FAILED: patch "[PATCH] hwmon: (tmp102) Fix jiffies wraparound in conversion-ready check" failed to apply to 6.12-stable tree

FAILED: patch "[PATCH] hwmon: (tmp102) Fix jiffies wraparound in conversion-ready check" failed to apply to 6.12-stable tree

[Sasha Levin]

The patch below does not apply to the 6.12-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-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 56c1d32323e773b8b927316f8beeae9238576335
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '20261107051756-failed-6.12-56c1d32323e7@kernel.org' --subject-prefix 'PATCH 6.12.y' 'HEAD^..'

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From 56c1d32323e773b8b927316f8beeae9238576335 Mon Sep 17 00:00:00 2001
From: Tom Verdonck <tom.verdonck@inspiral.be>
Date: Fri, 25 Sep 2026 20:23:22 +0200
Subject: [PATCH] hwmon: (tmp102) Fix jiffies wraparound in conversion-ready
 check

tmp102 records a one-shot deadline in ->ready_time at probe (and resume)
and, on every temperature read, refuses the read with -EAGAIN while
time_before(jiffies, ready_time) is true, in order to skip the first
~35 ms conversion.

->ready_time is an unsigned long compared with time_before(), whose
signed difference is only meaningful while the two values are within
LONG_MAX jiffies of each other. Because ->ready_time is set once and
never refreshed, jiffies keeps advancing away from it, and after 2^31
jiffies the difference flips sign. On a 32-bit HZ=100 kernel that
happens ~248.5 days after boot: time_before() then permanently reports
"not ready" and the driver returns -EAGAIN on every read, without ever
touching the sensor, until the next reboot.

Store the deadline as a 64-bit jiffies value and compare it with
get_jiffies_64()/time_before64(), which does not wrap in any practical
uptime.

Fixes: 3d8f7a89a197 ("hwmon: (tmp102) Improve handling of initial read delay")
Cc: stable@vger.kernel.org
Signed-off-by: Tom Verdonck <tom.verdonck@inspiral.be>
Link: https://patch.msgid.link/2952f070f82913aea96eec25d28008d3b9058656.1790358356.git.tom.verdonck@inspiral.be
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
 drivers/hwmon/tmp102.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/hwmon/tmp102.c b/drivers/hwmon/tmp102.c
index 50a8b050d8da1..8c8463ddb6c45 100644
--- a/drivers/hwmon/tmp102.c
+++ b/drivers/hwmon/tmp102.c
@@ -58,7 +58,7 @@ struct tmp102 {
 	const char *label;
 	struct regmap *regmap;
 	u16 config_orig;
-	unsigned long ready_time;
+	u64 ready_time;
 	u16 sample_time;
 };
 
@@ -106,7 +106,7 @@ static int tmp102_read_temp(struct device *dev, u32 attr, long *val)
 	switch (attr) {
 	case hwmon_temp_input:
 		/* Is it too early to return a conversion ? */
-		if (time_before(jiffies, tmp102->ready_time)) {
+		if (time_before64(get_jiffies_64(), tmp102->ready_time)) {
 			dev_dbg(dev, "%s: Conversion not ready yet..\n", __func__);
 			return -EAGAIN;
 		}
@@ -354,7 +354,7 @@ static int tmp102_probe(struct i2c_client *client)
 	 * Mark that we are not ready with data until the first
 	 * conversion is complete
 	 */
-	tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS);
+	tmp102->ready_time = get_jiffies_64() + msecs_to_jiffies(CONVERSION_TIME_MS);
 
 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
 							 tmp102,
@@ -387,7 +387,7 @@ static int tmp102_resume(struct device *dev)
 	err = regmap_update_bits(tmp102->regmap, TMP102_CONF_REG,
 				 TMP102_CONF_SD, 0);
 
-	tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS);
+	tmp102->ready_time = get_jiffies_64() + msecs_to_jiffies(CONVERSION_TIME_MS);
 
 	return err;
 }
-- 
2.53.0

[PATCH 6.12.y 1/3] kernel.h: move READ/WRITE definitions to <linux/types.h>

[Sasha Levin]

From: Ingo Molnar <mingo@kernel.org>

[ Upstream commit 4ef5211ee68113070bd42142f06347866675055e ]

Patch series "kernel.h: Move out a couple of macros and constants".

kernel.h hosts a couple of macros and constants that may be better placed.
Do that.  Also add missing documentation.  No functional changes
intended.

This patch (of 2):

Headers shouldn't be forced to include <linux/kernel.h> just to
gain these simple constants.

Link: https://lkml.kernel.org/r/20250324105228.775784-1-andriy.shevchenko@linux.intel.com
Link: https://lkml.kernel.org/r/20250324105228.775784-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Alexandru Ardelean <aardelean@baylibre.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Stable-dep-of: 56c1d32323e7 ("hwmon: (tmp102) Fix jiffies wraparound in conversion-ready check")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/linux/kernel.h | 4 ----
 include/linux/types.h  | 4 ++++
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index be2e8c0a187e4..01bb0fac36672 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -41,10 +41,6 @@
 
 #define STACK_MAGIC	0xdeadbeef
 
-/* generic data direction definitions */
-#define READ			0
-#define WRITE			1
-
 #define PTR_IF(cond, ptr)	((cond) ? (ptr) : NULL)
 
 #define u64_to_user_ptr(x) (		\
diff --git a/include/linux/types.h b/include/linux/types.h
index f1356a9a5730a..5e997dd8b4bbc 100644
--- a/include/linux/types.h
+++ b/include/linux/types.h
@@ -135,6 +135,10 @@ typedef s64	ktime_t;
 typedef u64 sector_t;
 typedef u64 blkcnt_t;
 
+/* generic data direction definitions */
+#define READ			0
+#define WRITE			1
+
 /*
  * The type of an index into the pagecache.
  */
-- 
2.53.0

[PATCH 6.12.y 2/3] kernel.h: move PTR_IF() and u64_to_user_ptr() to util_macros.h

[Sasha Levin]

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

[ Upstream commit 029c896c4105b7d74fcd88d99c5fbab2558fee89 ]

While the natural choice of PTR_IF() is kconfig.h, the latter is too broad
to include C code and actually the macro was moved out from there in the
past.  But kernel.h is neither a good choice for that.  Move it to
util_macros.h.  Do the same for u64_to_user_ptr().

While moving, add necessary documentation.

Link: https://lkml.kernel.org/r/20250324105228.775784-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Alexandru Ardelean <aardelean@baylibre.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Stable-dep-of: 56c1d32323e7 ("hwmon: (tmp102) Fix jiffies wraparound in conversion-ready check")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/linux/kernel.h      | 10 +-----
 include/linux/util_macros.h | 66 +++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+), 9 deletions(-)

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 01bb0fac36672..1cce1f6410a9d 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -33,6 +33,7 @@
 #include <linux/sprintf.h>
 #include <linux/static_call_types.h>
 #include <linux/instruction_pointer.h>
+#include <linux/util_macros.h>
 #include <linux/wordpart.h>
 
 #include <asm/byteorder.h>
@@ -41,15 +42,6 @@
 
 #define STACK_MAGIC	0xdeadbeef
 
-#define PTR_IF(cond, ptr)	((cond) ? (ptr) : NULL)
-
-#define u64_to_user_ptr(x) (		\
-{					\
-	typecheck(u64, (x));		\
-	(void __user *)(uintptr_t)(x);	\
-}					\
-)
-
 struct completion;
 struct user;
 
diff --git a/include/linux/util_macros.h b/include/linux/util_macros.h
index 825487fb66faf..785a970323bbc 100644
--- a/include/linux/util_macros.h
+++ b/include/linux/util_macros.h
@@ -64,6 +64,72 @@
 	(__fc_i);							\
 })
 
+/**
+ * PTR_IF - evaluate to @ptr if @cond is true, or to NULL otherwise.
+ * @cond: A conditional, usually in a form of IS_ENABLED(CONFIG_FOO)
+ * @ptr: A pointer to assign if @cond is true.
+ *
+ * PTR_IF(IS_ENABLED(CONFIG_FOO), ptr) evaluates to @ptr if CONFIG_FOO is set
+ * to 'y' or 'm', or to NULL otherwise. The (ptr) argument must be a pointer.
+ *
+ * The macro can be very useful to help compiler dropping dead code.
+ *
+ * For instance, consider the following::
+ *
+ *     #ifdef CONFIG_FOO_SUSPEND
+ *     static int foo_suspend(struct device *dev)
+ *     {
+ *        ...
+ *     }
+ *     #endif
+ *
+ *     static struct pm_ops foo_ops = {
+ *     #ifdef CONFIG_FOO_SUSPEND
+ *         .suspend = foo_suspend,
+ *     #endif
+ *     };
+ *
+ * While this works, the foo_suspend() macro is compiled conditionally,
+ * only when CONFIG_FOO_SUSPEND is set. This is problematic, as there could
+ * be a build bug in this function, we wouldn't have a way to know unless
+ * the configuration option is set.
+ *
+ * An alternative is to declare foo_suspend() always, but mark it
+ * as __maybe_unused. This works, but the __maybe_unused attribute
+ * is required to instruct the compiler that the function may not
+ * be referenced anywhere, and is safe to remove without making
+ * a fuss about it. This makes the programmer responsible for tagging
+ * the functions that can be garbage-collected.
+ *
+ * With the macro it is possible to write the following:
+ *
+ *     static int foo_suspend(struct device *dev)
+ *     {
+ *        ...
+ *     }
+ *
+ *     static struct pm_ops foo_ops = {
+ *         .suspend = PTR_IF(IS_ENABLED(CONFIG_FOO_SUSPEND), foo_suspend),
+ *     };
+ *
+ * The foo_suspend() function will now be automatically dropped by the
+ * compiler, and it does not require any specific attribute.
+ */
+#define PTR_IF(cond, ptr)	((cond) ? (ptr) : NULL)
+
+/**
+ * to_user_ptr - cast a pointer passed as u64 from user space to void __user *
+ * @x: The u64 value from user space, usually via IOCTL
+ *
+ * to_user_ptr() simply casts a pointer passed as u64 from user space to void
+ * __user * correctly. Using this lets us get rid of all the tiresome casts.
+ */
+#define u64_to_user_ptr(x)		\
+({					\
+	typecheck(u64, (x));		\
+	(void __user *)(uintptr_t)(x);	\
+})
+
 /**
  * is_insidevar - check if the @ptr points inside the @var memory range.
  * @ptr:	the pointer to a memory address.
-- 
2.53.0

[PATCH 6.12.y 3/3] hwmon: (tmp102) Fix jiffies wraparound in conversion-ready check

[Sasha Levin]

From: Tom Verdonck <tom.verdonck@inspiral.be>

[ Upstream commit 56c1d32323e773b8b927316f8beeae9238576335 ]

tmp102 records a one-shot deadline in ->ready_time at probe (and resume)
and, on every temperature read, refuses the read with -EAGAIN while
time_before(jiffies, ready_time) is true, in order to skip the first
~35 ms conversion.

->ready_time is an unsigned long compared with time_before(), whose
signed difference is only meaningful while the two values are within
LONG_MAX jiffies of each other. Because ->ready_time is set once and
never refreshed, jiffies keeps advancing away from it, and after 2^31
jiffies the difference flips sign. On a 32-bit HZ=100 kernel that
happens ~248.5 days after boot: time_before() then permanently reports
"not ready" and the driver returns -EAGAIN on every read, without ever
touching the sensor, until the next reboot.

Store the deadline as a 64-bit jiffies value and compare it with
get_jiffies_64()/time_before64(), which does not wrap in any practical
uptime.

Fixes: 3d8f7a89a197 ("hwmon: (tmp102) Improve handling of initial read delay")
Cc: stable@vger.kernel.org
Signed-off-by: Tom Verdonck <tom.verdonck@inspiral.be>
Link: https://patch.msgid.link/2952f070f82913aea96eec25d28008d3b9058656.1790358356.git.tom.verdonck@inspiral.be
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
[ sashal: adjusted context because the conversion-ready check is in tmp102_read() rather than tmp102_read_temp() ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/hwmon/tmp102.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/hwmon/tmp102.c b/drivers/hwmon/tmp102.c
index 8af44a33055f3..967d2e7e8ccf3 100644
--- a/drivers/hwmon/tmp102.c
+++ b/drivers/hwmon/tmp102.c
@@ -54,7 +54,7 @@
 struct tmp102 {
 	struct regmap *regmap;
 	u16 config_orig;
-	unsigned long ready_time;
+	u64 ready_time;
 };
 
 /* convert left adjusted 13-bit TMP102 register value to milliCelsius */
@@ -79,7 +79,7 @@ static int tmp102_read(struct device *dev, enum hwmon_sensor_types type,
 	switch (attr) {
 	case hwmon_temp_input:
 		/* Is it too early to return a conversion ? */
-		if (time_before(jiffies, tmp102->ready_time)) {
+		if (time_before64(get_jiffies_64(), tmp102->ready_time)) {
 			dev_dbg(dev, "%s: Conversion not ready yet..\n", __func__);
 			return -EAGAIN;
 		}
@@ -245,7 +245,7 @@ static int tmp102_probe(struct i2c_client *client)
 	 * Mark that we are not ready with data until the first
 	 * conversion is complete
 	 */
-	tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS);
+	tmp102->ready_time = get_jiffies_64() + msecs_to_jiffies(CONVERSION_TIME_MS);
 
 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
 							 tmp102,
@@ -278,7 +278,7 @@ static int tmp102_resume(struct device *dev)
 	err = regmap_update_bits(tmp102->regmap, TMP102_CONF_REG,
 				 TMP102_CONF_SD, 0);
 
-	tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS);
+	tmp102->ready_time = get_jiffies_64() + msecs_to_jiffies(CONVERSION_TIME_MS);
 
 	return err;
 }
-- 
2.53.0