42a87d4103
Until now there is no way to reset a AP queue or card. Driving a card or queue offline and online again does only toggle the 'software' online state. The only way to trigger a (hardware) reset is by running hot-unplug/hot-plug for example on the HMC. This patch makes the queue reset attribute in sysfs writable. Writing into this attribute triggers a reset on the AP queue's state machine. So the AP queue is flushed and state machine runs through the initial states which cause a reset (PQAP(RAPQ)) and a re-registration to interrupts (PQAP(AQIC)) if available. The reset sysfs attribute is writable by root only. So only an administrator is allowed to initiate a reset of AP queues. Please note that the queue's counter values are left untouched by the reset. Signed-off-by: Harald Freudenberger <freude@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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.