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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /Documentation/scsi/lpfc.rst
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+.. SPDX-License-Identifier: GPL-2.0
+
+=========================
+LPFC Driver Release Notes
+=========================
+
+
+.. important::
+
+ Starting in the 8.0.17 release, the driver began to be targeted strictly
+ toward the upstream kernel. As such, we removed #ifdefs for older kernels
+ (pre 2.6.10). The 8.0.16 release should be used if the driver is to be
+ run on one of the older kernels.
+
+ The proposed modifications to the transport layer for FC remote ports
+ and extended attribute support is now part of the upstream kernel
+ as of 2.6.12. We no longer need to provide patches for this support,
+ nor a *full* version which has old an new kernel support.
+
+ The driver now requires a 2.6.12 (if pre-release, 2.6.12-rc1) or later
+ kernel.
+
+ Please heed these dependencies....
+
+
+The following information is provided for additional background on the
+history of the driver as we push for upstream acceptance.
+
+Cable pull and temporary device Loss:
+
+ In older revisions of the lpfc driver, the driver internally queued i/o
+ received from the midlayer. In the cases where a cable was pulled, link
+ jitter, or a device temporarily loses connectivity (due to its cable
+ being removed, a switch rebooting, or a device reboot), the driver could
+ hide the disappearance of the device from the midlayer. I/O's issued to
+ the LLDD would simply be queued for a short duration, allowing the device
+ to reappear or link come back alive, with no inadvertent side effects
+ to the system. If the driver did not hide these conditions, i/o would be
+ errored by the driver, the mid-layer would exhaust its retries, and the
+ device would be taken offline. Manual intervention would be required to
+ re-enable the device.
+
+ The community supporting kernel.org has driven an effort to remove
+ internal queuing from all LLDDs. The philosophy is that internal
+ queuing is unnecessary as the block layer already performs the
+ queuing. Removing the queues from the LLDD makes a more predictable
+ and more simple LLDD.
+
+ As a potential new addition to kernel.org, the 8.x driver was asked to
+ have all internal queuing removed. Emulex complied with this request.
+ In explaining the impacts of this change, Emulex has worked with the
+ community in modifying the behavior of the SCSI midlayer so that SCSI
+ devices can be temporarily suspended while transport events (such as
+ those described) can occur.
+
+ The proposed patch was posted to the linux-scsi mailing list. The patch
+ is contained in the 2.6.10-rc2 (and later) patch kits. As such, this
+ patch is part of the standard 2.6.10 kernel.
+
+ By default, the driver expects the patches for block/unblock interfaces
+ to be present in the kernel. No #define needs to be set to enable support.
+
+
+Kernel Support
+==============
+
+ This source package is targeted for the upstream kernel only. (See notes
+ at the top of this file). It relies on interfaces that are slowing
+ migrating into the kernel.org kernel.
+
+ At this time, the driver requires the 2.6.12 (if pre-release, 2.6.12-rc1)
+ kernel.
+
+ If a driver is needed for older kernels please utilize the 8.0.16
+ driver sources.
+
+
+Patches
+=======
+
+ Thankfully, at this time, patches are not needed.