[PATCH 0/7] i2c: provide and use i2c_adapter_set_node()

[PATCH 0/7] i2c: provide and use i2c_adapter_set_node()

[Bartosz Golaszewski]

It's been another year of discussing the object life-time problems at
conferences. I2C is one of the offenders and its problems are more
complex than those of some other subsystems. It seems the revocable[1]
API may make its way into the kernel this year but even with it in
place, I2C won't be able to use it as there's currently nothing to
*revoke*. The struct device is embedded within the i2c_adapter struct
whose lifetime is tied to the provider device being bound to its driver.

Fixing this won't be fast and easy but nothing's going to happen if we
don't start chipping away at it. The ultimate goal in order to be able
to use an SRCU-based solution (revocable or otherwise) is to convert the
embedded struct device in struct i2c_adapter into an __rcu pointer that
can be *revoked*. To that end we need to hide all dereferences of
adap->dev in drivers.

I2C drivers use device_set_node() to assign a firmware node directly to
the struct device embedded in i2c_adapter. In order to hide the direct
dereferencing: provide a dedicated interface that wraps the call to
device_set_node() but takes the adapter as argument instead.

[1] https://lore.kernel.org/all/20251106152330.11733-1-tzungbi@kernel.org/

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
Bartosz Golaszewski (7):
      i2c: provide i2c_adapter_set_node()
      i2c: designware-common: use i2c_adapter_set_node()
      i2c: gpio: use i2c_adapter_set_node()
      i2c: ljca: use i2c_adapter_set_node()
      i2c: ls2x: use i2c_adapter_set_node()
      i2c: rzv2m: use i2c_adapter_set_node()
      i2c: usbio: use i2c_adapter_set_node()

 drivers/i2c/busses/i2c-designware-common.c | 2 +-
 drivers/i2c/busses/i2c-gpio.c              | 2 +-
 drivers/i2c/busses/i2c-ljca.c              | 2 +-
 drivers/i2c/busses/i2c-ls2x.c              | 2 +-
 drivers/i2c/busses/i2c-rzv2m.c             | 2 +-
 drivers/i2c/busses/i2c-usbio.c             | 2 +-
 include/linux/i2c.h                        | 7 +++++++
 7 files changed, 13 insertions(+), 6 deletions(-)
---
base-commit: 9448598b22c50c8a5bb77a9103e2d49f134c9578
change-id: 20251223-i2c-ada-dev-set-node-0636a8d3666c

Best regards,
-- 
Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

[PATCH 1/7] i2c: provide i2c_adapter_set_node()

[Bartosz Golaszewski]

Provide a wrapper around device_set_node() that takes the i2c_adapter as
argument. This allows us to hide more dereferencing of the embedded
struct device as part of working towards fixing the object lifetime
issues in i2c.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
 include/linux/i2c.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 20fd41b51d5c85ee1665395c07345faafd8e2fca..38448bdfac671adcdf341adbe2f52341e5aec41a 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -29,6 +29,7 @@ extern const struct device_type i2c_client_type;
 
 /* --- General options ------------------------------------------------	*/
 
+struct fwnode_handle;
 struct i2c_msg;
 struct i2c_adapter;
 struct i2c_client;
@@ -778,6 +779,12 @@ static inline void i2c_set_adapdata(struct i2c_adapter *adap, void *data)
 	dev_set_drvdata(&adap->dev, data);
 }
 
+static inline void i2c_adapter_set_node(struct i2c_adapter *adap,
+					struct fwnode_handle *fwnode)
+{
+	device_set_node(&adap->dev, fwnode);
+}
+
 static inline struct i2c_adapter *
 i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
 {

-- 
2.47.3

[PATCH 2/7] i2c: designware-common: use i2c_adapter_set_node()

[Bartosz Golaszewski]

Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
This allows us to hide the dereferencing of the embedded struct device.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
 drivers/i2c/busses/i2c-designware-common.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
index 5b1e8f74c4acf4ca875beb1fdc736a89e4a357b9..c9644c927b4adf29dccf7e377bfed744844c5512 100644
--- a/drivers/i2c/busses/i2c-designware-common.c
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -743,7 +743,7 @@ EXPORT_SYMBOL_GPL(i2c_dw_disable);
 
 int i2c_dw_probe(struct dw_i2c_dev *dev)
 {
-	device_set_node(&dev->adapter.dev, dev_fwnode(dev->dev));
+	i2c_adapter_set_node(&dev->adapter, dev_fwnode(dev->dev));
 
 	switch (dev->mode) {
 	case DW_IC_SLAVE:

-- 
2.47.3

[PATCH 3/7] i2c: gpio: use i2c_adapter_set_node()

[Bartosz Golaszewski]

Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
This allows us to hide the dereferencing of the embedded struct device.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
 drivers/i2c/busses/i2c-gpio.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c
index f4355b17bfbf15c402e71096ccbb99f5a35bb479..4984736969e1bf2d11620772214cb13ceb411b6a 100644
--- a/drivers/i2c/busses/i2c-gpio.c
+++ b/drivers/i2c/busses/i2c-gpio.c
@@ -426,7 +426,7 @@ static int i2c_gpio_probe(struct platform_device *pdev)
 	adap->algo_data = bit_data;
 	adap->class = I2C_CLASS_HWMON;
 	adap->dev.parent = dev;
-	device_set_node(&adap->dev, fwnode);
+	i2c_adapter_set_node(adap, fwnode);
 
 	adap->nr = pdev->id;
 	ret = i2c_bit_add_numbered_bus(adap);

-- 
2.47.3

[PATCH 4/7] i2c: ljca: use i2c_adapter_set_node()

[Bartosz Golaszewski]

Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
This allows us to hide the dereferencing of the embedded struct device.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
 drivers/i2c/busses/i2c-ljca.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-ljca.c b/drivers/i2c/busses/i2c-ljca.c
index 93274f0c2d72166bf017f65af797f418743b6a57..fb45019b1a0c583f19bce3523983a79d632da3da 100644
--- a/drivers/i2c/busses/i2c-ljca.c
+++ b/drivers/i2c/busses/i2c-ljca.c
@@ -294,7 +294,7 @@ static int ljca_i2c_probe(struct auxiliary_device *auxdev,
 		 dev_name(&auxdev->dev), dev_name(auxdev->dev.parent),
 		 ljca_i2c->i2c_info->id);
 
-	device_set_node(&ljca_i2c->adap.dev, dev_fwnode(&auxdev->dev));
+	i2c_adapter_set_node(&ljca_i2c->adap, dev_fwnode(&auxdev->dev));
 
 	i2c_set_adapdata(&ljca_i2c->adap, ljca_i2c);
 	auxiliary_set_drvdata(auxdev, ljca_i2c);

-- 
2.47.3

[PATCH 5/7] i2c: ls2x: use i2c_adapter_set_node()

[Bartosz Golaszewski]

Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
This allows us to hide the dereferencing of the embedded struct device.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
 drivers/i2c/busses/i2c-ls2x.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-ls2x.c b/drivers/i2c/busses/i2c-ls2x.c
index b475dd27b7af94a22537f1000e95606774d6c7f2..217a55d7d90b2e515ef33e9014263958d9258b00 100644
--- a/drivers/i2c/busses/i2c-ls2x.c
+++ b/drivers/i2c/busses/i2c-ls2x.c
@@ -312,7 +312,7 @@ static int ls2x_i2c_probe(struct platform_device *pdev)
 	adap->owner = THIS_MODULE;
 	adap->algo = &ls2x_i2c_algo;
 	adap->timeout = msecs_to_jiffies(100);
-	device_set_node(&adap->dev, dev_fwnode(dev));
+	i2c_adapter_set_node(adap, dev_fwnode(dev));
 	i2c_set_adapdata(adap, priv);
 	strscpy(adap->name, pdev->name, sizeof(adap->name));
 	init_completion(&priv->cmd_complete);

-- 
2.47.3

[PATCH 6/7] i2c: rzv2m: use i2c_adapter_set_node()

[Bartosz Golaszewski]

Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
This allows us to hide the dereferencing of the embedded struct device.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
 drivers/i2c/busses/i2c-rzv2m.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-rzv2m.c b/drivers/i2c/busses/i2c-rzv2m.c
index 2387148506736a65378809971bfbddfb436b6c4d..f31d5b90802477a3d27557a4a92ca2b26023e343 100644
--- a/drivers/i2c/busses/i2c-rzv2m.c
+++ b/drivers/i2c/busses/i2c-rzv2m.c
@@ -451,7 +451,7 @@ static int rzv2m_i2c_probe(struct platform_device *pdev)
 	adap->quirks = &rzv2m_i2c_quirks;
 	adap->dev.parent = dev;
 	adap->owner = THIS_MODULE;
-	device_set_node(&adap->dev, dev_fwnode(dev));
+	i2c_adapter_set_node(adap, dev_fwnode(dev));
 	i2c_set_adapdata(adap, priv);
 	strscpy(adap->name, pdev->name, sizeof(adap->name));
 	init_completion(&priv->msg_tia_done);

-- 
2.47.3

[PATCH 7/7] i2c: usbio: use i2c_adapter_set_node()

[Bartosz Golaszewski]

Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
This allows us to hide the dereferencing of the embedded struct device.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
 drivers/i2c/busses/i2c-usbio.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-usbio.c b/drivers/i2c/busses/i2c-usbio.c
index e7799abf67877906c7787235bddb28ac23168077..4824d61fc85d7b23fd7f6a8c2be5809ad9fe2613 100644
--- a/drivers/i2c/busses/i2c-usbio.c
+++ b/drivers/i2c/busses/i2c-usbio.c
@@ -278,7 +278,7 @@ static int usbio_i2c_probe(struct auxiliary_device *adev,
 	snprintf(i2c->adap.name, sizeof(i2c->adap.name), "%s.%d",
 		 USBIO_I2C_CLIENT, i2c->adev->id);
 
-	device_set_node(&i2c->adap.dev, dev_fwnode(&adev->dev));
+	i2c_adapter_set_node(&i2c->adap, dev_fwnode(&adev->dev));
 
 	auxiliary_set_drvdata(adev, i2c);
 	i2c_set_adapdata(&i2c->adap, i2c);

-- 
2.47.3

Re: [PATCH 0/7] i2c: provide and use i2c_adapter_set_node()

[Andy Shevchenko]

On Tue, Dec 23, 2025 at 11:06:47AM +0100, Bartosz Golaszewski wrote:
> It's been another year of discussing the object life-time problems at
> conferences. I2C is one of the offenders and its problems are more
> complex than those of some other subsystems. It seems the revocable[1]
> API may make its way into the kernel this year but even with it in
> place, I2C won't be able to use it as there's currently nothing to
> *revoke*. The struct device is embedded within the i2c_adapter struct
> whose lifetime is tied to the provider device being bound to its driver.
> 
> Fixing this won't be fast and easy but nothing's going to happen if we
> don't start chipping away at it. The ultimate goal in order to be able
> to use an SRCU-based solution (revocable or otherwise) is to convert the
> embedded struct device in struct i2c_adapter into an __rcu pointer that
> can be *revoked*. To that end we need to hide all dereferences of
> adap->dev in drivers.
> 
> I2C drivers use device_set_node() to assign a firmware node directly to
> the struct device embedded in i2c_adapter. In order to hide the direct
> dereferencing: provide a dedicated interface that wraps the call to
> device_set_node() but takes the adapter as argument instead.

> [1] https://lore.kernel.org/all/20251106152330.11733-1-tzungbi@kernel.org/

Can be also made as a Link tag and some people use `b4 shazam`, that uses the
above test as a merge commit message where other tags are also being
recognized.

Have no objection and code looks good,
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

-- 
With Best Regards,
Andy Shevchenko

RE: [PATCH 4/7] i2c: ljca: use i2c_adapter_set_node()

[Zhang, Lixu]

>-----Original Message-----
>From: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
>Sent: Tuesday, December 23, 2025 6:07 PM
>To: Wolfram Sang <wsa+renesas@sang-engineering.com>; Mika Westerberg
><mika.westerberg@linux.intel.com>; Andy Shevchenko
><andriy.shevchenko@linux.intel.com>; Jan Dabros <jsd@semihalf.com>; Andi
>Shyti <andi.shyti@kernel.org>; Zhang, Lixu <lixu.zhang@intel.com>; Sakari
>Ailus <sakari.ailus@linux.intel.com>; Binbin Zhou <zhoubinbin@loongson.cn>;
>Fabrizio Castro <fabrizio.castro.jz@renesas.com>; Cepeda Lopez, Israel A
><israel.a.cepeda.lopez@intel.com>; Hans de Goede <hansg@kernel.org>
>Cc: Bartosz Golaszewski <brgl@kernel.org>; linux-i2c@vger.kernel.org; linux-
>kernel@vger.kernel.org; linux-renesas-soc@vger.kernel.org; Bartosz
>Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
>Subject: [PATCH 4/7] i2c: ljca: use i2c_adapter_set_node()
>
>Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
>This allows us to hide the dereferencing of the embedded struct device.
>
>Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Reviewed-by: Zhang Lixu <lixu.zhang@intel.com>

Thanks,
Lixu

>---
> drivers/i2c/busses/i2c-ljca.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
>diff --git a/drivers/i2c/busses/i2c-ljca.c b/drivers/i2c/busses/i2c-ljca.c index
>93274f0c2d72166bf017f65af797f418743b6a57..fb45019b1a0c583f19bce3523
>983a79d632da3da 100644
>--- a/drivers/i2c/busses/i2c-ljca.c
>+++ b/drivers/i2c/busses/i2c-ljca.c
>@@ -294,7 +294,7 @@ static int ljca_i2c_probe(struct auxiliary_device
>*auxdev,
> 		 dev_name(&auxdev->dev), dev_name(auxdev->dev.parent),
> 		 ljca_i2c->i2c_info->id);
>
>-	device_set_node(&ljca_i2c->adap.dev, dev_fwnode(&auxdev->dev));
>+	i2c_adapter_set_node(&ljca_i2c->adap, dev_fwnode(&auxdev->dev));
>
> 	i2c_set_adapdata(&ljca_i2c->adap, ljca_i2c);
> 	auxiliary_set_drvdata(auxdev, ljca_i2c);
>
>--
>2.47.3

Re: [PATCH 4/7] i2c: ljca: use i2c_adapter_set_node()

[Sakari Ailus]

On Tue, Dec 23, 2025 at 11:06:51AM +0100, Bartosz Golaszewski wrote:
> Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
> This allows us to hide the dereferencing of the embedded struct device.
> 
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

-- 
Sakari Ailus

Re: [PATCH 7/7] i2c: usbio: use i2c_adapter_set_node()

[Sakari Ailus]

On Tue, Dec 23, 2025 at 11:06:54AM +0100, Bartosz Golaszewski wrote:
> Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
> This allows us to hide the dereferencing of the embedded struct device.
> 
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>

-- 
Sakari Ailus

Re: [PATCH 2/7] i2c: designware-common: use i2c_adapter_set_node()

[Mika Westerberg]

On Tue, Dec 23, 2025 at 11:06:49AM +0100, Bartosz Golaszewski wrote:
> Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
> This allows us to hide the dereferencing of the embedded struct device.
> 
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Re: [PATCH 5/7] i2c: ls2x: use i2c_adapter_set_node()

[Binbin Zhou]

On 2025/12/23 18:06, Bartosz Golaszewski wrote:
> Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
> This allows us to hide the dereferencing of the embedded struct device.
>
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Reviewed-by: Binbin Zhou <zhoubinbin@loongson.cn>

> ---
>   drivers/i2c/busses/i2c-ls2x.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/busses/i2c-ls2x.c b/drivers/i2c/busses/i2c-ls2x.c
> index b475dd27b7af94a22537f1000e95606774d6c7f2..217a55d7d90b2e515ef33e9014263958d9258b00 100644
> --- a/drivers/i2c/busses/i2c-ls2x.c
> +++ b/drivers/i2c/busses/i2c-ls2x.c
> @@ -312,7 +312,7 @@ static int ls2x_i2c_probe(struct platform_device *pdev)
>   	adap->owner = THIS_MODULE;
>   	adap->algo = &ls2x_i2c_algo;
>   	adap->timeout = msecs_to_jiffies(100);
> -	device_set_node(&adap->dev, dev_fwnode(dev));
> +	i2c_adapter_set_node(adap, dev_fwnode(dev));
>   	i2c_set_adapdata(adap, priv);
>   	strscpy(adap->name, pdev->name, sizeof(adap->name));
>   	init_completion(&priv->cmd_complete);
>

RE: [PATCH 6/7] i2c: rzv2m: use i2c_adapter_set_node()

[Fabrizio Castro]

> From: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
> Sent: 23 December 2025 10:07
> To: wsa+renesas <wsa+renesas@sang-engineering.com>; Mika Westerberg <mika.westerberg@linux.intel.com>;
> Andy Shevchenko <andriy.shevchenko@linux.intel.com>; Jan Dabros <jsd@semihalf.com>; Andi Shyti
> <andi.shyti@kernel.org>; Lixu Zhang <lixu.zhang@intel.com>; Sakari Ailus
> <sakari.ailus@linux.intel.com>; Binbin Zhou <zhoubinbin@loongson.cn>; Fabrizio Castro
> <fabrizio.castro.jz@renesas.com>; Israel Cepeda <israel.a.cepeda.lopez@intel.com>; Hans de Goede
> <hansg@kernel.org>
> Cc: Bartosz Golaszewski <brgl@kernel.org>; linux-i2c@vger.kernel.org; linux-kernel@vger.kernel.org;
> linux-renesas-soc@vger.kernel.org; Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
> Subject: [PATCH 6/7] i2c: rzv2m: use i2c_adapter_set_node()
> 
> Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
> This allows us to hide the dereferencing of the embedded struct device.
> 
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Reviewed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>

> ---
>  drivers/i2c/busses/i2c-rzv2m.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-rzv2m.c b/drivers/i2c/busses/i2c-rzv2m.c
> index 2387148506736a65378809971bfbddfb436b6c4d..f31d5b90802477a3d27557a4a92ca2b26023e343 100644
> --- a/drivers/i2c/busses/i2c-rzv2m.c
> +++ b/drivers/i2c/busses/i2c-rzv2m.c
> @@ -451,7 +451,7 @@ static int rzv2m_i2c_probe(struct platform_device *pdev)
>  	adap->quirks = &rzv2m_i2c_quirks;
>  	adap->dev.parent = dev;
>  	adap->owner = THIS_MODULE;
> -	device_set_node(&adap->dev, dev_fwnode(dev));
> +	i2c_adapter_set_node(adap, dev_fwnode(dev));
>  	i2c_set_adapdata(adap, priv);
>  	strscpy(adap->name, pdev->name, sizeof(adap->name));
>  	init_completion(&priv->msg_tia_done);
> 
> --
> 2.47.3

Re: [PATCH 3/7] i2c: gpio: use i2c_adapter_set_node()

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 467 bytes --]

On Tue, Dec 23, 2025 at 11:06:50AM +0100, Bartosz Golaszewski wrote:
> Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
> This allows us to hide the dereferencing of the embedded struct device.
> 
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Applying this patch fails for me. What is your base? I don't have the
commit referenced in the first patch series. I tried current top-of-tree
and current -next.


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Re: [PATCH 3/7] i2c: gpio: use i2c_adapter_set_node()

[Bartosz Golaszewski]

On Thu, 15 Jan 2026 19:28:51 +0100, Wolfram Sang
<wsa+renesas@sang-engineering.com> said:
> On Tue, Dec 23, 2025 at 11:06:50AM +0100, Bartosz Golaszewski wrote:
>> Use the dedicated wrapper for setting the fwnode of the i2c_adapter.
>> This allows us to hide the dereferencing of the embedded struct device.
>>
>> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
>
> Applying this patch fails for me. What is your base? I don't have the
> commit referenced in the first patch series. I tried current top-of-tree
> and current -next.
>

It's v6.19-rc2:

$ git show 9448598b22c50c8a5bb77a9103e2d49f134c9578
commit 9448598b22c50c8a5bb77a9103e2d49f134c9578 (tag: v6.19-rc2)
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Sun Dec 21 15:52:04 2025 -0800

    Linux 6.19-rc2

Bart