From f2509d6d3efbed3cf90c44ace94a331b912b0017 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Thu, 8 Sep 2016 08:40:09 +0100 Subject: [PATCH] ArmVirtPkg: restrict mapping attributes of normal memory to EFI_MEMORY_WB In general, on an ARM system, mapping normal memory as device memory may have unintended side effects, given that unaligned accesses or loads and stores with special semantics (e.g., load/store exclusive) may fault or may not work as expected. Under KVM, the situation is even worse, since the host may not expect the guest to perform uncached accesses, and so writes to such an uncached region may get lost completely. Since the only safe mapping type under KVM is EFI_MEMORY_WB, remove all other memory type attributes. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel Reviewed-by: Laszlo Ersek --- ArmVirtPkg/HighMemDxe/HighMemDxe.c | 3 +-- .../Library/ArmVirtMemoryInitPeiLib/ArmVirtMemoryInitPeiLib.c | 3 --- 2 files changed, 1 insertion(+), 5 deletions(-) diff --git a/ArmVirtPkg/HighMemDxe/HighMemDxe.c b/ArmVirtPkg/HighMemDxe/HighMemDxe.c index 7fd7e8e9a5..4d56e6236b 100644 --- a/ArmVirtPkg/HighMemDxe/HighMemDxe.c +++ b/ArmVirtPkg/HighMemDxe/HighMemDxe.c @@ -78,8 +78,7 @@ InitializeHighMemDxe ( Status = gDS->AddMemorySpace ( EfiGcdMemoryTypeSystemMemory, CurBase, CurSize, - EFI_MEMORY_WB | EFI_MEMORY_WC | - EFI_MEMORY_WT | EFI_MEMORY_UC); + EFI_MEMORY_WB); if (EFI_ERROR (Status)) { DEBUG ((EFI_D_ERROR, diff --git a/ArmVirtPkg/Library/ArmVirtMemoryInitPeiLib/ArmVirtMemoryInitPeiLib.c b/ArmVirtPkg/Library/ArmVirtMemoryInitPeiLib/ArmVirtMemoryInitPeiLib.c index 251e5314e6..6f3e54b7af 100644 --- a/ArmVirtPkg/Library/ArmVirtMemoryInitPeiLib/ArmVirtMemoryInitPeiLib.c +++ b/ArmVirtPkg/Library/ArmVirtMemoryInitPeiLib/ArmVirtMemoryInitPeiLib.c @@ -68,9 +68,6 @@ MemoryPeim ( ResourceAttributes = ( EFI_RESOURCE_ATTRIBUTE_PRESENT | EFI_RESOURCE_ATTRIBUTE_INITIALIZED | - EFI_RESOURCE_ATTRIBUTE_UNCACHEABLE | - EFI_RESOURCE_ATTRIBUTE_WRITE_COMBINEABLE | - EFI_RESOURCE_ATTRIBUTE_WRITE_THROUGH_CACHEABLE | EFI_RESOURCE_ATTRIBUTE_WRITE_BACK_CACHEABLE | EFI_RESOURCE_ATTRIBUTE_TESTED ); -- 2.39.2