On Thu, Jun 22, 2023 at 01:20:51AM +0800, linan666@xxxxxxxxxxxxxxx wrote:
> From: Li Nan <linan122@xxxxxxxxxx>
>
> badblocks will loss if we set it as below:
>
> # echo 1 1 > bad_blocks
> # echo 3 1 > bad_blocks
> # echo 1 5 > bad_blocks
> # cat bad_blocks
> 1 3
>
> In badblocks_set(), if there is an intersection between p[lo] and p[hi],
> we will combine them. The end of new badblocks is p[hi]'s end now. but
> p[lo] may cross p[hi] and new end should be the larger of p[lo] and p[hi].
Reconsider rewriting the commit log. It seems you converted code to
sentence ;-).
Also it might help to show after the patch how the above example would be
for cat bad_blocks
>
> Fixes: 9e0e252a048b ("badblocks: Add core badblock management code")
> Signed-off-by: Li Nan <linan122@xxxxxxxxxx>
> ---
> block/badblocks.c | 10 ++++------
> 1 file changed, 4 insertions(+), 6 deletions(-)
>
> diff --git a/block/badblocks.c b/block/badblocks.c
> index 7e6ebe2ac12c..2c2ef8284a3f 100644
> --- a/block/badblocks.c
> +++ b/block/badblocks.c
> @@ -267,16 +267,14 @@ int badblocks_set(struct badblocks *bb, sector_t s, int sectors,
> if (sectors == 0 && hi < bb->count) {
> /* we might be able to combine lo and hi */
> /* Note: 's' is at the end of 'lo' */
> - sector_t a = BB_OFFSET(p[hi]);
> - int lolen = BB_LEN(p[lo]);
> - int hilen = BB_LEN(p[hi]);
> - int newlen = lolen + hilen - (s - a);
> + sector_t a = BB_OFFSET(p[lo]);
> + int newlen = max(s, BB_OFFSET(p[hi]) + BB_LEN(p[hi])) - a;
>
> - if (s >= a && newlen < BB_MAX_LEN) {
> + if (s >= BB_OFFSET(p[hi]) && newlen < BB_MAX_LEN) {
> /* yes, we can combine them */
> int ack = BB_ACK(p[lo]) && BB_ACK(p[hi]);
>
> - p[lo] = BB_MAKE(BB_OFFSET(p[lo]), newlen, ack);
> + p[lo] = BB_MAKE(a, newlen, ack);
> memmove(p + hi, p + hi + 1,
> (bb->count - hi - 1) * 8);
> bb->count--;
> --
> 2.39.2
>
