Linus Torvalds 7fe6ac157b Merge tag 'for-7.1/block-20260411' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block updates from Jens Axboe:

 - Add shared memory zero-copy I/O support for ublk, bypassing per-I/O
   copies between kernel and userspace by matching registered buffer
   PFNs at I/O time. Includes selftests.

 - Refactor bio integrity to support filesystem initiated integrity
   operations and arbitrary buffer alignment.

 - Clean up bio allocation, splitting bio_alloc_bioset() into clear fast
   and slow paths. Add bio_await() and bio_submit_or_kill() helpers,
   unify synchronous bi_end_io callbacks.

 - Fix zone write plug refcount handling and plug removal races. Add
   support for serializing zone writes at QD=1 for rotational zoned
   devices, yielding significant throughput improvements.

 - Add SED-OPAL ioctls for Single User Mode management and a STACK_RESET
   command.

 - Add io_uring passthrough (uring_cmd) support to the BSG layer.

 - Replace pp_buf in partition scanning with struct seq_buf.

 - zloop improvements and cleanups.

 - drbd genl cleanup, switching to pre_doit/post_doit.

 - NVMe pull request via Keith:
      - Fabrics authentication updates
      - Enhanced block queue limits support
      - Workqueue usage updates
      - A new write zeroes device quirk
      - Tagset cleanup fix for loop device

 - MD pull requests via Yu Kuai:
      - Fix raid5 soft lockup in retry_aligned_read()
      - Fix raid10 deadlock with check operation and nowait requests
      - Fix raid1 overlapping writes on writemostly disks
      - Fix sysfs deadlock on array_state=clear
      - Proactive RAID-5 parity building with llbitmap, with
        write_zeroes_unmap optimization for initial sync
      - Fix llbitmap barrier ordering, rdev skipping, and bitmap_ops
        version mismatch fallback
      - Fix bcache use-after-free and uninitialized closure
      - Validate raid5 journal metadata payload size
      - Various cleanups

 - Various other fixes, improvements, and cleanups

* tag 'for-7.1/block-20260411' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (146 commits)
  ublk: fix tautological comparison warning in ublk_ctrl_reg_buf
  scsi: bsg: fix buffer overflow in scsi_bsg_uring_cmd()
  block: refactor blkdev_zone_mgmt_ioctl
  MAINTAINERS: update ublk driver maintainer email
  Documentation: ublk: address review comments for SHMEM_ZC docs
  ublk: allow buffer registration before device is started
  ublk: replace xarray with IDA for shmem buffer index allocation
  ublk: simplify PFN range loop in __ublk_ctrl_reg_buf
  ublk: verify all pages in multi-page bvec fall within registered range
  ublk: widen ublk_shmem_buf_reg.len to __u64 for 4GB buffer support
  xfs: use bio_await in xfs_zone_gc_reset_sync
  block: add a bio_submit_or_kill helper
  block: factor out a bio_await helper
  block: unify the synchronous bi_end_io callbacks
  xfs: fix number of GC bvecs
  selftests/ublk: add read-only buffer registration test
  selftests/ublk: add filesystem fio verify test for shmem_zc
  selftests/ublk: add hugetlbfs shmem_zc test for loop target
  selftests/ublk: add shared memory zero-copy test
  selftests/ublk: add UBLK_F_SHMEM_ZC support for loop target
  ...
2026-04-13 15:51:31 -07:00
2026-01-26 19:07:09 -08:00
2022-09-28 09:02:20 +02:00
2025-02-19 14:53:27 -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
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