[PATCH] regmap: regcache-rbtree: Fix present bitmap resize

[PATCH] regmap: regcache-rbtree: Fix present bitmap resize

[Lars-Peter Clausen]

When inserting a new register into a block at the lower end the present
bitmap is currently shifted into the wrong direction. The effect of this is
that the bitmap becomes corrupted and registers which are present might be
reported as not present and vice versa.

Fix this by shifting left rather than right.

Fixes: 472fdec7380c("regmap: rbtree: Reduce number of nodes, take 2")
Reported-by: Daniel Baluta <daniel.baluta@gmail.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/base/regmap/regcache-rbtree.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/base/regmap/regcache-rbtree.c b/drivers/base/regmap/regcache-rbtree.c
index d453a2c..81751a4 100644
--- a/drivers/base/regmap/regcache-rbtree.c
+++ b/drivers/base/regmap/regcache-rbtree.c
@@ -307,7 +307,7 @@ static int regcache_rbtree_insert_to_block(struct regmap *map,
 	if (pos == 0) {
 		memmove(blk + offset * map->cache_word_size,
 			blk, rbnode->blklen * map->cache_word_size);
-		bitmap_shift_right(present, present, offset, blklen);
+		bitmap_shift_left(present, present, offset, blklen);
 	}
 
 	/* update the rbnode block, its size and the base register */
-- 
1.8.0

Re: [PATCH] regmap: regcache-rbtree: Fix present bitmap resize

[Mark Brown]

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On Sat, Mar 07, 2015 at 05:10:01PM +0100, Lars-Peter Clausen wrote:
> When inserting a new register into a block at the lower end the present
> bitmap is currently shifted into the wrong direction. The effect of this is
> that the bitmap becomes corrupted and registers which are present might be
> reported as not present and vice versa.

Applied, thanks.

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Re: [PATCH] regmap: regcache-rbtree: Fix present bitmap resize

[Daniel Baluta]

On Sat, Mar 7, 2015 at 6:10 PM, Lars-Peter Clausen <lars@metafoo.de> wrote:
> When inserting a new register into a block at the lower end the present
> bitmap is currently shifted into the wrong direction. The effect of this is
> that the bitmap becomes corrupted and registers which are present might be
> reported as not present and vice versa.
>
> Fix this by shifting left rather than right.
>
> Fixes: 472fdec7380c("regmap: rbtree: Reduce number of nodes, take 2")
> Reported-by: Daniel Baluta <daniel.baluta@gmail.com>
> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>

Thanks Lars! I confirm that this fixes the problem :).

Daniel.