Messages in this thread Patch in this message | | | From | Anthony Olech <> | Date | Wed, 9 Oct 2013 17:44:38 +0100 | Subject | [PATCH V1] Fix Regmap Block Write single-rw Mutex Deadlock |
| |
This patch is relative to linux-next repository tag next-20130927
When regmap_bulk_write() is called with the map->use_single_rw flag set an immediate mutex deadlock happens because regmap_raw_write() is called after obtaining the mutex and regmap_raw_write() itself then tries to obtain the mutex as well.
It is obvious that no one other than myself tried it with a real device. I did, but only for the purposes of an experiment and demonstration.
But even if this situation will never ever happen with a real device, it is a bug and therefore should be fixed.
Signed-off-by: Anthony Olech <anthony.olech.opensource@diasemi.com> --- drivers/base/regmap/regmap.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 00152bf..6bd9294 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -1488,10 +1488,11 @@ int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val, */ if (map->use_single_rw) { for (i = 0; i < val_count; i++) { - ret = regmap_raw_write(map, - reg + (i * map->reg_stride), - val + (i * val_bytes), - val_bytes); + ret = _regmap_raw_write(map, + reg + (i * map->reg_stride), + val + (i * val_bytes), + val_bytes, + false); if (ret != 0) return ret; } -- end-of-patch for Fix Regmap Block Write single-rw Mutex Deadlock V1
| |