The GCC 5.4 will optimize mNumberToFinish in EarlyInitializeCpu(). It will cause S3 resume failure.
Adding *volatile* could make sure compiler does not so such optimization. Cc: Paolo Bonzini <pbonz...@redhat.com> Cc: Laszlo Ersek <ler...@redhat.com> Cc: Jiewen Yao <jiewen....@intel.com> Cc: Feng Tian <feng.t...@intel.com> Cc: Michael D Kinney <michael.d.kin...@intel.com> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Jeff Fan <jeff....@intel.com> --- UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c b/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c index 3fb6864..f13ff3e 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c @@ -55,7 +55,7 @@ AsmGetAddressMap ( #define LEGACY_REGION_BASE (0xA0000 - LEGACY_REGION_SIZE) ACPI_CPU_DATA mAcpiCpuData; -UINT32 mNumberToFinish; +volatile UINT32 mNumberToFinish; MP_CPU_EXCHANGE_INFO *mExchangeInfo; BOOLEAN mRestoreSmmConfigurationInS3 = FALSE; VOID *mGdtForAp = NULL; @@ -371,7 +371,7 @@ EarlyMPRendezvousProcedure ( // // Count down the number with lock mechanism. // - InterlockedDecrement (&mNumberToFinish); + InterlockedDecrement ((UINT32 *) &mNumberToFinish); } /** @@ -406,7 +406,7 @@ MPRendezvousProcedure ( TopOfStack = (UINT32) (UINTN) Stack + sizeof (Stack); TopOfStack &= ~(UINT32) (CPU_STACK_ALIGNMENT - 1); CopyMem ((VOID *) (UINTN) mApHltLoopCode, mApHltLoopCodeTemplate, sizeof (mApHltLoopCodeTemplate)); - TransferApToSafeState ((UINT32) (UINTN) mApHltLoopCode, TopOfStack, &mNumberToFinish); + TransferApToSafeState ((UINT32) (UINTN) mApHltLoopCode, TopOfStack, (UINT32 *) &mNumberToFinish); } /** -- 2.9.3.windows.2 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
