The ARM ArmMmuLib code currently does not take into account that setting permissions on a region should take into account that a region may not be mapped yet to begin with.
So when updating a section descriptor whose old value is zero, pass in the address explicitly. Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Ard Biesheuvel <[email protected]> --- ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c b/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c index ec51e072ab43..889b22867dc7 100644 --- a/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c +++ b/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c @@ -695,8 +695,12 @@ UpdateSectionEntries ( } else { // still a section entry - // mask off appropriate fields - Descriptor = CurrentDescriptor & ~EntryMask; + if (CurrentDescriptor != 0) { + // mask off appropriate fields + Descriptor = CurrentDescriptor & ~EntryMask; + } else { + Descriptor = ((UINTN)FirstLevelIdx + i) << TT_DESCRIPTOR_SECTION_BASE_SHIFT; + } // mask in new attributes and/or permissions Descriptor |= EntryValue; -- 2.19.1 _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
