Re: [PATCH] block: bio: Trim bio to sensible size in bio_trim()

[linmiaohe]

Jens Axboe <axboe@xxxxxxxxx> wrote:
>On 8/29/20 3:37 AM, Miaohe Lin wrote:
>> Trim bio to sensible size in bio_trim() or something bad may happen.
>
>This really needs a LOT more detail. What is "something bad"? How does this condition trigger to begin with?
>

Many thanks for your reply.

I do this mainly by code review, so I didn't find the condition trigger to begin with. But I think it's better
to do such a check as this is a external Interface. Also If bio_trim() set bio->bi_iter.bi_size to a value larger than the origin one,
we may access the bio_vec past the last one of bio->bi_io_vec in for_each_bvec macro.

>--
>Jens Axboe
>