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 <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Mva address calculation should use the left-shifted current
section index instead of the left-shifted table base address.
Using the table base address here has the side-effect of potentially
causing an access violation depending on the base address value.
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Christopher Co <christopher.co@microsoft.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Given that these days, our ARM port only supports ARMv7 and later, we
can assume that the page table walker's memory accesses are cache
coherent, and so there is no need to perform cache maintenance. It
does require the page tables themselves to reside in memory mapped as
writeback cacheable so ASSERT() that this is the case.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Peculiarly enough, the current page table manipulation code takes it
upon itself to write back and invalidate the memory contents covered
by page and section mappings when their memory attributes change. It
is not generally the case that data must be written back when such a
change occurs, even when switching from cacheable to non-cacheable
attributes, and in some cases, it is actually causing problems. (The
cache maintenance is also performed on the PCIe MMIO regions as they
get mapped by the PCI bus driver, and under virtualization, each
cache maintenance operation on an emulated MMIO region triggers a
round trip to the host and back)
So let's just drop this code.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
From what I can see this bug dates back to the commit from 2011 where
support for this was added: 2cf4b60895
The first problem is that PopulateLevel2PageTable overflows the
translation table buffer because it doesn't verify that the size
actually fits within one level 2 page table.
The second problem is that the loop in FillTranslationTable doesn't
care about the PhysicalBase or the RemainLength and always substracts
one section size from RemainLength.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Michael Zimmermann <sigmaepsilon92@gmail.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Now that we have the prerequisite functionality available in ArmMmuLib,
wire it up into ArmSetMemoryRegionNoExec, ArmClearMemoryRegionNoExec,
ArmSetMemoryRegionReadOnly and ArmClearMemoryRegionReadOnly. This is
used by the non-executable stack feature that is configured by DxeIpl.
NOTE: The current implementation will not combine RO and XP attributes,
i.e., setting/clearing a region no-exec will unconditionally
clear the read-only attribute, and vice versa. Currently, we
only use ArmSetMemoryRegionNoExec(), so for now, we should be
able to live with this.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
We no longer make use of the ArmMmuLib 'feature' to create aliased
memory ranges with mismatched attributes, and in fact, it was only
wired up in the ARM version to begin with.
So remove the VirtualMask argument from ArmSetMemoryAttributes()'s
prototype, and remove the dead code that referred to it.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
... where it belongs, since AARCH64 already keeps it there, and
non DXE users of ArmMmuLib (such as DxeIpl, for the non-executable
stack) may need its functionality as well.
While at it, rename SetMemoryAttributes to ArmSetMemoryAttributes,
and make any functions that are not exported STATIC. Also, replace
an explicit gBS->AllocatePages() call [which is DXE specific] with
MemoryAllocationLib::AllocatePages().
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
The routines ArmConfigureMmu(), SetMemoryAttributes() [*] and the
various set/clear read-only/no-exec routines are declared as returning
EFI_STATUS in the respective header files, so align the definitions with
that.
* SetMemoryAttributes() is declared in the wrong header (and defined in
ArmMmuLib for AARCH64 and in CpuDxe for ARM)
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
This base library encapsulates the MMU manipulation routines that have been
factored out of ArmLib. The functionality covers initial creation of the 1:1
mapping in the page tables, and remapping regions to change permissions or
cacheability attributes.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Ard Biesheuvel
Chris Co
Michael Zimmermann