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Chaitanya Kulkarni 26bb12b9ca nvme-tcp: teardown circular locking fixes
When a controller reset is triggered via sysfs (by writing to
/sys/class/nvme/<nvmedev>/reset_controller), the reset work tears down
and re-establishes all queues. The socket release using fput() defers
the actual cleanup to task_work delayed_fput workqueue. This deferred
cleanup can race with the subsequent queue re-allocation during reset,
potentially leading to use-after-free or resource conflicts.

Replace fput() with __fput_sync() to ensure synchronous socket release,
guaranteeing that all socket resources are fully cleaned up before the
function returns. This prevents races during controller reset where
new queue setup may begin before the old socket is fully released.

* Call chain during reset:
  nvme_reset_ctrl_work()
    -> nvme_tcp_teardown_ctrl()
      -> nvme_tcp_teardown_io_queues()
        -> nvme_tcp_free_io_queues()
          -> nvme_tcp_free_queue()       <-- fput() -> __fput_sync()
      -> nvme_tcp_teardown_admin_queue()
        -> nvme_tcp_free_admin_queue()
          -> nvme_tcp_free_queue()       <-- fput() -> __fput_sync()
    -> nvme_tcp_setup_ctrl()             <-- race with deferred fput

memalloc_noreclaim_save() sets PF_MEMALLOC which is intended for tasks
performing memory reclaim work that need reserve access. While PF_MEMALLOC
prevents the task from entering direct reclaim (causing __need_reclaim() to
return false), it does not strip __GFP_IO from gfp flags. The allocator can
therefore still trigger writeback I/O when __GFP_IO remains set, which is
unsafe when the caller holds block layer locks.

Switch to memalloc_noio_save() which sets PF_MEMALLOC_NOIO. This causes
current_gfp_context() to strip __GFP_IO|__GFP_FS from every allocation in
the scope, making it safe to allocate memory while holding elevator_lock and
set->srcu.

* The issue can be reproduced using blktests:

  nvme_trtype=tcp ./check nvme/005
blktests (master) # nvme_trtype=tcp ./check nvme/005
nvme/005 (tr=tcp) (reset local loopback target)              [failed]
    runtime  0.725s  ...  0.798s
    something found in dmesg:
    [  108.473940] run blktests nvme/005 at 2025-11-22 16:12:20

    [...]
    ...
    (See '/root/blktests/results/nodev_tr_tcp/nvme/005.dmesg' for the entire message)
blktests (master) # cat /root/blktests/results/nodev_tr_tcp/nvme/005.dmesg
[  108.473940] run blktests nvme/005 at 2025-11-22 16:12:20
[  108.526983] loop0: detected capacity change from 0 to 2097152
[  108.555606] nvmet: adding nsid 1 to subsystem blktests-subsystem-1
[  108.572531] nvmet_tcp: enabling port 0 (127.0.0.1:4420)
[  108.613061] nvmet: Created nvm controller 1 for subsystem blktests-subsystem-1 for NQN nqn.2014-08.org.nvmexpress:uuid:0f01fb42-9f7f-4856-b0b3-51e60b8de349.
[  108.616832] nvme nvme0: creating 48 I/O queues.
[  108.630791] nvme nvme0: mapped 48/0/0 default/read/poll queues.
[  108.661892] nvme nvme0: new ctrl: NQN "blktests-subsystem-1", addr 127.0.0.1:4420, hostnqn: nqn.2014-08.org.nvmexpress:uuid:0f01fb42-9f7f-4856-b0b3-51e60b8de349
[  108.746639] nvmet: Created nvm controller 2 for subsystem blktests-subsystem-1 for NQN nqn.2014-08.org.nvmexpress:uuid:0f01fb42-9f7f-4856-b0b3-51e60b8de349.
[  108.748466] nvme nvme0: creating 48 I/O queues.
[  108.802984] nvme nvme0: mapped 48/0/0 default/read/poll queues.
[  108.829983] nvme nvme0: Removing ctrl: NQN "blktests-subsystem-1"
[  108.854288] block nvme0n1: no available path - failing I/O
[  108.854344] block nvme0n1: no available path - failing I/O
[  108.854373] Buffer I/O error on dev nvme0n1, logical block 1, async page read

[  108.891693] ======================================================
[  108.895912] WARNING: possible circular locking dependency detected
[  108.900184] 6.17.0nvme+ #3 Tainted: G                 N
[  108.903913] ------------------------------------------------------
[  108.908171] nvme/2734 is trying to acquire lock:
[  108.911957] ffff88810210e610 (set->srcu){.+.+}-{0:0}, at: __synchronize_srcu+0x17/0x170
[  108.917587]
               but task is already holding lock:
[  108.921570] ffff88813abea198 (&q->elevator_lock){+.+.}-{4:4}, at: elevator_change+0xa8/0x1c0
[  108.927361]
               which lock already depends on the new lock.

[  108.933018]
               the existing dependency chain (in reverse order) is:
[  108.938223]
               -> #4 (&q->elevator_lock){+.+.}-{4:4}:
[  108.942988]        __mutex_lock+0xa2/0x1150
[  108.945873]        elevator_change+0xa8/0x1c0
[  108.948925]        elv_iosched_store+0xdf/0x140
[  108.952043]        kernfs_fop_write_iter+0x16a/0x220
[  108.955367]        vfs_write+0x378/0x520
[  108.957598]        ksys_write+0x67/0xe0
[  108.959721]        do_syscall_64+0x76/0xbb0
[  108.962052]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  108.965145]
               -> #3 (&q->q_usage_counter(io)){++++}-{0:0}:
[  108.968923]        blk_alloc_queue+0x30e/0x350
[  108.972117]        blk_mq_alloc_queue+0x61/0xd0
[  108.974677]        scsi_alloc_sdev+0x2a0/0x3e0
[  108.977092]        scsi_probe_and_add_lun+0x1bd/0x430
[  108.979921]        __scsi_add_device+0x109/0x120
[  108.982504]        ata_scsi_scan_host+0x97/0x1c0
[  108.984365]        async_run_entry_fn+0x2d/0x130
[  108.986109]        process_one_work+0x20e/0x630
[  108.987830]        worker_thread+0x184/0x330
[  108.989473]        kthread+0x10a/0x250
[  108.990852]        ret_from_fork+0x297/0x300
[  108.992491]        ret_from_fork_asm+0x1a/0x30
[  108.994159]
               -> #2 (fs_reclaim){+.+.}-{0:0}:
[  108.996320]        fs_reclaim_acquire+0x99/0xd0
[  108.998058]        kmem_cache_alloc_node_noprof+0x4e/0x3c0
[  109.000123]        __alloc_skb+0x15f/0x190
[  109.002195]        tcp_send_active_reset+0x3f/0x1e0
[  109.004038]        tcp_disconnect+0x50b/0x720
[  109.005695]        __tcp_close+0x2b8/0x4b0
[  109.007227]        tcp_close+0x20/0x80
[  109.008663]        inet_release+0x31/0x60
[  109.010175]        __sock_release+0x3a/0xc0
[  109.011778]        sock_close+0x14/0x20
[  109.013263]        __fput+0xee/0x2c0
[  109.014673]        delayed_fput+0x31/0x50
[  109.016183]        process_one_work+0x20e/0x630
[  109.017897]        worker_thread+0x184/0x330
[  109.019543]        kthread+0x10a/0x250
[  109.020929]        ret_from_fork+0x297/0x300
[  109.022565]        ret_from_fork_asm+0x1a/0x30
[  109.024194]
               -> #1 (sk_lock-AF_INET-NVME){+.+.}-{0:0}:
[  109.026634]        lock_sock_nested+0x2e/0x70
[  109.028251]        tcp_sendmsg+0x1a/0x40
[  109.029783]        sock_sendmsg+0xed/0x110
[  109.031321]        nvme_tcp_try_send_cmd_pdu+0x13e/0x260 [nvme_tcp]
[  109.034263]        nvme_tcp_try_send+0xb3/0x330 [nvme_tcp]
[  109.036375]        nvme_tcp_queue_rq+0x342/0x3d0 [nvme_tcp]
[  109.038528]        blk_mq_dispatch_rq_list+0x297/0x800
[  109.040448]        __blk_mq_sched_dispatch_requests+0x3db/0x5f0
[  109.042677]        blk_mq_sched_dispatch_requests+0x29/0x70
[  109.044787]        blk_mq_run_work_fn+0x76/0x1b0
[  109.046535]        process_one_work+0x20e/0x630
[  109.048245]        worker_thread+0x184/0x330
[  109.049890]        kthread+0x10a/0x250
[  109.051331]        ret_from_fork+0x297/0x300
[  109.053024]        ret_from_fork_asm+0x1a/0x30
[  109.054740]
               -> #0 (set->srcu){.+.+}-{0:0}:
[  109.056850]        __lock_acquire+0x1468/0x2210
[  109.058614]        lock_sync+0xa5/0x110
[  109.060048]        __synchronize_srcu+0x49/0x170
[  109.061802]        elevator_switch+0xc9/0x330
[  109.063950]        elevator_change+0x128/0x1c0
[  109.065675]        elevator_set_none+0x4c/0x90
[  109.067316]        blk_unregister_queue+0xa8/0x110
[  109.069165]        __del_gendisk+0x14e/0x3c0
[  109.070824]        del_gendisk+0x75/0xa0
[  109.072328]        nvme_ns_remove+0xf2/0x230 [nvme_core]
[  109.074365]        nvme_remove_namespaces+0xf2/0x150 [nvme_core]
[  109.076652]        nvme_do_delete_ctrl+0x71/0x90 [nvme_core]
[  109.078775]        nvme_delete_ctrl_sync+0x3b/0x50 [nvme_core]
[  109.081009]        nvme_sysfs_delete+0x34/0x40 [nvme_core]
[  109.083082]        kernfs_fop_write_iter+0x16a/0x220
[  109.085009]        vfs_write+0x378/0x520
[  109.086539]        ksys_write+0x67/0xe0
[  109.087982]        do_syscall_64+0x76/0xbb0
[  109.089577]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  109.091665]
               other info that might help us debug this:

[  109.095478] Chain exists of:
                 set->srcu --> &q->q_usage_counter(io) --> &q->elevator_lock

[  109.099544]  Possible unsafe locking scenario:

[  109.101708]        CPU0                    CPU1
[  109.103402]        ----                    ----
[  109.105103]   lock(&q->elevator_lock);
[  109.106530]                                lock(&q->q_usage_counter(io));
[  109.109022]                                lock(&q->elevator_lock);
[  109.111391]   sync(set->srcu);
[  109.112586]
                *** DEADLOCK ***

[  109.114772] 5 locks held by nvme/2734:
[  109.116189]  #0: ffff888101925410 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0x67/0xe0
[  109.119143]  #1: ffff88817a914e88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x10f/0x220
[  109.123141]  #2: ffff8881046313f8 (kn->active#185){++++}-{0:0}, at: sysfs_remove_file_self+0x26/0x50
[  109.126543]  #3: ffff88810470e1d0 (&set->update_nr_hwq_lock){++++}-{4:4}, at: del_gendisk+0x6d/0xa0
[  109.129891]  #4: ffff88813abea198 (&q->elevator_lock){+.+.}-{4:4}, at: elevator_change+0xa8/0x1c0
[  109.133149]
               stack backtrace:
[  109.134817] CPU: 6 UID: 0 PID: 2734 Comm: nvme Tainted: G                 N  6.17.0nvme+ #3 PREEMPT(voluntary)
[  109.134819] Tainted: [N]=TEST
[  109.134820] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[  109.134821] Call Trace:
[  109.134823]  <TASK>
[  109.134824]  dump_stack_lvl+0x75/0xb0
[  109.134828]  print_circular_bug+0x26a/0x330
[  109.134831]  check_noncircular+0x12f/0x150
[  109.134834]  __lock_acquire+0x1468/0x2210
[  109.134837]  ? __synchronize_srcu+0x17/0x170
[  109.134838]  lock_sync+0xa5/0x110
[  109.134840]  ? __synchronize_srcu+0x17/0x170
[  109.134842]  __synchronize_srcu+0x49/0x170
[  109.134843]  ? mark_held_locks+0x49/0x80
[  109.134845]  ? _raw_spin_unlock_irqrestore+0x2d/0x60
[  109.134847]  ? kvm_clock_get_cycles+0x14/0x30
[  109.134853]  ? ktime_get_mono_fast_ns+0x36/0xb0
[  109.134858]  elevator_switch+0xc9/0x330
[  109.134860]  elevator_change+0x128/0x1c0
[  109.134862]  ? kernfs_put.part.0+0x86/0x290
[  109.134864]  elevator_set_none+0x4c/0x90
[  109.134866]  blk_unregister_queue+0xa8/0x110
[  109.134868]  __del_gendisk+0x14e/0x3c0
[  109.134870]  del_gendisk+0x75/0xa0
[  109.134872]  nvme_ns_remove+0xf2/0x230 [nvme_core]
[  109.134879]  nvme_remove_namespaces+0xf2/0x150 [nvme_core]
[  109.134887]  nvme_do_delete_ctrl+0x71/0x90 [nvme_core]
[  109.134893]  nvme_delete_ctrl_sync+0x3b/0x50 [nvme_core]
[  109.134899]  nvme_sysfs_delete+0x34/0x40 [nvme_core]
[  109.134905]  kernfs_fop_write_iter+0x16a/0x220
[  109.134908]  vfs_write+0x378/0x520
[  109.134911]  ksys_write+0x67/0xe0
[  109.134913]  do_syscall_64+0x76/0xbb0
[  109.134915]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  109.134916] RIP: 0033:0x7fd68a737317
[  109.134917] Code: 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
[  109.134919] RSP: 002b:00007ffded1546d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[  109.134920] RAX: ffffffffffffffda RBX: 000000000054f7e0 RCX: 00007fd68a737317
[  109.134921] RDX: 0000000000000001 RSI: 00007fd68a855719 RDI: 0000000000000003
[  109.134921] RBP: 0000000000000003 R08: 0000000030407850 R09: 00007fd68a7cd4e0
[  109.134922] R10: 00007fd68a65b130 R11: 0000000000000246 R12: 00007fd68a855719
[  109.134923] R13: 00000000304074c0 R14: 00000000304074c0 R15: 0000000030408660
[  109.134926]  </TASK>
[  109.962756] Key type psk unregistered

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-04-22 10:07:30 -07:00
arch EFI fixes for v7.0 #2 2026-03-08 12:13:09 -07:00
block blk-wbt: remove WARN_ON_ONCE from wbt_init_enable_default() 2026-04-06 12:54:03 -06:00
certs Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
crypto crypto: remove HKDF library 2026-03-27 07:35:03 -07:00
Documentation blk-crypto: fix name of the bio completion callback 2026-04-02 07:09:03 -06:00
drivers nvme-tcp: teardown circular locking fixes 2026-04-22 10:07:30 -07:00
fs Merge branch 'for-7.1/block-integrity' into for-7.1/block 2026-03-09 14:30:14 -06:00
include block: remove unused BVEC_ITER_ALL_INIT 2026-04-04 08:10:37 -06:00
init io_uring-7.0-20260305 2026-03-06 08:31:36 -08:00
io_uring io_uring-7.0-20260305 2026-03-06 08:31:36 -08:00
ipc Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kernel Make clock_adjtime() syscall timex validation slightly more 2026-03-07 17:09:15 -08:00
lib linux_kselftest-kunit-fixes-7.0-rc3 2026-03-06 12:34:49 -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 block: remove bdev_nonrot() 2026-03-09 14:30:00 -06:00
net xdp: produce a warning when calculated tailroom is negative 2026-03-05 08:02:05 -08:00
rust linux_kselftest-kunit-fixes-7.0-rc3 2026-03-06 12:34:49 -08:00
samples USB / Thunderbolt changes for 7.0-rc1 2026-02-17 09:36:43 -08:00
scripts kbuild: install-extmod-build: Package resolve_btfids if necessary 2026-02-26 14:49:34 -07:00
security Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
sound ASoC: Fixes for v7.0 2026-03-05 17:22:14 +01:00
tools selftests: ublk: test that teardown after incomplete recovery completes 2026-04-06 08:37:48 -06:00
usr kbuild: uapi: drop dependency on CC_CAN_LINK 2026-01-16 15:02:11 -07:00
virt KVM: always define KVM_CAP_SYNC_MMU 2026-02-28 15:31:35 +01:00
.clang-format Devicetree updates for v7.0: 2026-02-11 18:27:08 -08:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig editorconfig: add rst extension 2026-01-26 19:07:09 -08:00
.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 linux_kselftest-kunit-fixes-7.0-rc3 2026-03-06 12:34:49 -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 MAINTAINERS: remove Thomas Falcon from IBM ibmvnic 2026-03-05 07:35:45 -08:00
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 hwmon fixes for v7.0-rc3 2026-03-07 08:39:59 -08:00
Makefile Linux 7.0-rc3 2026-03-08 16:56:54 -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
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* Hardware Vendor - Writing drivers for new hardware
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* 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