* FAILED: patch "[PATCH] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with" failed to apply to 6.6-stable tree
@ 2026-05-28 13:39 gregkh
2026-06-01 20:28 ` [PATCH 6.6.y] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with pmbus_lock Sasha Levin
2026-06-02 2:06 ` Sasha Levin
0 siblings, 2 replies; 4+ messages in thread
From: gregkh @ 2026-05-28 13:39 UTC (permalink / raw)
To: abdurrahman, bartosz.golaszewski, linux; +Cc: stable
The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x bab8c6fb5af8df7e753d196c1262cb78e92ca872
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026052831-abreast-slurp-dabc@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From bab8c6fb5af8df7e753d196c1262cb78e92ca872 Mon Sep 17 00:00:00 2001
From: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Date: Mon, 18 May 2026 17:52:30 -0700
Subject: [PATCH] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with
pmbus_lock
adm1266_gpio_get(), adm1266_gpio_get_multiple(), and
adm1266_gpio_dbg_show() all issue PMBus reads against the device but
none of them take pmbus_lock. The pmbus_core framework 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 GPIO accessor can land between a PAGE
write and the subsequent paged read in another thread and corrupt
either side's view of the device state machine.
Take pmbus_lock at the top of each of the three accessors via the
scope-based guard(). The lock is uncontended in the common case and
adds only a single mutex round-trip per call.
Fixes: d98dfad35c38 ("hwmon: (pmbus/adm1266) Add support for GPIOs")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-6-e425e4f88139@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
diff --git a/drivers/hwmon/pmbus/adm1266.c b/drivers/hwmon/pmbus/adm1266.c
index 3e8f2619cb9b..0eef58dd69a6 100644
--- a/drivers/hwmon/pmbus/adm1266.c
+++ b/drivers/hwmon/pmbus/adm1266.c
@@ -173,6 +173,8 @@ static int adm1266_gpio_get(struct gpio_chip *chip, unsigned int offset)
else
pmbus_cmd = ADM1266_PDIO_STATUS;
+ guard(pmbus_lock)(data->client);
+
ret = i2c_smbus_read_block_data(data->client, pmbus_cmd, read_buf);
if (ret < 0)
return ret;
@@ -195,6 +197,8 @@ static int adm1266_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask
unsigned int gpio_nr;
int ret;
+ guard(pmbus_lock)(data->client);
+
ret = i2c_smbus_read_block_data(data->client, ADM1266_GPIO_STATUS, read_buf);
if (ret < 0)
return ret;
@@ -236,6 +240,8 @@ static void adm1266_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
int ret;
int i;
+ guard(pmbus_lock)(data->client);
+
for (i = 0; i < ADM1266_GPIO_NR; i++) {
write_cmd = adm1266_gpio_mapping[i][1];
ret = adm1266_pmbus_block_xfer(data, ADM1266_GPIO_CONFIG, 1, &write_cmd, read_buf);
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 6.6.y] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with pmbus_lock
2026-05-28 13:39 FAILED: patch "[PATCH] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with" failed to apply to 6.6-stable tree gregkh
@ 2026-06-01 20:28 ` Sasha Levin
2026-06-02 2:06 ` Sasha Levin
1 sibling, 0 replies; 4+ messages in thread
From: Sasha Levin @ 2026-06-01 20:28 UTC (permalink / raw)
To: stable; +Cc: Abdurrahman Hussain, Bartosz Golaszewski, Guenter Roeck,
Sasha Levin
From: Abdurrahman Hussain <abdurrahman@nexthop.ai>
[ Upstream commit bab8c6fb5af8df7e753d196c1262cb78e92ca872 ]
adm1266_gpio_get(), adm1266_gpio_get_multiple(), and
adm1266_gpio_dbg_show() all issue PMBus reads against the device but
none of them take pmbus_lock. The pmbus_core framework 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 GPIO accessor can land between a PAGE
write and the subsequent paged read in another thread and corrupt
either side's view of the device state machine.
Take pmbus_lock at the top of each of the three accessors via the
scope-based guard(). The lock is uncontended in the common case and
adds only a single mutex round-trip per call.
Fixes: d98dfad35c38 ("hwmon: (pmbus/adm1266) Add support for GPIOs")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-6-e425e4f88139@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
[ open-coded each `guard(pmbus_lock)(data->client)` as explicit `pmbus_lock_interruptible()`/`pmbus_unlock()` ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/hwmon/pmbus/adm1266.c | 40 +++++++++++++++++++++++++++++------
1 file changed, 34 insertions(+), 6 deletions(-)
diff --git a/drivers/hwmon/pmbus/adm1266.c b/drivers/hwmon/pmbus/adm1266.c
index a8690d6c9b9cb0..518eaf07a123de 100644
--- a/drivers/hwmon/pmbus/adm1266.c
+++ b/drivers/hwmon/pmbus/adm1266.c
@@ -173,7 +173,12 @@ static int adm1266_gpio_get(struct gpio_chip *chip, unsigned int offset)
else
pmbus_cmd = ADM1266_PDIO_STATUS;
+ ret = pmbus_lock_interruptible(data->client);
+ if (ret)
+ return ret;
+
ret = i2c_smbus_read_block_data(data->client, pmbus_cmd, read_buf);
+ pmbus_unlock(data->client);
if (ret < 0)
return ret;
if (ret < 2)
@@ -195,11 +200,19 @@ static int adm1266_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask
unsigned int gpio_nr;
int ret;
+ ret = pmbus_lock_interruptible(data->client);
+ if (ret)
+ return ret;
+
ret = i2c_smbus_read_block_data(data->client, ADM1266_GPIO_STATUS, read_buf);
- if (ret < 0)
+ if (ret < 0) {
+ pmbus_unlock(data->client);
return ret;
- if (ret < 2)
+ }
+ if (ret < 2) {
+ pmbus_unlock(data->client);
return -EIO;
+ }
status = read_buf[0] + (read_buf[1] << 8);
@@ -210,10 +223,14 @@ static int adm1266_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask
}
ret = i2c_smbus_read_block_data(data->client, ADM1266_PDIO_STATUS, read_buf);
- if (ret < 0)
+ if (ret < 0) {
+ pmbus_unlock(data->client);
return ret;
- if (ret < 2)
+ }
+ if (ret < 2) {
+ pmbus_unlock(data->client);
return -EIO;
+ }
status = read_buf[0] + (read_buf[1] << 8);
@@ -222,6 +239,8 @@ static int adm1266_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask
set_bit(gpio_nr, bits);
}
+ pmbus_unlock(data->client);
+
return 0;
}
@@ -236,11 +255,16 @@ static void adm1266_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
int ret;
int i;
+ if (pmbus_lock_interruptible(data->client))
+ return;
+
for (i = 0; i < ADM1266_GPIO_NR; i++) {
write_cmd = adm1266_gpio_mapping[i][1];
ret = adm1266_pmbus_block_xfer(data, ADM1266_GPIO_CONFIG, 1, &write_cmd, read_buf);
- if (ret != 2)
+ if (ret != 2) {
+ pmbus_unlock(data->client);
return;
+ }
gpio_config = read_buf[0];
seq_puts(s, adm1266_names[i]);
@@ -262,8 +286,10 @@ static void adm1266_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
write_cmd = 0xFF;
ret = adm1266_pmbus_block_xfer(data, ADM1266_PDIO_CONFIG, 1, &write_cmd, read_buf);
- if (ret != 32)
+ if (ret != 32) {
+ pmbus_unlock(data->client);
return;
+ }
for (i = 0; i < ADM1266_PDIO_NR; i++) {
seq_puts(s, adm1266_names[ADM1266_GPIO_NR + i]);
@@ -286,6 +312,8 @@ static void adm1266_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
seq_puts(s, ")\n");
}
+
+ pmbus_unlock(data->client);
}
static int adm1266_config_gpio(struct adm1266_data *data)
--
2.53.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 6.6.y] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with pmbus_lock
2026-05-28 13:39 FAILED: patch "[PATCH] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with" failed to apply to 6.6-stable tree gregkh
2026-06-01 20:28 ` [PATCH 6.6.y] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with pmbus_lock Sasha Levin
@ 2026-06-02 2:06 ` Sasha Levin
2026-06-04 0:05 ` Sasha Levin
1 sibling, 1 reply; 4+ messages in thread
From: Sasha Levin @ 2026-06-02 2:06 UTC (permalink / raw)
To: stable; +Cc: Abdurrahman Hussain, Bartosz Golaszewski, Guenter Roeck,
Sasha Levin
From: Abdurrahman Hussain <abdurrahman@nexthop.ai>
[ Upstream commit bab8c6fb5af8df7e753d196c1262cb78e92ca872 ]
adm1266_gpio_get(), adm1266_gpio_get_multiple(), and
adm1266_gpio_dbg_show() all issue PMBus reads against the device but
none of them take pmbus_lock. The pmbus_core framework 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 GPIO accessor can land between a PAGE
write and the subsequent paged read in another thread and corrupt
either side's view of the device state machine.
Take pmbus_lock at the top of each of the three accessors via the
scope-based guard(). The lock is uncontended in the common case and
adds only a single mutex round-trip per call.
Fixes: d98dfad35c38 ("hwmon: (pmbus/adm1266) Add support for GPIOs")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-6-e425e4f88139@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
[ open-coded `guard(pmbus_lock)()` as explicit `pmbus_lock_interruptible()`/`pmbus_unlock()` ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/hwmon/pmbus/adm1266.c | 40 +++++++++++++++++++++++++++++------
1 file changed, 34 insertions(+), 6 deletions(-)
diff --git a/drivers/hwmon/pmbus/adm1266.c b/drivers/hwmon/pmbus/adm1266.c
index a8690d6c9b9cb0..518eaf07a123de 100644
--- a/drivers/hwmon/pmbus/adm1266.c
+++ b/drivers/hwmon/pmbus/adm1266.c
@@ -173,7 +173,12 @@ static int adm1266_gpio_get(struct gpio_chip *chip, unsigned int offset)
else
pmbus_cmd = ADM1266_PDIO_STATUS;
+ ret = pmbus_lock_interruptible(data->client);
+ if (ret)
+ return ret;
+
ret = i2c_smbus_read_block_data(data->client, pmbus_cmd, read_buf);
+ pmbus_unlock(data->client);
if (ret < 0)
return ret;
if (ret < 2)
@@ -195,11 +200,19 @@ static int adm1266_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask
unsigned int gpio_nr;
int ret;
+ ret = pmbus_lock_interruptible(data->client);
+ if (ret)
+ return ret;
+
ret = i2c_smbus_read_block_data(data->client, ADM1266_GPIO_STATUS, read_buf);
- if (ret < 0)
+ if (ret < 0) {
+ pmbus_unlock(data->client);
return ret;
- if (ret < 2)
+ }
+ if (ret < 2) {
+ pmbus_unlock(data->client);
return -EIO;
+ }
status = read_buf[0] + (read_buf[1] << 8);
@@ -210,10 +223,14 @@ static int adm1266_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask
}
ret = i2c_smbus_read_block_data(data->client, ADM1266_PDIO_STATUS, read_buf);
- if (ret < 0)
+ if (ret < 0) {
+ pmbus_unlock(data->client);
return ret;
- if (ret < 2)
+ }
+ if (ret < 2) {
+ pmbus_unlock(data->client);
return -EIO;
+ }
status = read_buf[0] + (read_buf[1] << 8);
@@ -222,6 +239,8 @@ static int adm1266_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask
set_bit(gpio_nr, bits);
}
+ pmbus_unlock(data->client);
+
return 0;
}
@@ -236,11 +255,16 @@ static void adm1266_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
int ret;
int i;
+ if (pmbus_lock_interruptible(data->client))
+ return;
+
for (i = 0; i < ADM1266_GPIO_NR; i++) {
write_cmd = adm1266_gpio_mapping[i][1];
ret = adm1266_pmbus_block_xfer(data, ADM1266_GPIO_CONFIG, 1, &write_cmd, read_buf);
- if (ret != 2)
+ if (ret != 2) {
+ pmbus_unlock(data->client);
return;
+ }
gpio_config = read_buf[0];
seq_puts(s, adm1266_names[i]);
@@ -262,8 +286,10 @@ static void adm1266_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
write_cmd = 0xFF;
ret = adm1266_pmbus_block_xfer(data, ADM1266_PDIO_CONFIG, 1, &write_cmd, read_buf);
- if (ret != 32)
+ if (ret != 32) {
+ pmbus_unlock(data->client);
return;
+ }
for (i = 0; i < ADM1266_PDIO_NR; i++) {
seq_puts(s, adm1266_names[ADM1266_GPIO_NR + i]);
@@ -286,6 +312,8 @@ static void adm1266_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
seq_puts(s, ")\n");
}
+
+ pmbus_unlock(data->client);
}
static int adm1266_config_gpio(struct adm1266_data *data)
--
2.53.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 6.6.y] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with pmbus_lock
2026-06-02 2:06 ` Sasha Levin
@ 2026-06-04 0:05 ` Sasha Levin
0 siblings, 0 replies; 4+ messages in thread
From: Sasha Levin @ 2026-06-04 0:05 UTC (permalink / raw)
To: stable; +Cc: Sasha Levin, Abdurrahman Hussain, Bartosz Golaszewski,
Guenter Roeck
> [PATCH 6.6.y] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with
> pmbus_lock
> [ open-coded each guard(pmbus_lock)(data->client) as explicit
> pmbus_lock_interruptible()/pmbus_unlock() ]
Queued for 6.6.y and 6.1.y, thanks.
--
Thanks,
Sasha
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2026-06-04 0:05 UTC | newest]
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2026-05-28 13:39 FAILED: patch "[PATCH] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with" failed to apply to 6.6-stable tree gregkh
2026-06-01 20:28 ` [PATCH 6.6.y] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with pmbus_lock Sasha Levin
2026-06-02 2:06 ` Sasha Levin
2026-06-04 0:05 ` Sasha Levin
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