2844e24343
cpsw_ethtool_begin directly returns the result of pm_runtime_get_sync
when successful.
pm_runtime_get_sync returns -error code on failure and 0 on successful
resume but also 1 when the device is already active. So the common case
for cpsw_ethtool_begin is to return 1. That leads to inconsistent calls
to pm_runtime_put in the call-chain so that pm_runtime_put is called
one too many times and as result leaving the cpsw dev behind suspended.
The suspended cpsw dev leads to an access violation later on by
different parts of the cpsw driver.
Fix this by calling the return-friendly pm_runtime_resume_and_get
function.
Fixes: d43c65b05b84 ("ethtool: runtime-resume netdev parent in ethnl_ops_begin")
Signed-off-by: Jan Sondhauss <jan.sondhauss@wago.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20220323084725.65864-1-jan.sondhauss@wago.com
Signed-off-by: Jakub Kicinski <kuba@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.