b6c9b15e44
Hot-plugging SAS wire of direct hard disk backplane may cause disk lost. We have done this test with several types of SATA disk from different venders, and only two models from Seagate has this problem, ST4000NM0035-1V4107 and ST3000VM002-1ET166. The root cause is that the disk doesn't send D2H frame after OOB finished. SAS controller will issue phyup interrupt only when D2H frame is received, otherwise, will be waiting there all the time. When this issue happen, we can find the disk again with link reset. To fix this issue, we setup an timer after OOB finished. If the PHY is not up in 20s, do link reset. Notes: the 20s is an experience value. Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.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.