arm64/mmu: ignore debug_pagealloc for kernel segments

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The debug_pagealloc facility manipulates kernel mappings in the linear
region at page granularity to detect out of bounds or use-after-free
accesses. Since the kernel segments are not allocated dynamically,
there is no point in taking the debug_pagealloc_enabled flag into
account for them, and we can use block mappings unconditionally.

Note that this applies equally to the linear alias of text/rodata:
we will never have dynamic allocations there given that the same
memory is statically in use by the kernel image.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

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Ard Biesheuvel 2017-03-09 21:52:05 +01:00 • committed by Catalin Marinas

parent e393cf40ae

commit eccc1bff1b

1 changed files with 3 additions and 4 deletions

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arch/arm64/mm/mmu.c

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