
@@ -359,7 +359,7 @@  BootScriptWriteMemPoll (
   // Duration will be minimum 1(microsecond) to be minimum deviation,
   // so LoopTimes = Delay / 10.
   //
-  LoopTimes = (UINTN) DivU64x32Remainder (
+  LoopTimes = DivU64x32Remainder (
                 Delay,
                 10,
                 &Remainder
diff --git a/MdeModulePkg/Universal/Acpi/SmmS3SaveState/SmmS3SaveState.c b/MdeModulePkg/Universal/Acpi/SmmS3SaveState/SmmS3SaveState.c
index 739f19eac437..0d1580dc35ab 100644
--- a/MdeModulePkg/Universal/Acpi/SmmS3SaveState/SmmS3SaveState.c
+++ b/MdeModulePkg/Universal/Acpi/SmmS3SaveState/SmmS3SaveState.c
@@ -342,15 +342,15 @@  BootScriptWriteMemPoll (
   UINT64                     Address;                                    
   VOID                      *Data;                                       
   VOID                      *DataMask;                                   
-  UINTN                      Delay;                                       
-  UINTN                      LoopTimes;
+  UINT64                     Delay;
+  UINT64                     LoopTimes;
   UINT32                     Remainder;
 
   Width    = VA_ARG (Marker, S3_BOOT_SCRIPT_LIB_WIDTH);                  
   Address  = VA_ARG (Marker, UINT64);                                    
   Data     = VA_ARG (Marker, VOID *);                                    
   DataMask = VA_ARG (Marker, VOID *);                                    
-  Delay    = (UINTN)VA_ARG (Marker, UINT64);                            
+  Delay    = VA_ARG (Marker, UINT64);
   //
   // According to the spec, the interval between 2 polls is 100ns,
   // but the unit of Duration for S3BootScriptSaveMemPoll() is microsecond(1000ns).
@@ -358,7 +358,7 @@  BootScriptWriteMemPoll (
   // Duration will be minimum 1(microsecond) to be minimum deviation,
   // so LoopTimes = Delay / 10.
   //
-  LoopTimes = (UINTN) DivU64x32Remainder (
+  LoopTimes = DivU64x32Remainder (
                 Delay,
                 10,
                 &Remainder