diff options
| author | Abdurrahman Hussain <abdurrahman@nexthop.ai> | 2026-05-18 17:52:32 -0700 |
|---|---|---|
| committer | Guenter Roeck <linux@roeck-us.net> | 2026-05-21 07:00:39 -0700 |
| commit | 4e4af55aaca7f6d7673d5f9889ad0529db86a048 (patch) | |
| tree | 9a3c16cfb7255834bd81d4cea29ceadaa620e408 | |
| parent | 9f1dd8f9491eb840cbea7ffdf4cad031e25f8ae0 (diff) | |
hwmon: (pmbus/adm1266) serialize sequencer_state debugfs read with pmbus_lock
adm1266_state_read() backs the sequencer_state debugfs entry and
issues an i2c_smbus_read_word_data(client, ADM1266_READ_STATE)
against the device without taking pmbus_lock. pmbus_core holds
pmbus_lock around its own multi-transaction sequences (notably the
"set PAGE, then read paged register" pattern used by hwmon
attributes), so an unlocked debugfs reader can land between a PAGE
write and the subsequent paged read in another thread. READ_STATE
itself is not paged, so it cannot corrupt PAGE in flight, but the
same defensive serialisation that applies to the GPIO accessors
applies here: any direct device access from outside pmbus_core
should be ordered with respect to pmbus_core's own.
Take pmbus_lock at the top of adm1266_state_read() via the
scope-based guard().
Fixes: ed1ff457e187 ("hwmon: (pmbus/adm1266) add debugfs for states")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-8-e425e4f88139@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
| -rw-r--r-- | drivers/hwmon/pmbus/adm1266.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/hwmon/pmbus/adm1266.c b/drivers/hwmon/pmbus/adm1266.c index 5ddca5701032..6f6ad7b20e9a 100644 --- a/drivers/hwmon/pmbus/adm1266.c +++ b/drivers/hwmon/pmbus/adm1266.c @@ -335,6 +335,7 @@ static int adm1266_state_read(struct seq_file *s, void *pdata) struct i2c_client *client = to_i2c_client(dev); int ret; + guard(pmbus_lock)(client); ret = i2c_smbus_read_word_data(client, ADM1266_READ_STATE); if (ret < 0) return ret; |