Re: [PATCH] regulator: core: fix error path of regulator_ena_gpio_free

From: Krzysztof Adamski
Date: Wed Feb 24 2016 - 03:27:34 EST

On Tue, Feb 23, 2016 at 03:18:59PM +0000, Jon Hunter wrote:

On 23/02/16 14:47, Krzysztof Adamski wrote:
Signed-off-by: Krzysztof Adamski <krzysztof.adamski@xxxxxxxxx>
Reported-by: Jon Hunter <jonathanh@xxxxxxxxxx>

Nit ... I think that order of the above should be reversed.

Couldn't find any reference stating proper order of those tags and briefly looking at other commit messages shows this order as quite common.

drivers/regulator/core.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 6ee9ba4..d1e7859 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -3919,7 +3919,7 @@ regulator_register(const struct regulator_desc *regulator_desc,
if (ret != 0) {
rdev_err(rdev, "Failed to request enable GPIO%d: %d\n",
config->ena_gpio, ret);
- goto wash;
+ goto clean;

@@ -3942,7 +3942,7 @@ regulator_register(const struct regulator_desc *regulator_desc,

ret = set_machine_constraints(rdev, constraints);
if (ret < 0)
- goto scrub;
+ goto wash;

if (init_data && init_data->supply_regulator)
rdev->supply_name = init_data->supply_regulator;
@@ -3972,10 +3972,8 @@ out:

- regulator_ena_gpio_free(rdev);
+ regulator_ena_gpio_free(rdev);
/* device core frees rdev */
rdev = ERR_PTR(ret);

What about the case where device_register() fails? I think you still
call clean and so you will leak the gpio?


True. I couldn't find anything more clever than calling regulator_ena_gpio_free() in two paths like in an upcomming v2. Putting it inside of regulator_dev_release() won't entirely fix the problem either as this won't be called in this particular case (device_register() fail). I personally still prefer calling regulator_ena_gpio_free() inside of regulator_register insted of deffering it to regulator_dev_release() as it seems to be clearer to me.

Best regards,
Krzysztof Adamski