Re: [PATCH v1 1/1] serial: core: Restore sysfs fwnode information

From: Marek Szyprowski

Date: Thu Dec 18 2025 - 10:30:00 EST


On 27.11.2025 17:36, Andy Shevchenko wrote:
> The change that restores sysfs fwnode information does it only for OF cases.
> Update the fix to cover all possible types of fwnodes.
>
> Fixes: d36f0e9a0002 ("serial: core: restore of_node information in sysfs")
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---

This patch landed in today's linux-next as commit 24ec03cc5512 ("serial:
core: Restore sysfs fwnode information"). In my tests I found that it
breaks booting of most of my test boards (ARM 32 and 64 bit).
Unfortunately I cannot provide anything useful besides the information
that booting stops and system doesn't reach shell. There is nothing
suspicious in the kernel logs. I suspect a memory trashing. Reverting
$subject on top of linux-next fixes booting.

> drivers/tty/serial/serial_base_bus.c | 10 ++++++----
> 1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/tty/serial/serial_base_bus.c b/drivers/tty/serial/serial_base_bus.c
> index 22749ab0428a..8e891984cdc0 100644
> --- a/drivers/tty/serial/serial_base_bus.c
> +++ b/drivers/tty/serial/serial_base_bus.c
> @@ -13,7 +13,7 @@
> #include <linux/device.h>
> #include <linux/idr.h>
> #include <linux/module.h>
> -#include <linux/of.h>
> +#include <linux/property.h>
> #include <linux/serial_core.h>
> #include <linux/slab.h>
> #include <linux/spinlock.h>
> @@ -60,6 +60,7 @@ void serial_base_driver_unregister(struct device_driver *driver)
> driver_unregister(driver);
> }
>
> +/* On failure the caller must put device @dev with put_device() */
> static int serial_base_device_init(struct uart_port *port,
> struct device *dev,
> struct device *parent_dev,
> @@ -73,7 +74,8 @@ static int serial_base_device_init(struct uart_port *port,
> dev->parent = parent_dev;
> dev->bus = &serial_base_bus_type;
> dev->release = release;
> - device_set_of_node_from_dev(dev, parent_dev);
> +
> + device_set_node(dev, fwnode_handle_get(dev_fwnode(parent_dev)));
>
> if (!serial_base_initialized) {
> dev_dbg(port->dev, "uart_add_one_port() called before arch_initcall()?\n");
> @@ -94,7 +96,7 @@ static void serial_base_ctrl_release(struct device *dev)
> {
> struct serial_ctrl_device *ctrl_dev = to_serial_base_ctrl_device(dev);
>
> - of_node_put(dev->of_node);
> + fwnode_handle_put(dev_fwnode(dev));
> kfree(ctrl_dev);
> }
>
> @@ -142,7 +144,7 @@ static void serial_base_port_release(struct device *dev)
> {
> struct serial_port_device *port_dev = to_serial_base_port_device(dev);
>
> - of_node_put(dev->of_node);
> + fwnode_handle_put(dev_fwnode(dev));
> kfree(port_dev);
> }
>

Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland