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UefiCpuPkg/CpuDxe: implement non-stop mode for uefi

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Same as SMM profile feature, a special #PF is used to set page attribute
to 'present' and a special #DB handler to reset it back to 'not-present',
right after the instruction causing #PF got executed.

Since the new #PF handler won't enter into dead-loop, the instruction
which caused the #PF will get chance to re-execute with accessible pages.

The exception message will still be printed out on debug console so that
the developer/QA can find that there's potential heap overflow or null
pointer access occurred.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
This commit is contained in:
Jian J Wang
2018-08-20 11:31:00 +08:00
parent 16b918bbaf
commit dcc026217f
4 changed files with 237 additions and 6 deletions
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34
UefiCpuPkg/CpuDxe/CpuMp.c
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@@ -673,10 +673,6 @@ InitializeMpExceptionStackSwitchHandlers (
UINT8 *GdtBuffer;
UINT8 *StackTop;
if (!PcdGetBool (PcdCpuStackGuard)) {
return;
}
ExceptionNumber = FixedPcdGetSize (PcdCpuStackSwitchExceptionList);
NewStackSize = FixedPcdGet32 (PcdCpuKnownGoodStackSize) * ExceptionNumber;
@@ -790,6 +786,32 @@ InitializeMpExceptionStackSwitchHandlers (
}
}
/**
Initializes MP exceptions handlers for special features, such as Heap Guard
and Stack Guard.
**/
VOID
InitializeMpExceptionHandlers (
VOID
)
{
//
// Enable non-stop mode for #PF triggered by Heap Guard or NULL Pointer
// Detection.
//
if (HEAP_GUARD_NONSTOP_MODE || NULL_DETECTION_NONSTOP_MODE) {
RegisterCpuInterruptHandler (EXCEPT_IA32_DEBUG, DebugExceptionHandler);
RegisterCpuInterruptHandler (EXCEPT_IA32_PAGE_FAULT, PageFaultExceptionHandler);
}
//
// Setup stack switch for Stack Guard feature.
//
if (PcdGetBool (PcdCpuStackGuard)) {
InitializeMpExceptionStackSwitchHandlers ();
}
}
/**
Initialize Multi-processor support.
@@ -814,9 +836,9 @@ InitializeMpSupport (
DEBUG ((DEBUG_INFO, "Detect CPU count: %d\n", mNumberOfProcessors));
//
// Initialize exception stack switch handlers for each logic processor.
// Initialize special exception handlers for each logic processor.
//
InitializeMpExceptionStackSwitchHandlers ();
InitializeMpExceptionHandlers ();
//
// Update CPU healthy information from Guided HOB