| Message ID | 1486661891-7888-4-git-send-email-ard.biesheuvel@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | ArmPkg: add groundwork for DXE image protection | expand |
On Thu, Feb 09, 2017 at 05:38:10PM +0000, Ard Biesheuvel wrote: > Currently, we have not implemented support on 32-bit ARM for managing > permission bits in the page tables. Since the new DXE page protection > for PE/COFF images may invoke EFI_CPU_ARCH_PROTOCOL.SetMemoryAttributes() > with only permission attributes set, let's simply ignore those for now. > > Contributed-under: TianoCore Contribution Agreement 1.0 > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org> > --- > ArmPkg/Drivers/CpuDxe/Arm/Mmu.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c b/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c > index b6ba975b353a..89e429925ba9 100644 > --- a/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c > +++ b/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c > @@ -680,6 +680,13 @@ SetMemoryAttributes ( > { > EFI_STATUS Status; > > + // > + // Ignore invocations that only modify permission bits > + // > + if ((Attributes & EFI_MEMORY_CACHETYPE_MASK) == 0) { > + return EFI_SUCCESS; > + } > + > if(((BaseAddress & 0xFFFFF) == 0) && ((Length & 0xFFFFF) == 0)) { > // Is the base and length a multiple of 1 MB? > DEBUG ((EFI_D_PAGE, "SetMemoryAttributes(): MMU section 0x%x length 0x%x to %lx\n", (UINTN)BaseAddress, (UINTN)Length, Attributes)); > -- > 2.7.4 > _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
diff --git a/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c b/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c index b6ba975b353a..89e429925ba9 100644 --- a/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c +++ b/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c @@ -680,6 +680,13 @@ SetMemoryAttributes ( { EFI_STATUS Status; + // + // Ignore invocations that only modify permission bits + // + if ((Attributes & EFI_MEMORY_CACHETYPE_MASK) == 0) { + return EFI_SUCCESS; + } + if(((BaseAddress & 0xFFFFF) == 0) && ((Length & 0xFFFFF) == 0)) { // Is the base and length a multiple of 1 MB? DEBUG ((EFI_D_PAGE, "SetMemoryAttributes(): MMU section 0x%x length 0x%x to %lx\n", (UINTN)BaseAddress, (UINTN)Length, Attributes));
Currently, we have not implemented support on 32-bit ARM for managing permission bits in the page tables. Since the new DXE page protection for PE/COFF images may invoke EFI_CPU_ARCH_PROTOCOL.SetMemoryAttributes() with only permission attributes set, let's simply ignore those for now. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- ArmPkg/Drivers/CpuDxe/Arm/Mmu.c | 7 +++++++ 1 file changed, 7 insertions(+) -- 2.7.4 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel