Hi Andrew,
On Friday 22 February 2013 02:23 AM, Tejun Heo wrote:
> On Thu, Feb 21, 2013 at 12:52 PM, Vineet Gupta
> <[email protected]> wrote:
>> 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 <[email protected]>
>> Cc: Andrew Morton <[email protected]>
>> Cc: Tejun Heo <[email protected]>
>> Cc: Yinghai Lu <[email protected]>
>> Cc: Wanpeng Li <[email protected]>
>> Cc: Ingo Molnar <[email protected]>
>> Cc: [email protected]
>> Cc: [email protected]
>
> Acked-by: Tejun Heo <[email protected]>
>
> Thanks.
>
I'm hoping this will be routed via the mm tree.
Thx,
-Vineet