cce5dc0333
This reverts commit 24cd0b9bfdff126c066032b0d40ab0962d35e777.
1) commit 4e89dce72521 ("iommu/iova: Retry from last rb tree node if
iova search fails") tries to fix that iova allocation can fail while
there are still free space available. This is not backported to 5.10
stable.
2) commit fce54ed02757 ("scsi: hisi_sas: Limit max hw sectors for v3
HW") fix the performance regression introduced by 1), however, this
is just a temporary solution and will cause io performance regression
because it limit max io size to PAGE_SIZE * 32(128k for 4k page_size).
3) John Garry posted a patchset to fix the problem.
4) The temporary solution is reverted.
It's weird that the patch in 2) is backported to 5.10 stable alone,
while the right thing to do is to backport them all together.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.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.