From 2f770806fd2c3db9616965e57ba60d80f43c827d Mon Sep 17 00:00:00 2001 From: Mike Rapoport Date: Tue, 30 Oct 2018 15:10:01 -0700 Subject: [PATCH] mm/memblock.c: warn if zero alignment was requested After updating all memblock users to explicitly specify SMP_CACHE_BYTES alignment rather than use 0, it is still possible that uncovered users may sneak in. Add a WARN_ON_ONCE for such cases. [sfr@canb.auug.org.au: use dump_stack() instead of WARN_ON_ONCE for the alignment checks] Link: http://lkml.kernel.org/r/20181016131927.6ceba6ab@canb.auug.org.au [akpm@linux-foundation.org: add apologetic comment] Link: http://lkml.kernel.org/r/20181011060850.GA19822@rapoport-lnx Signed-off-by: Mike Rapoport Signed-off-by: Stephen Rothwell Reviewed-by: Andrew Morton Acked-by: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memblock.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/mm/memblock.c b/mm/memblock.c index 839531133816..7df468c8ebc8 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -1247,6 +1247,12 @@ static phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size, { phys_addr_t found; + if (!align) { + /* Can't use WARNs this early in boot on powerpc */ + dump_stack(); + align = SMP_CACHE_BYTES; + } + found = memblock_find_in_range_node(size, align, start, end, nid, flags); if (found && !memblock_reserve(found, size)) { @@ -1369,6 +1375,11 @@ static void * __init memblock_alloc_internal( if (WARN_ON_ONCE(slab_is_available())) return kzalloc_node(size, GFP_NOWAIT, nid); + if (!align) { + dump_stack(); + align = SMP_CACHE_BYTES; + } + if (max_addr > memblock.current_limit) max_addr = memblock.current_limit; again: