From dec0ab3bc3a26685872963534d422ac0258e4e2b Mon Sep 17 00:00:00 2001 From: Andreas Larsson Date: Fri, 5 Feb 2021 14:20:31 +0100 Subject: [PATCH] sparc32: Limit memblock allocation to low memory [ Upstream commit bda166930c37604ffa93f2425426af6921ec575a ] Commit cca079ef8ac29a7c02192d2bad2ffe4c0c5ffdd0 changed sparc32 to use memblocks instead of bootmem, but also made high memory available via memblock allocation which does not work together with e.g. phys_to_virt and can lead to kernel panic. This changes back to only low memory being allocatable in the early stages, now using memblock allocation. Signed-off-by: Andreas Larsson Acked-by: Mike Rapoport Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- arch/sparc/mm/init_32.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c index 906eda1158b4..40dd6cb4a413 100644 --- a/arch/sparc/mm/init_32.c +++ b/arch/sparc/mm/init_32.c @@ -197,6 +197,9 @@ unsigned long __init bootmem_init(unsigned long *pages_avail) size = memblock_phys_mem_size() - memblock_reserved_size(); *pages_avail = (size >> PAGE_SHIFT) - high_pages; + /* Only allow low memory to be allocated via memblock allocation */ + memblock_set_current_limit(max_low_pfn << PAGE_SHIFT); + return max_pfn; }