mm/memblock.c: warn if zero alignment was requested (2f770806) · Commits · 戴 / test

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:

mm/memblock.c

+11 −0

Original line number	Original line	Diff line number	Diff line
	@@ -1247,6 +1247,12 @@ static phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size,
	{		{
	phys_addr_t found;		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,		found = memblock_find_in_range_node(size, align, start, end, nid,
	flags);		flags);
	if (found && !memblock_reserve(found, size)) {		if (found && !memblock_reserve(found, size)) {
	@@ -1369,6 +1375,11 @@ static void * __init memblock_alloc_internal(
	if (WARN_ON_ONCE(slab_is_available()))		if (WARN_ON_ONCE(slab_is_available()))
	return kzalloc_node(size, GFP_NOWAIT, nid);		return kzalloc_node(size, GFP_NOWAIT, nid);

			if (!align) {
			dump_stack();
			align = SMP_CACHE_BYTES;
			}

	if (max_addr > memblock.current_limit)		if (max_addr > memblock.current_limit)
	max_addr = memblock.current_limit;		max_addr = memblock.current_limit;
	again:		again: