From: Nikita Yushchenko Date: Thu, 22 Sep 2016 09:02:25 +0000 (+0300) Subject: regmap: fix deadlock on _regmap_raw_write() error path X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=f0aa1ce6259eb65f53f969b3250c1d0aac84f30b;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git regmap: fix deadlock on _regmap_raw_write() error path Commit 815806e39bf6 ("regmap: drop cache if the bus transfer error") added a call to regcache_drop_region() to error path in _regmap_raw_write(). However that path runs with regmap lock taken, and regcache_drop_region() tries to re-take it, causing a deadlock. Fix that by calling map->cache_ops->drop() directly. Signed-off-by: Nikita Yushchenko Signed-off-by: Mark Brown --- diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 25d26bb18970..e964d068874d 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -1475,7 +1475,11 @@ int _regmap_raw_write(struct regmap *map, unsigned int reg, kfree(buf); } else if (ret != 0 && !map->cache_bypass && map->format.parse_val) { - regcache_drop_region(map, reg, reg + 1); + /* regcache_drop_region() takes lock that we already have, + * thus call map->cache_ops->drop() directly + */ + if (map->cache_ops && map->cache_ops->drop) + map->cache_ops->drop(map, reg, reg + 1); } trace_regmap_hw_write_done(map, reg, val_len / map->format.val_bytes);