49da96d779
Offlining a SATA device connected to a hisi SAS controller and then scanning the host will result in detecting 255 non-existent devices: # lsscsi [2:0:0:0] disk ATA Samsung SSD 860 2B6Q /dev/sda [2:0:1:0] disk ATA WDC WD2003FYYS-3 1D01 /dev/sdb [2:0:2:0] disk SEAGATE ST600MM0006 B001 /dev/sdc # echo "offline" > /sys/block/sdb/device/state # echo "- - -" > /sys/class/scsi_host/host2/scan # lsscsi [2:0:0:0] disk ATA Samsung SSD 860 2B6Q /dev/sda [2:0:1:0] disk ATA WDC WD2003FYYS-3 1D01 /dev/sdb [2:0:1:1] disk ATA WDC WD2003FYYS-3 1D01 /dev/sdh ... [2:0:1:255] disk ATA WDC WD2003FYYS-3 1D01 /dev/sdjb After a REPORT LUN command issued to the offline device fails, the SCSI midlayer tries to do a sequential scan of all devices whose LUN number is not 0. However, SATA does not support LUN numbers at all. Introduce a generic sas_slave_alloc() handler which will return -ENXIO for SATA devices if the requested LUN number is larger than 0 and make libsas drivers use this function as their .slave_alloc callback. Link: https://lore.kernel.org/r/20210622034037.1467088-1-yuyufen@huawei.com Reported-by: Wu Bo <wubo40@huawei.com> Suggested-by: John Garry <john.garry@huawei.com> Reviewed-by: John Garry <john.garry@huawei.com> Reviewed-by: Jason Yan <yanaijie@huawei.com> Signed-off-by: Yufen Yu <yuyufen@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.