e52019c095
[ Upstream commit c45b2835e7b205783bdfe08cc98fa86a7c5eeb74 ]
child_fwnode should be a read only property based on the DT or ACPI. If
it's cleared on the parent device when a child is unloaded, then when
the child is loaded again the connection won't be remade.
child_dev should be cleared instead which signifies that the connection
should be remade when the child_fwnode registers a new coresight_device.
Similarly the reference count shouldn't be decremented as long as the
parent device exists. The correct place to drop the reference is in
coresight_release_platform_data() which is already done.
Reproducible on Juno with the following steps:
# load all coresight modules.
$ cd /sys/bus/coresight/devices/
$ echo 1 > tmc_etr0/enable_sink
$ echo 1 > etm0/enable_source
# Works fine ^
$ echo 0 > etm0/enable_source
$ rmmod coresight-funnel
$ modprobe coresight-funnel
$ echo 1 > etm0/enable_source
-bash: echo: write error: Invalid argument
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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.