[PATCH 0/3] Free up a couple of MAIRs

Will Deacon will at kernel.org
Thu May 6 02:50:31 PDT 2021


Hi folks,

Catalin pointed out that the Device-GRE memory type is unused, despite
having a MAIR allocation. In removing that, I noticed that we also
allocate Normal-WT despite it only being used for EFI_MEMORY_WT mappings,
which can use Normal-NC instead.

With these changes, we free up a couple of MAIR entries for more
interesting things (e.g. outer cacheability attributes if we need them
in future for the SLC).

Patches taken against the arm64 for-next/core branch.

Cheers,

Will

Cc: Christoph Hellwig <hch at lst.de>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Ard Biesheuvel <ardb at kernel.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>

--->8

Will Deacon (3):
  arm64: mm: Remove unused support for Device-GRE memory type
  arm64: acpi: Map EFI_MEMORY_WT memory as Normal-NC
  arm64: mm: Remove unused support for Normal-WT memory type

 arch/arm64/include/asm/memory.h       |  6 ++----
 arch/arm64/include/asm/pgtable-prot.h |  1 -
 arch/arm64/include/asm/sysreg.h       |  2 --
 arch/arm64/kernel/acpi.c              | 10 +++-------
 arch/arm64/mm/proc.S                  |  2 --
 arch/arm64/mm/ptdump.c                |  4 ----
 6 files changed, 5 insertions(+), 20 deletions(-)

-- 
2.31.1.607.g51e8a6a459-goog




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