Just like the previous, fix the possible sleep-in-atomic in regmap_register_patch() by moving the allocation out of the lock.
This makes the function unsafe for concurrent access as map->patch and map->patch_regs are changed without lock now. But such a use case must be very rare, thus we take rather simplicity over complexity, and add a note in the function description mentioning this restriction.
Signed-off-by: Takashi Iwai tiwai@suse.de --- drivers/base/regmap/regmap.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-)
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 6d134a3cbfd3..e6827cee29a3 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -2174,6 +2174,10 @@ EXPORT_SYMBOL_GPL(regmap_async_complete); * apply them immediately. Typically this is used to apply * corrections to be applied to the device defaults on startup, such * as the updates some vendors provide to undocumented registers. + * + * Note that the function gives no protection over concurrent access + * to map->patch and map->patch_regs. If needed, apply some lock in + * the caller side. */ int regmap_register_patch(struct regmap *map, const struct reg_default *regs, int num_regs) @@ -2186,6 +2190,16 @@ int regmap_register_patch(struct regmap *map, const struct reg_default *regs, num_regs)) return 0;
+ p = krealloc(map->patch, + sizeof(struct reg_default) * (map->patch_regs + num_regs), + GFP_KERNEL); + if (!p) + return -ENOMEM; + + memcpy(p + map->patch_regs, regs, num_regs * sizeof(*regs)); + map->patch = p; + map->patch_regs += num_regs; + map->lock(map->lock_arg);
bypass = map->cache_bypass; @@ -2203,17 +2217,6 @@ int regmap_register_patch(struct regmap *map, const struct reg_default *regs, } }
- p = krealloc(map->patch, - sizeof(struct reg_default) * (map->patch_regs + num_regs), - GFP_KERNEL); - if (p) { - memcpy(p + map->patch_regs, regs, num_regs * sizeof(*regs)); - map->patch = p; - map->patch_regs += num_regs; - } else { - ret = -ENOMEM; - } - out: map->async = false; map->cache_bypass = bypass;