From f921f53e089a12a192808ac4319f28727b35dc0f Mon Sep 17 00:00:00 2001 From: Mike Rapoport Date: Mon, 17 May 2021 21:31:59 +0300 Subject: [PATCH] memblock: align freed memory map on pageblock boundaries with SPARSEMEM When CONFIG_SPARSEMEM=y the ranges of the memory map that are freed are not aligned to the pageblock boundaries which breaks assumptions about homogeneity of the memory map throughout core mm code. Make sure that the freed memory map is always aligned on pageblock boundaries regardless of the memory model selection. Signed-off-by: Mike Rapoport Tested-by: Tony Lindgren --- mm/memblock.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/mm/memblock.c b/mm/memblock.c index 97fa87541b5f..2e25d69739e0 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -1941,14 +1941,13 @@ static void __init free_unused_memmap(void) * due to SPARSEMEM sections which aren't present. */ start = min(start, ALIGN(prev_end, PAGES_PER_SECTION)); -#else +#endif /* * Align down here since many operations in VM subsystem * presume that there are no holes in the memory map inside * a pageblock */ start = round_down(start, pageblock_nr_pages); -#endif /* * If we had a previous bank, and there is a space @@ -1966,8 +1965,10 @@ static void __init free_unused_memmap(void) } #ifdef CONFIG_SPARSEMEM - if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION)) + if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION)) { + prev_end = ALIGN(end, pageblock_nr_pages); free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION)); + } #endif } -- GitLab