bb278b149d
Consider this example where -> means LHS device is a consumer of RHS device and indentation represents "child of" of the previous device. Device A -> Device C Device B -> Device A Device C Without this commit: 1. Device A is added. 2. Device A is added to waiting for supplier list (Device C) 3. Device B is added 4. Device B is linked as a consumer to Device A 5. Device A doesn't probe because it's waiting for Device C to be added. 6. Device B doesn't probe because Device A hasn't probed. 7. Device C will never be added because it's parent hasn't probed. So, Device A, B and C will be in a probe/add deadlock. This commit detects this scenario and stops trying to create a device link between Device A and Device C since doing so would create the following cycle: Device A -> Devic C -(parent)-> Device B -> Device A. With this commit: 1. Device A is added. 3. Device B is added 4. Device B is linked as a consumer to Device A 5. Device A probes. 6. Device B probes because Device A has probed. 7. Device C is added and probed. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20200610011934.49795-3-saravanak@google.com Signed-off-by: Rob Herring <robh@kernel.org> |
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| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| 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 | ||
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.