Re: [PATCH 0/5] hwmon: (pmbus) Fix unchecked error returns in multiple drivers

[Guenter Roeck <linux@roeck-us.net>]

On Tue, Mar 17, 2026 at 05:36:33PM +0000, Pradhan, Sanman wrote:
> From: Sanman Pradhan <psanman@juniper.net>
> 
> Several PMBus device drivers use the return value of pmbus_read_word_data()
> or pmbus_read_byte_data() in arithmetic, bitwise, or macro operations
> without first checking for a negative error code. If the underlying I2C
> transaction fails, the negative errno propagates into FIELD_GET(),
> FIELD_PREP(), XOR, or DIV_ROUND_CLOSEST operations, silently producing
> corrupted sensor or status data instead of reporting the error.
> 
AI review feedback is at 
https://sashiko.dev/#/patchset/20260317174553.385567-1-sanman.pradhan%40hpe.com

One of the drivers (see patch 4 feedback) has an unrelated problem, for which
I would appreciate a fix, but patch 5/5 is making a wrong functional change
which needs to be fixed.

I'll apply patches 1..4 of the series.

Thanks,
Guenter

> Sanman Pradhan (5):
>   hwmon: (pmbus/hac300s) Add error check for pmbus_read_word_data()
>     return value
>   hwmon: (pmbus/mp2975) Add error check for pmbus_read_word_data()
>     return value
>   hwmon: (pmbus/mp2869) Check pmbus_read_byte_data() before using its
>     return value
>   hwmon: (pmbus/ina233) Add error check for pmbus_read_word_data()
>     return value
>   hwmon: (pmbus/isl68137) Fix unchecked return value and use
>     sysfs_emit()
> 
>  drivers/hwmon/pmbus/hac300s.c  |  2 ++
>  drivers/hwmon/pmbus/ina233.c   |  2 ++
>  drivers/hwmon/pmbus/isl68137.c |  7 +++++--
>  drivers/hwmon/pmbus/mp2869.c   | 35 ++++++++++++++++++++--------------
>  drivers/hwmon/pmbus/mp2975.c   |  2 ++
>  5 files changed, 32 insertions(+), 16 deletions(-)
> 
> -- 
> 2.34.1
> 
>