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| author | Vineet Gupta <Vineet.Gupta1@synopsys.com> | 2013-04-29 15:06:15 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-04-29 15:54:28 -0700 |
| commit | 94f3d3afb65f27d4e7b8251e323c6418982cb9c7 (patch) | |
| tree | 09bf2a9c53e631aebae6cd011122089a00bb8ca6 /mm | |
| parent | 369a713e9678227e203b53931ad1a10cd8eac811 (diff) | |
| download | linux-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')
| -rw-r--r-- | mm/memblock.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/mm/memblock.c b/mm/memblock.c index b8d9147e5c08..2cce8b3e76ed 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); |