From 647cd40cf6658f52e0c6d4c356620a4dedd425ba Mon Sep 17 00:00:00 2001 From: Oliver Smith-Denny Date: Tue, 23 May 2023 13:36:23 -0700 Subject: ArmPkg/CpuDxe AARCH64: Report Memory Protection Attributes To GCD REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4463 When the AARCH64 CpuDxe attempts to SyncCacheConfig() with the GCD, it collects the page attributes as: EntryAttribute = Entry & TT_ATTR_INDX_MASK However, TT_ATTR_INDX_MASK only masks the cacheability attributes and drops the memory protections attributes. Importantly, it also drops the TT_AF (access flag) which is now wired up in EDK2 to represent EFI_MEMORY_RP, so by default all SystemMem pages will report as EFI_MEMORY_RP to the GCD. The GCD currently drops that silently, because the Capabilities field in the GCD does not support EFI_MEMORY_RP by default. However, some ranges may support EFI_MEMORY_RP and incorrectly mark those ranges as read protected. In conjunction with another change on the mailing list (see: https://edk2.groups.io/g/devel/topic/98505340), this causes an access flag fault incorrectly. See the linked BZ below for full details. This patch exposes all memory protections attributes to the GCD layer so it can correctly set pages as EFI_MEMORY[RP|XP|RO] when it initially syncs. Cc: Leif Lindholm Cc: Sami Mujawar Cc: Taylor Beebe Cc: Sean Brogan Signed-off-by: Oliver Smith-Denny Reviewed-by: Ard Biesheuvel Reviewed-by: Michael Kubacki --- ArmPkg/Drivers/CpuDxe/AArch64/Mmu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'ArmPkg/Drivers') diff --git a/ArmPkg/Drivers/CpuDxe/AArch64/Mmu.c b/ArmPkg/Drivers/CpuDxe/AArch64/Mmu.c index 0859c74..1d02e41 100644 --- a/ArmPkg/Drivers/CpuDxe/AArch64/Mmu.c +++ b/ArmPkg/Drivers/CpuDxe/AArch64/Mmu.c @@ -120,7 +120,7 @@ GetFirstPageAttribute ( } else if (((FirstEntry & TT_TYPE_MASK) == TT_TYPE_BLOCK_ENTRY) || ((TableLevel == 3) && ((FirstEntry & TT_TYPE_MASK) == TT_TYPE_BLOCK_ENTRY_LEVEL3))) { - return FirstEntry & TT_ATTR_INDX_MASK; + return FirstEntry & TT_ATTRIBUTES_MASK; } else { return INVALID_ENTRY; } @@ -158,7 +158,7 @@ GetNextEntryAttribute ( for (Index = 0; Index < EntryCount; Index++) { Entry = TableAddress[Index]; EntryType = Entry & TT_TYPE_MASK; - EntryAttribute = Entry & TT_ATTR_INDX_MASK; + EntryAttribute = Entry & TT_ATTRIBUTES_MASK; // If Entry is a Table Descriptor type entry then go through the sub-level table if ((EntryType == TT_TYPE_BLOCK_ENTRY) || -- cgit v1.1