From 3dec0fe48a8936528aae2fc3f904c2c9a34ba368 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Fri, 24 Oct 2014 18:16:47 +0100 Subject: [PATCH] arm64: Fix memblock current_limit with 64K pages and 48-bit VA With 48-bit VA space, the 64K page configuration uses 3 levels instead of 2 and PUD_SIZE != PMD_SIZE. Since with 64K pages we only cover PMD_SIZE with the initial swapper_pg_dir populated in head.S, the memblock current_limit needs to be set accordingly in map_mem() to avoid allocating unmapped memory. The memblock current_limit is progressively increased as more blocks are mapped. Signed-off-by: Catalin Marinas --- arch/arm64/mm/mmu.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 6894ef3e6234..0bf90d26e745 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -297,11 +297,15 @@ static void __init map_mem(void) * create_mapping requires puds, pmds and ptes to be allocated from * memory addressable from the initial direct kernel mapping. * - * The initial direct kernel mapping, located at swapper_pg_dir, - * gives us PUD_SIZE memory starting from PHYS_OFFSET (which must be - * aligned to 2MB as per Documentation/arm64/booting.txt). + * The initial direct kernel mapping, located at swapper_pg_dir, gives + * us PUD_SIZE (4K pages) or PMD_SIZE (64K pages) memory starting from + * PHYS_OFFSET (which must be aligned to 2MB as per + * Documentation/arm64/booting.txt). */ - limit = PHYS_OFFSET + PUD_SIZE; + if (IS_ENABLED(CONFIG_ARM64_64K_PAGES)) + limit = PHYS_OFFSET + PMD_SIZE; + else + limit = PHYS_OFFSET + PUD_SIZE; memblock_set_current_limit(limit); /* map all the memory banks */ -- 2.34.1