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From:   linan666@huaweicloud.com
To:     axboe@kernel.dk, linan122@huawei.com, vishal.l.verma@intel.com,
        dan.j.williams@intel.com, ashok_raj@linux.intel.com
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        yukuai3@huawei.com, yi.zhang@huawei.com, houtao1@huawei.com,
        yangerkun@huawei.com
Subject: [PATCH v4 4/4] block/badblocks: fix the bug of reverse order
Date:   Mon, 26 Jun 2023 16:09:13 +0800
Message-Id: <20230626080913.3493135-5-linan666@huaweicloud.com>
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From: Li Nan <linan122@huawei.com>

Badblocks are arranged from small to large, but order of badblocks will
be reversed if we set a large area at once as below:
  $ echo 0 2048 > bad_blocks
  $ cat bad_blocks
    1536 512
    1024 512
    512 512
    0 512

Actually, it should be:
  $ echo 0 2048 > bad_blocks
  $ cat bad_blocks
    0 512
    512 512
    1024 512
    1536 512

'hi' remains unchanged while setting continuous badblocks is wrong, the
next badblocks is greater than 'p[hi]', and it should be added to
'p[hi+1]'. Let 'hi' +1 each cycle.

  (0 512)				0	 512
  |_________|				|_________|
     p[hi]				   p[hi]

  (512 512) (0 512)		 fix	0	 512	   1024
  |_________|_________|		 ===>	|_________|_________|
     p[hi]					    p[hi+1]

  (1024 512)(512 512) (0 512)		0	 512	   1024	     1536
  |_________|_________|_________|	|_________|_________|_________|
     p[hi]						      p[hi+2]

  ...

Fixes: 9e0e252a048b ("badblocks: Add core badblock management code")
Signed-off-by: Li Nan <linan122@huawei.com>
---
 block/badblocks.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/block/badblocks.c b/block/badblocks.c
index c1745b76d8f1..b79d37a4bf0e 100644
--- a/block/badblocks.c
+++ b/block/badblocks.c
@@ -301,6 +301,7 @@ int badblocks_set(struct badblocks *bb, sector_t s, int sectors,
 			p[hi] = BB_MAKE(s, this_sectors, acknowledged);
 			sectors -= this_sectors;
 			s += this_sectors;
+			hi++;
 			changed = true;
 		}
 	}
-- 
2.39.2