Re: [PATCH V7 10/24] block: introduce multipage page bvec helpers
From: Ming Lei
Date: Fri Nov 09 2018 - 06:15:36 EST
On Wed, Jun 27, 2018 at 11:59:37PM +0800, kbuild test robot wrote:
> Hi Ming,
>
> Thank you for the patch! Perhaps something to improve:
>
> [auto build test WARNING on linus/master]
> [also build test WARNING on v4.18-rc2]
> [cannot apply to next-20180627]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>
> url: https://github.com/0day-ci/linux/commits/Ming-Lei/block-support-multipage-bvec/20180627-214022
> reproduce:
> # apt-get install sparse
> make ARCH=x86_64 allmodconfig
> make C=1 CF=-D__CHECK_ENDIAN__
>
>
> sparse warnings: (new ones prefixed by >>)
>
> net/ceph/messenger.c:842:25: sparse: expression using sizeof(void)
> net/ceph/messenger.c:842:25: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:847:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:848:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:855:29: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:869:9: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:139:37: sparse: expression using sizeof(void)
> include/linux/bvec.h:140:32: sparse: expression using sizeof(void)
> include/linux/bvec.h:140:32: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:889:9: sparse: expression using sizeof(void)
> net/ceph/messenger.c:890:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:890:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:890:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:890:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:890:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:890:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:890:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:890:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:890:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:890:47: sparse: expression using sizeof(void)
> net/ceph/messenger.c:890:47: sparse: expression using sizeof(void)
> >> net/ceph/messenger.c:890:47: sparse: too many warnings
>
> vim +890 net/ceph/messenger.c
>
> 6aaa4511 Alex Elder 2013-03-06 862
> 8ae4f4f5 Alex Elder 2013-03-14 863 static bool ceph_msg_data_bio_advance(struct ceph_msg_data_cursor *cursor,
> 8ae4f4f5 Alex Elder 2013-03-14 864 size_t bytes)
> 6aaa4511 Alex Elder 2013-03-06 865 {
> 5359a17d Ilya Dryomov 2018-01-20 866 struct ceph_bio_iter *it = &cursor->bio_iter;
> 6aaa4511 Alex Elder 2013-03-06 867
> 5359a17d Ilya Dryomov 2018-01-20 868 BUG_ON(bytes > cursor->resid);
> 5359a17d Ilya Dryomov 2018-01-20 869 BUG_ON(bytes > bio_iter_len(it->bio, it->iter));
> 25aff7c5 Alex Elder 2013-03-11 870 cursor->resid -= bytes;
> 5359a17d Ilya Dryomov 2018-01-20 871 bio_advance_iter(it->bio, &it->iter, bytes);
> f38a5181 Kent Overstreet 2013-08-07 872
> 5359a17d Ilya Dryomov 2018-01-20 873 if (!cursor->resid) {
> 5359a17d Ilya Dryomov 2018-01-20 874 BUG_ON(!cursor->last_piece);
> 5359a17d Ilya Dryomov 2018-01-20 875 return false; /* no more data */
> 5359a17d Ilya Dryomov 2018-01-20 876 }
> f38a5181 Kent Overstreet 2013-08-07 877
> 5359a17d Ilya Dryomov 2018-01-20 878 if (!bytes || (it->iter.bi_size && it->iter.bi_bvec_done))
> 6aaa4511 Alex Elder 2013-03-06 879 return false; /* more bytes to process in this segment */
> 6aaa4511 Alex Elder 2013-03-06 880
> 5359a17d Ilya Dryomov 2018-01-20 881 if (!it->iter.bi_size) {
> 5359a17d Ilya Dryomov 2018-01-20 882 it->bio = it->bio->bi_next;
> 5359a17d Ilya Dryomov 2018-01-20 883 it->iter = it->bio->bi_iter;
> 5359a17d Ilya Dryomov 2018-01-20 884 if (cursor->resid < it->iter.bi_size)
> 5359a17d Ilya Dryomov 2018-01-20 885 it->iter.bi_size = cursor->resid;
> 25aff7c5 Alex Elder 2013-03-11 886 }
> 6aaa4511 Alex Elder 2013-03-06 887
> 5359a17d Ilya Dryomov 2018-01-20 888 BUG_ON(cursor->last_piece);
> 5359a17d Ilya Dryomov 2018-01-20 889 BUG_ON(cursor->resid < bio_iter_len(it->bio, it->iter));
> 5359a17d Ilya Dryomov 2018-01-20 @890 cursor->last_piece = cursor->resid == bio_iter_len(it->bio, it->iter);
> 6aaa4511 Alex Elder 2013-03-06 891 return true;
> 6aaa4511 Alex Elder 2013-03-06 892 }
> ea96571f Alex Elder 2013-04-05 893 #endif /* CONFIG_BLOCK */
> df6ad1f9 Alex Elder 2012-06-11 894
>
> :::::: The code at line 890 was first introduced by commit
> :::::: 5359a17d2706b86da2af83027343d5eb256f7670 libceph, rbd: new bio handling code (aka don't clone bios)
>
> :::::: TO: Ilya Dryomov <idryomov@xxxxxxxxx>
> :::::: CC: Ilya Dryomov <idryomov@xxxxxxxxx>
>
> ---
> 0-DAY kernel test infrastructure Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all Intel Corporation
Actually this sparse warning on bio_iter_len() can be triggered without this patch
too. This patch changes code in bvec.h, just causes the warned line changed.
thanks,
Ming