Linux kernel source tree
Go to file
Gerd Bayer 6a107cfe9c net/mlx5: Fix double unregister of HCA_PORTS component
Clear hca_devcom_comp in device's private data after unregistering it in
LAG teardown. Otherwise a slightly lagging second pass through
mlx5_unload_one() might try to unregister it again and trip over
use-after-free.

On s390 almost all PCI level recovery events trigger two passes through
mxl5_unload_one() - one through the poll_health() method and one through
mlx5_pci_err_detected() as callback from generic PCI error recovery.
While testing PCI error recovery paths with more kernel debug features
enabled, this issue reproducibly led to kernel panics with the following
call chain:

 Unable to handle kernel pointer dereference in virtual kernel address space
 Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6803 ESOP-2 FSI
 Fault in home space mode while using kernel ASCE.
 AS:00000000705c4007 R3:0000000000000024
 Oops: 0038 ilc:3 [#1]SMP

 CPU: 14 UID: 0 PID: 156 Comm: kmcheck Kdump: loaded Not tainted
      6.18.0-20251130.rc7.git0.16131a59cab1.300.fc43.s390x+debug #1 PREEMPT

 Krnl PSW : 0404e00180000000 0000020fc86aa1dc (__lock_acquire+0x5c/0x15f0)
            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
 Krnl GPRS: 0000000000000000 0000020f00000001 6b6b6b6b6b6b6c33 0000000000000000
            0000000000000000 0000000000000000 0000000000000001 0000000000000000
            0000000000000000 0000020fca28b820 0000000000000000 0000010a1ced8100
            0000010a1ced8100 0000020fc9775068 0000018fce14f8b8 0000018fce14f7f8
 Krnl Code: 0000020fc86aa1cc: e3b003400004        lg      %r11,832
            0000020fc86aa1d2: a7840211           brc     8,0000020fc86aa5f4
           *0000020fc86aa1d6: c09000df0b25       larl    %r9,0000020fca28b820
           >0000020fc86aa1dc: d50790002000       clc     0(8,%r9),0(%r2)
            0000020fc86aa1e2: a7840209           brc     8,0000020fc86aa5f4
            0000020fc86aa1e6: c0e001100401       larl    %r14,0000020fca8aa9e8
            0000020fc86aa1ec: c01000e25a00       larl    %r1,0000020fca2f55ec
            0000020fc86aa1f2: a7eb00e8           aghi    %r14,232

 Call Trace:
  __lock_acquire+0x5c/0x15f0
  lock_acquire.part.0+0xf8/0x270
  lock_acquire+0xb0/0x1b0
  down_write+0x5a/0x250
  mlx5_detach_device+0x42/0x110 [mlx5_core]
  mlx5_unload_one_devl_locked+0x50/0xc0 [mlx5_core]
  mlx5_unload_one+0x42/0x60 [mlx5_core]
  mlx5_pci_err_detected+0x94/0x150 [mlx5_core]
  zpci_event_attempt_error_recovery+0xcc/0x388

Fixes: 5a977b5833 ("net/mlx5: Lag, move devcom registration to LAG layer")
Signed-off-by: Gerd Bayer <gbayer@linux.ibm.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Acked-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20251202-fix_lag-v1-1-59e8177ffce0@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-12-04 15:29:13 +01:00
arch Networking changes for 6.19. 2025-12-03 17:24:33 -08:00
block vfs-6.19-rc1.inode 2025-12-01 09:02:34 -08:00
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 Networking changes for 6.19. 2025-12-03 17:24:33 -08:00
drivers net/mlx5: Fix double unregister of HCA_PORTS component 2025-12-04 15:29:13 +01:00
fs Networking changes for 6.19. 2025-12-03 17:24:33 -08:00
include Networking changes for 6.19. 2025-12-03 17:24:33 -08:00
init Kbuild updates for v6.19 2025-12-03 14:42:21 -08:00
io_uring vfs-6.19-rc1.fd_prepare.fs 2025-12-01 17:32:07 -08:00
ipc vfs-6.19-rc1.fd_prepare.fs 2025-12-01 17:32:07 -08:00
kernel Networking changes for 6.19. 2025-12-03 17:24:33 -08:00
lib bpf-next-6.19 2025-12-03 16:54:54 -08:00
LICENSES LICENSES: Replace the obsolete address of the FSF in the GFDL-1.2 2025-07-24 11:15:39 +02:00
mm slab updates for 6.19 2025-12-03 11:53:47 -08:00
net net/sched: ets: Always remove class from active list before deleting in ets_qdisc_change 2025-12-04 11:43:45 +01:00
rust Rust changes for v6.19 2025-12-03 14:16:49 -08:00
samples Networking changes for 6.19. 2025-12-03 17:24:33 -08:00
scripts Kbuild updates for v6.19 2025-12-03 14:42:21 -08:00
security This update includes the following changes: 2025-12-03 11:28:38 -08:00
sound ALSA: hda/realtek: Add quirk for HP ProBook 450 G8 2025-11-26 07:26:56 +01:00
tools Networking changes for 6.19. 2025-12-03 17:24:33 -08:00
usr initramfs: add gen_init_cpio to hostprogs unconditionally 2025-11-26 21:55:40 +01:00
virt A large overhaul of the restartable sequences and CID management: 2025-12-02 08:48:53 -08:00
.clang-format memblock: drop for_each_free_mem_pfn_range_in_zone_from() 2025-09-14 08:49:03 +03:00
.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: 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 Kbuild updates for v6.19 2025-12-03 14:42:21 -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: mark ISDN subsystem as orphan 2025-10-27 17:49:45 -07:00
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 Networking changes for 6.19. 2025-12-03 17:24:33 -08:00
Makefile Kbuild updates for v6.19 2025-12-03 14:42:21 -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