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Martin K. Petersen (Oracle) dc1b802f8e Merge patch series "libsas: rediscover improvements for linkrate/sas_addr"
Xingui Yang <yangxingui@huawei.com> says:

When a device attached to an expander phy experiences a linkrate change
(e.g., due to cable reconnection or negotiation), the current code in
sas_rediscover_dev() treats it as "broadcast flutter" and takes no action
if the SAS address and device type remain unchanged.

This series is based on John Garry's suggestion [1] to check the linkrate
and mark the device as gone and rediscover when flutter occurs, replacing
the previous v2 patch series that used lldd callbacks.

The previous v2 approach added lldd_dev_info_update callback which John
commented as "seem fragile and too specialized" [2]. This series adopts
a simpler approach that directly checks linkrate/sas_addr changes in
sas_rediscover_dev() and triggers rediscovery using libsas's standard
async discovery pattern.

This aligns with Jason Yan's earlier work [3] which was verified to
solve the linkrate change issue.

Additionally, per the discussion in v3 [4], the existing replace code
path also suffers from the same sysfs duplication issue:
sas_unregister_devs_sas_addr() only marks the device as gone, but the
actual sysfs cleanup happens later in sas_destruct_devices(). Calling
sas_discover_new() immediately after unregister causes sysfs_warn_dup()
errors. This series also optimizes the replace path to use the async
pattern, ensuring proper ordering for both flutter and replace cases.

[1] https://lore.kernel.org/linux-scsi/c4e4c99f-a13c-4e28-8650-48be1f96d7cf@oracle.com/
[2] https://lore.kernel.org/linux-scsi/28bd9d5b-f597-0aae-5340-bd951b2083aa@huawei.com/
[3] https://lore.kernel.org/linux-scsi/20190130082412.9357-6-yanaijie@huawei.com/
[4] https://lore.kernel.org/linux-scsi/b99cd59f-b986-432e-aaf1-3b757e1c4c34@oracle.com/
[5] https://lore.kernel.org/linux-scsi/11581a25-caa6-4ea3-9aa0-2a4dacb7f34e@oracle.com/
[6] https://lore.kernel.org/linux-scsi/20260624063230.3264029-1-yangxingui@huawei.com/

Link: https://patch.msgid.link/20260811040334.4184911-1-yangxingui@huawei.com
Signed-off-by: Martin K. Petersen (Oracle) <mkp@kernel.org>
2026-08-13 21:55:24 -04:00
arch LoongArch changes for v7.2 2026-06-26 08:42:49 -07:00
block block: handle REQ_OP_ZONE_APPEND in __bio_integrity_action 2026-06-24 06:53:25 -06:00
certs treewide: fix indentation and whitespace in Kconfig files 2026-05-28 21:24:42 -07:00
crypto mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -07:00
Documentation Merge patch series "scsi: Add LeapRAID driver support" 2026-08-07 11:59:18 -04:00
drivers Merge patch series "libsas: rediscover improvements for linkrate/sas_addr" 2026-08-13 21:55:24 -04:00
fs fscrypt fixes for 7.2 2026-06-27 09:20:16 -07:00
include Merge patch series "scsi: ufs: Add support for the aggregated read query opcode" 2026-08-07 11:34:35 -04:00
init mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -07:00
io_uring io_uring-7.2-20260625 2026-06-25 09:53:31 -07:00
ipc kernel-7.2-rc1.misc 2026-06-15 03:05:50 +05:30
kernel scsi: dma-mapping: Make dma_max_mapping_size() return 0 for no DMA capability 2026-07-26 18:09:43 -04:00
lib Misc fixes: 2026-06-23 16:05:54 -07:00
LICENSES LICENSES: Add modern form of the LGPL-2.1 tags to the usage guide section 2025-10-22 07:58:19 +02:00
mm block-7.2-20260625 2026-06-25 09:56:47 -07:00
net bpf-fixes 2026-06-25 14:09:26 -07:00
rust Rust changes for v7.2 (addendum) 2026-06-24 15:11:08 -07:00
samples Char/Misc/IIO/FPGA/GPIB/etc driver updates for 7.2-rc1 2026-06-22 12:20:21 -07:00
scripts Second round of Kbuild changes for 7.2 2026-06-25 09:06:12 -07:00
security * add Georgia Garcia as co-maintainer of apparmor 2026-06-24 12:33:40 -07:00
sound sound fixes for 7.2-rc1 2026-06-27 12:15:23 -07:00
tools LoongArch changes for v7.2 2026-06-26 08:42:49 -07:00
usr kbuild: uapi: also test UAPI headers against C++ compilers 2026-03-25 13:24:42 +01:00
virt s390: 2026-06-25 10:21:13 -07:00
.clang-format clang-format: fix formatting of guard() and scoped_guard() statements 2026-05-28 21:24:41 -07:00
.clippy.toml rust: bump Clippy's MSRV and clean incompatible_msrv allows 2026-04-07 09:51:39 +02:00
.cocciconfig
.editorconfig editorconfig: add rst extension 2026-01-26 19:07:09 -08:00
.get_maintainer.ignore .get_maintainer.ignore: add myself 2026-04-02 16:48:25 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore SPDX patches for 7.2-rc1 2026-06-22 12:06:22 -07:00
.mailmap Including fixes from netfilter and IPsec. 2026-06-25 12:25:36 -07:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -07:00
Kbuild checksyscalls: move instance functionality into generic code 2026-04-05 09:21:32 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS Merge patch series "scsi: Add LeapRAID driver support" 2026-08-07 11:59:18 -04:00
Makefile Linux 7.2-rc1 2026-06-28 12:01:31 -07:00
README docs: add AI Coding Assistants documentation 2026-01-06 14:55:06 -07:00

Linux kernel
============

The Linux kernel is the core of any Linux operating system. It manages hardware,
system resources, and provides the fundamental services for all other software.

Quick Start
-----------

* Report a bug: See Documentation/admin-guide/reporting-issues.rst
* Get the latest kernel: https://kernel.org
* Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst
* Join the community: https://lore.kernel.org/

Essential Documentation
-----------------------

All users should be familiar with:

* Building requirements: Documentation/process/changes.rst
* Code of Conduct: Documentation/process/code-of-conduct.rst
* License: See COPYING

Documentation can be built with make htmldocs or viewed online at:
https://www.kernel.org/doc/html/latest/


Who Are You?
============

Find your role below:

* New Kernel Developer - Getting started with kernel development
* Academic Researcher - Studying kernel internals and architecture
* Security Expert - Hardening and vulnerability analysis
* Backport/Maintenance Engineer - Maintaining stable kernels
* System Administrator - Configuring and troubleshooting
* Maintainer - Leading subsystems and reviewing patches
* Hardware Vendor - Writing drivers for new hardware
* Distribution Maintainer - Packaging kernels for distros
* AI Coding Assistant - LLMs and AI-powered development tools


For Specific Users
==================

New Kernel Developer
--------------------

Welcome! Start your kernel development journey here:

* Getting Started: Documentation/process/development-process.rst
* Your First Patch: Documentation/process/submitting-patches.rst
* Coding Style: Documentation/process/coding-style.rst
* Build System: Documentation/kbuild/index.rst
* Development Tools: Documentation/dev-tools/index.rst
* Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst
* Core APIs: Documentation/core-api/index.rst

Academic Researcher
-------------------

Explore the kernel's architecture and internals:

* Researcher Guidelines: Documentation/process/researcher-guidelines.rst
* Memory Management: Documentation/mm/index.rst
* Scheduler: Documentation/scheduler/index.rst
* Networking Stack: Documentation/networking/index.rst
* Filesystems: Documentation/filesystems/index.rst
* RCU (Read-Copy Update): Documentation/RCU/index.rst
* Locking Primitives: Documentation/locking/index.rst
* Power Management: Documentation/power/index.rst

Security Expert
---------------

Security documentation and hardening guides:

* Security Documentation: Documentation/security/index.rst
* LSM Development: Documentation/security/lsm-development.rst
* Self Protection: Documentation/security/self-protection.rst
* Reporting Vulnerabilities: Documentation/process/security-bugs.rst
* CVE Procedures: Documentation/process/cve.rst
* Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst
* Security Features: Documentation/userspace-api/seccomp_filter.rst

Backport/Maintenance Engineer
-----------------------------

Maintain and stabilize kernel versions:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* Backporting Guide: Documentation/process/backporting.rst
* Applying Patches: Documentation/process/applying-patches.rst
* Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git for Maintainers: Documentation/maintainer/configure-git.rst

System Administrator
--------------------

Configure, tune, and troubleshoot Linux systems:

* Admin Guide: Documentation/admin-guide/index.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst
* Tracing/Debugging: Documentation/trace/index.rst
* Performance Security: Documentation/admin-guide/perf-security.rst
* Hardware Monitoring: Documentation/hwmon/index.rst

Maintainer
----------

Lead kernel subsystems and manage contributions:

* Maintainer Handbook: Documentation/maintainer/index.rst
* Pull Requests: Documentation/maintainer/pull-requests.rst
* Managing Patches: Documentation/maintainer/modifying-patches.rst
* Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst
* Development Process: Documentation/process/maintainer-handbooks.rst
* Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git Configuration: Documentation/maintainer/configure-git.rst

Hardware Vendor
---------------

Write drivers and support new hardware:

* Driver API Guide: Documentation/driver-api/index.rst
* Driver Model: Documentation/driver-api/driver-model/driver.rst
* Device Drivers: Documentation/driver-api/infrastructure.rst
* Bus Types: Documentation/driver-api/driver-model/bus.rst
* Device Tree Bindings: Documentation/devicetree/bindings/
* Power Management: Documentation/driver-api/pm/index.rst
* DMA API: Documentation/core-api/dma-api.rst

Distribution Maintainer
-----------------------

Package and distribute the kernel:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* ABI Documentation: Documentation/ABI/README
* Kernel Configuration: Documentation/kbuild/kconfig.rst
* Module Signing: Documentation/admin-guide/module-signing.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst

AI Coding Assistant
-------------------

CRITICAL: If you are an LLM or AI-powered coding assistant, you MUST read and
follow the AI coding assistants documentation before contributing to the Linux
kernel:

* Documentation/process/coding-assistants.rst

This documentation contains essential requirements about licensing, attribution,
and the Developer Certificate of Origin that all AI tools must comply with.


Communication and Support
=========================

* Mailing Lists: https://lore.kernel.org/
* IRC: #kernelnewbies on irc.oftc.net
* Bugzilla: https://bugzilla.kernel.org/
* MAINTAINERS file: Lists subsystem maintainers and mailing lists
* Email Clients: Documentation/process/email-clients.rst