Re: Bug_ON with patch: bio: modify __bio_add_page() to accept pages that don't start a new segment

[Jens Axboe <axboe@kernel.dk>]

On 2014-07-16 08:51, Maurizio Lombardi wrote:
> Hi,
>
> On 07/15/2014 10:44 AM, Maurizio Lombardi wrote:
>>> I have reverted it yesterday in my tree.
>>>
>>
>>
>> The problem was here:
>>
>>          if (q->merge_bvec_fn) {
>>                  struct bvec_merge_data bvm = {
>>                          .bi_bdev = bio->bi_bdev,
>>                          .bi_sector = bio->bi_iter.bi_sector,
>>                          .bi_size = bio->bi_iter.bi_size, <-------
>>                          .bi_rw = bio->bi_rw,
>>                  };
>>
>>                  /*
>>                   * merge_bvec_fn() returns number of bytes it can accept
>>                   * at this offset
>>                   */
>>                  if (q->merge_bvec_fn(q, &bvm, bvec) < bvec->bv_len)
>>                          goto failed;
>>          }
>>
>>          /* If we may be able to merge these biovecs, force a recount */
>>          if (bio->bi_vcnt > 1 && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec)))
>>                  bio->bi_flags &= ~(1 << BIO_SEG_VALID);
>>
>>
>> it should have been ".bi_size = bio->bi_iter.bi_size - len"
>>
>
> Jens, will you restore the patch in your tree if I submit
> this fix?

Sure, we can try again, hopefully this will be the last of them.

-- 
Jens Axboe