OvmfPkg/Sec/Ia32: seed the temporary RAM with PcdInitValueInTempStack

This allows the PEI core to report the maximum temporary SEC/PEI stack
usage on the DEBUG_INFO level, in the PeiCheckAndSwitchStack() function
[MdeModulePkg/Core/Pei/Dispatcher/Dispatcher.c]:

* Normal boot:

> Temp Stack : BaseAddress=0x814000 Length=0x4000
> Temp Heap  : BaseAddress=0x810000 Length=0x4000
> Total temporary memory:    32768 bytes.
>   temporary memory stack ever used:       3664 bytes. <----
>   temporary memory heap used for HobList: 5904 bytes.
>   temporary memory heap occupied by memory pages: 0 bytes.

* S3 resume (with PEI decompression / SMM):

> Temp Stack : BaseAddress=0x814000 Length=0x4000
> Temp Heap  : BaseAddress=0x810000 Length=0x4000
> Total temporary memory:    32768 bytes.
>   temporary memory stack ever used:       3428 bytes. <----
>   temporary memory heap used for HobList: 4816 bytes.
>   temporary memory heap occupied by memory pages: 0 bytes.

I unit-tested this change by transitorily adding an infinite loop right
after the "rep stosd", and dumping the guest's temp SEC/PEI RAM (32KB
currently) while the guest was stuck in the loop. The dump includes one
dword from before and after the temp SEC/PEI RAM:

> $ virsh qemu-monitor-command GUEST_NAME --hmp 'xp /8194wx 0x80FFFC'
>
> 000000000080fffc: 0x00000000 0x5aa55aa5 0x5aa55aa5 0x5aa55aa5
> 000000000081000c: 0x5aa55aa5 0x5aa55aa5 0x5aa55aa5 0x5aa55aa5
> ...
> 0000000000817fec: 0x5aa55aa5 0x5aa55aa5 0x5aa55aa5 0x5aa55aa5
> 0000000000817ffc: 0x5aa55aa5 0x00000000

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=747
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
This commit is contained in:
Laszlo Ersek 2017-11-08 19:43:21 +01:00
parent 9f75aacc7a
commit 9d9350a579
2 changed files with 19 additions and 0 deletions

View File

@ -29,12 +29,30 @@ extern ASM_PFX(SecCoreStartupWithStack)
; @param[in] EAX Initial value of the EAX register (BIST: Built-in Self Test)
; @param[in] DI 'BP': boot-strap processor, or 'AP': application processor
; @param[in] EBP Pointer to the start of the Boot Firmware Volume
; @param[in] DS Selector allowing flat access to all addresses
; @param[in] ES Selector allowing flat access to all addresses
; @param[in] FS Selector allowing flat access to all addresses
; @param[in] GS Selector allowing flat access to all addresses
; @param[in] SS Selector allowing flat access to all addresses
;
; @return None This routine does not return
;
global ASM_PFX(_ModuleEntryPoint)
ASM_PFX(_ModuleEntryPoint):
;
; Fill the temporary RAM with the initial stack value.
; The loop below will seed the heap as well, but that's harmless.
;
mov eax, FixedPcdGet32 (PcdInitValueInTempStack) ; dword to store
mov edi, FixedPcdGet32 (PcdOvmfSecPeiTempRamBase) ; base address,
; relative to
; ES
mov ecx, FixedPcdGet32 (PcdOvmfSecPeiTempRamSize) / 4 ; dword count
cld ; store from base
; up
rep stosd
;
; Load temporary RAM stack based on PCDs
;

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@ -71,6 +71,7 @@
gEfiMdePkgTokenSpaceGuid.PcdGuidedExtractHandlerTableAddress
gUefiOvmfPkgTokenSpaceGuid.PcdGuidedExtractHandlerTableSize
gUefiOvmfPkgTokenSpaceGuid.PcdOvmfDecompressionScratchEnd
gEfiMdeModulePkgTokenSpaceGuid.PcdInitValueInTempStack
[FeaturePcd]
gUefiOvmfPkgTokenSpaceGuid.PcdSmmSmramRequire