summaryrefslogtreecommitdiff
path: root/mm/memblock.c
diff options
context:
space:
mode:
authorVineet Gupta <Vineet.Gupta1@synopsys.com>2013-04-29 22:06:15 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2013-04-29 22:54:28 (GMT)
commit94f3d3afb65f27d4e7b8251e323c6418982cb9c7 (patch)
tree09bf2a9c53e631aebae6cd011122089a00bb8ca6 /mm/memblock.c
parent369a713e9678227e203b53931ad1a10cd8eac811 (diff)
downloadlinux-3.10-94f3d3afb65f27d4e7b8251e323c6418982cb9c7.zip
linux-3.10-94f3d3afb65f27d4e7b8251e323c6418982cb9c7.tar.gz
linux-3.10-94f3d3afb65f27d4e7b8251e323c6418982cb9c7.tar.bz2
memblock: add assertion for zero allocation alignment
This came to light when calling memblock allocator from arc port (for copying flattended DT). If a "0" alignment is passed, the allocator round_up() call incorrectly rounds up the size to 0. round_up(num, alignto) => ((num - 1) | (alignto -1)) + 1 While the obvious allocation failure causes kernel to panic, it is better to warn the caller to fix the code. Tejun suggested that instead of BUG_ON(!align) - which might be ineffective due to pending console init and such, it is better to WARN_ON, and continue the boot with a reasonable default align. Caller passing @size need not be handled similarly as the subsequent panic will indicate that anyhow. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/memblock.c')
-rw-r--r--mm/memblock.c3
1 files changed, 3 insertions, 0 deletions
diff --git a/mm/memblock.c b/mm/memblock.c
index b8d9147..2cce8b3 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -771,6 +771,9 @@ static phys_addr_t __init memblock_alloc_base_nid(phys_addr_t size,
{
phys_addr_t found;
+ if (WARN_ON(!align))
+ align = __alignof__(long long);
+
/* align @size to avoid excessive fragmentation on reserved array */
size = round_up(size, align);