6f14228e82
commit e65851989001c0c9ba9177564b13b38201c0854c upstream.
Storage devices are free to send RSCNs, e.g. for internal state changes. If
this happens on all connected paths, zfcp risks temporarily losing all
paths at the same time. This has strong requirements on multipath
configuration such as "no_path_retry queue".
Avoid such situations by deferring fc_rport blocking until after the ADISC
response, when any actual state change of the remote port became clear.
The already existing port recovery triggers explicitly block the fc_rport.
The triggers are: on ADISC reject or timeout (typical cable pull case), and
on ADISC indicating that the remote port has changed its WWPN or
the port is meanwhile no longer open.
As a side effect, this also removes a confusing direct function call to
another work item function zfcp_scsi_rport_work() instead of scheduling
that other work item. It was probably done that way to have the rport block
side effect immediate and synchronous to the caller.
Fixes: a2fa0aede07c ("[SCSI] zfcp: Block FC transport rports early on errors")
Cc: stable@vger.kernel.org #v2.6.30+
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Fedor Loshakov <loshakov@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Link: https://lore.kernel.org/r/20230724145156.3920244-1-maier@linux.ibm.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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.