ArmPkg/CpuDxe: ignore attribute changes during SyncCacheConfig()

To prevent the initial MMU->GCD memory space map synchronization from
stripping permissions attributes [which we cannot use in the GCD memory
space map, unfortunately], implement the same approach as x86, and ignore
SetMemoryAttributes() calls during the time SyncCacheConfig() is in
progress. This is a horrible hack, but is currently the only way we can
implement strict permissions on arbitrary memory regions [as opposed to
PE/COFF text/data sections only]

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
This commit is contained in:
Ard Biesheuvel
2017-02-24 09:58:38 +00:00
parent c325e41585
commit 3b44bb5527
3 changed files with 8 additions and 0 deletions

View File

@@ -188,6 +188,10 @@ CpuSetMemoryAttributes (
UINTN RegionLength;
UINTN RegionArmAttributes;
if (mIsFlushingGCD) {
return EFI_SUCCESS;
}
if ((BaseAddress & (SIZE_4KB - 1)) != 0) {
// Minimum granularity is SIZE_4KB (4KB on ARM)
DEBUG ((EFI_D_PAGE, "CpuSetMemoryAttributes(%lx, %lx, %lx): Minimum ganularity is SIZE_4KB\n", BaseAddress, Length, EfiAttributes));