Commit fa938953 authored Jan 25, 2006 by Michael Ellerman Committed by Paul Mackerras Feb 07, 2006

[PATCH] powerpc: Don't allocate zero bytes in finish_device_tree()

In prom.c we run finish_node() on allnodes twice. The first time we just
calculate how much memory we'll need, the second time we do the actual work.

If the calculation stage determines that we need 0 bytes, then we should skip
the lmb allocation. Although an alloc of zero will work, it has been seen to
lead to a BUG_ON() in reserve_bootmem() on at least one machine.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

parent 3ea4807d

arch/powerpc/kernel/prom.c

+6 −1

Original line number	Diff line number	Diff line
		@@ -491,7 +491,12 @@ void __init finish_device_tree(void)
		size = 16;
		finish_node(allnodes, &size, 1);
		size -= 16;

		if (0 == size)
		end = start = 0;
		else
		end = start = (unsigned long)__va(lmb_alloc(size, 128));

		finish_node(allnodes, &end, 0);
		BUG_ON(end != start + size);