e8a10089ed
[ Upstream commit 712a1fcb38dc7cac6da63ee79a88708fbf9c45ec ]
The removal of the last MAX3100 device triggers the removal of
the driver. However, code doesn't update the respective global
variable and after insmod — rmmod — insmod cycle the kernel
oopses:
max3100 spi-PRP0001:01: max3100_probe: adding port 0
BUG: kernel NULL pointer dereference, address: 0000000000000408
...
RIP: 0010:serial_core_register_port+0xa0/0x840
...
max3100_probe+0x1b6/0x280 [max3100]
spi_probe+0x8d/0xb0
Update the actual state so next time UART driver will be registered
again.
Hugo also noticed, that the error path in the probe also affected
by having the variable set, and not cleared. Instead of clearing it
move the assignment after the successfull uart_register_driver() call.
Fixes: 7831d56b0a35 ("tty: MAX3100")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20240402195306.269276-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.