[PATCH v2 0/9] fix max discard sectors limit

[Namjae Jeon]

2013/4/23, Kent Overstreet <koverstreet at google.com>:
> On Sat, Apr 20, 2013 at 01:40:02AM +0900, Namjae Jeon wrote:
>> From: Namjae Jeon <namjae.jeon at samsung.com>
>>
>> linux-v3.8-rc1 and later support for plug for blkdev_issue_discard with
>> commit 0cfbcafcae8b7364b5fa96c2b26ccde7a3a296a9
>> (block: add plug for blkdev_issue_discard )
>>
>> For example,
>> 1) DISCARD rq-1 with size size 4GB
>> 2) DISCARD rq-2 with size size 1GB
>>
>> If these 2 discard requests get merged, final request size will be 5GB.
>>
>> In this case, request's __data_len field may overflow as it can store
>> max 4GB(unsigned int).
>
> Complete NACK - like James said, this fix is nonsensical. This should be
> fixed by just checking for overflow before merging requests, not with
> weird hacks in the drivers.
that agree to your opinion, and will change at only appropriate
place(James'change) and will send the updated patch soon.
Thanks.
>