Commit e64681b4 authored Nov 13, 2019 by Max Filippov

xtensa: use MEMBLOCK_ALLOC_ANYWHERE for KASAN shadow map



KASAN shadow map doesn't need to be accessible through the linear kernel
mapping, allocate its pages with MEMBLOCK_ALLOC_ANYWHERE so that high
memory can be used. This frees up to ~100MB of low memory on xtensa
configurations with KASAN and high memory.

Cc: stable@vger.kernel.org # v5.1+
Fixes: f240ec09 ("memblock: replace memblock_alloc_base(ANYWHERE) with memblock_phys_alloc")
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

parent 36de10c4

arch/xtensa/mm/kasan_init.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -60,7 +60,9 @@ static void __init populate(void start, void end)

		for (k = 0; k < PTRS_PER_PTE; ++k, ++j) {
		phys_addr_t phys =
		memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
		memblock_phys_alloc_range(PAGE_SIZE, PAGE_SIZE,
		0,
		MEMBLOCK_ALLOC_ANYWHERE);

		if (!phys)
		panic("Failed to allocate page table page\n");

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