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John Garry ac30cd3043 nvme: stop using AWUPF
As described at [0], much of the atomic write parts of the specification
are lacking.

For now, there is nothing which we can do in software about the lack of
a dedicated NVMe write atomic command.

As for reading the atomic write limits, it is felt that the per-namespace
values are mostly properly specified and it is assumed that they are
properly implemented.

The specification of NAWUPF is quite clear. However the specification of
NABSPF is less clear. The lack of clarity in NABSPF comes from deciding
whether NABSPF applies when NSABP is 0 - it is assumed that NSABPF does
not apply when NSABP is 0.

As for the per-controller AWUPF, how this value applies to shared
namespaces is missing in the specification. Furthermore, the value is in
terms of logical blocks, which is an NS entity.

Since AWUPF is so poorly defined, stop using it already together.
Hopefully this will force vendors to implement NAWUPF support always.

Note that AWUPF not only effects atomic write support, but also the
physical block size reported for the device.

To help users know this restriction, log an info message per NS.

[0] https://lore.kernel.org/linux-nvme/20250707141834.GA30198@lst.de/

Tested-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-01-28 07:02:38 -08:00
arch RISC-V updates for v6.19-rc3 2025-12-28 09:44:26 -08:00
block block, nvme: remove unused dma_iova_state function parameter 2026-01-13 07:23:39 -07:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto Networking changes for 6.19. 2025-12-03 17:24:33 -08:00
Documentation blk-crypto: handle the fallback above the block layer 2026-01-11 12:55:41 -07:00
drivers nvme: stop using AWUPF 2026-01-28 07:02:38 -08:00
fs blk-crypto: handle the fallback above the block layer 2026-01-11 12:55:41 -07:00
include block, nvme: remove unused dma_iova_state function parameter 2026-01-13 07:23:39 -07:00
init Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
io_uring io_uring: remove nr_segs recalculation in io_import_kbuf() 2026-01-07 08:06:33 -07:00
ipc Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
kernel EFI fixes for v6.19 #1 2025-12-26 13:37:11 -08:00
lib linux_kselftest-kunit-fixes-6.19-rc3 2025-12-20 11:59:06 -08:00
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 slab fix for 6.19-rc2 2025-12-20 11:24:42 -08:00
net nfsd-6.19 fixes: 2025-12-24 09:23:04 -08:00
rust rust: dma: add helpers for architectures without CONFIG_HAS_DMA 2025-12-16 13:20:14 +01:00
samples samples: rust: fix endianness issue in rust_driver_pci 2025-12-17 18:10:58 +01:00
scripts Coccinelle: pm_runtime: Fix typo in report message 2025-12-21 21:04:52 +01:00
security Trivial optimization. 2025-12-14 15:21:02 +12:00
sound ALSA: hda/realtek: fix PCI SSID for one of the HP 200 G2i laptop 2025-12-21 11:19:31 +01:00
tools selftests: ublk: add stop command with --safe option 2026-01-12 15:07:31 -07:00
usr initramfs: add gen_init_cpio to hostprogs unconditionally 2025-11-26 21:55:40 +01:00
virt KVM fixes for 6.19-rc1 2025-12-18 18:38:45 +01:00
.clang-format s390/pci: Fix cyclic dead-lock in zpci_zdev_put() and zpci_scan_devices() 2025-12-14 11:03:58 +01:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: remove Alyssa Rosenzweig 2025-09-18 21:17:31 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore rust: kbuild: add proc macro library support 2025-11-24 17:15:36 +01:00
.mailmap Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
.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 Including fixes from netfilter and CAN. 2025-12-19 07:55:35 +12:00
Kbuild sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS regulator: Add UAPI headers to MAINTAINERS 2025-12-22 09:00:43 +00:00
Makefile Linux 6.19-rc3 2025-12-28 13:24:26 -08:00
README README: restructure with role-based documentation and guidelines 2025-11-29 08:40:33 -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


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



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