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authorLaszlo Ersek <lersek@redhat.com>2017-11-08 19:43:21 +0100
committerLaszlo Ersek <lersek@redhat.com>2017-11-17 18:12:12 +0100
commit9d9350a579d3f3d52ea1012111fad300c4e19fa2 (patch)
tree542d624af081ee04d243a37fe33a4f62692dac21 /OvmfPkg/Sec
parent9f75aacc7ab5410345b4811901a78a375851aa8b (diff)
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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>
Diffstat (limited to 'OvmfPkg/Sec')
-rw-r--r--OvmfPkg/Sec/Ia32/SecEntry.nasm18
-rw-r--r--OvmfPkg/Sec/SecMain.inf1
2 files changed, 19 insertions, 0 deletions
diff --git a/OvmfPkg/Sec/Ia32/SecEntry.nasm b/OvmfPkg/Sec/Ia32/SecEntry.nasm
index 7fee1c2b2e..03501969eb 100644
--- a/OvmfPkg/Sec/Ia32/SecEntry.nasm
+++ b/OvmfPkg/Sec/Ia32/SecEntry.nasm
@@ -29,6 +29,11 @@ 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
;
@@ -36,6 +41,19 @@ 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
;
%define SEC_TOP_OF_STACK (FixedPcdGet32 (PcdOvmfSecPeiTempRamBase) + \
diff --git a/OvmfPkg/Sec/SecMain.inf b/OvmfPkg/Sec/SecMain.inf
index 711b595309..6051cb3c6c 100644
--- a/OvmfPkg/Sec/SecMain.inf
+++ b/OvmfPkg/Sec/SecMain.inf
@@ -71,6 +71,7 @@
gEfiMdePkgTokenSpaceGuid.PcdGuidedExtractHandlerTableAddress
gUefiOvmfPkgTokenSpaceGuid.PcdGuidedExtractHandlerTableSize
gUefiOvmfPkgTokenSpaceGuid.PcdOvmfDecompressionScratchEnd
+ gEfiMdeModulePkgTokenSpaceGuid.PcdInitValueInTempStack
[FeaturePcd]
gUefiOvmfPkgTokenSpaceGuid.PcdSmmSmramRequire