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Ding Hui f3a9c95a15 dm: remove fake timeout to avoid leak request
Since commit 15f73f5b3e ("blk-mq: move failure injection out of
blk_mq_complete_request"), drivers are responsible for calling
blk_should_fake_timeout() at appropriate code paths and opportunities.

However, the dm driver does not implement its own timeout handler and
relies on the timeout handling of its slave devices.

If an io-timeout-fail error is injected to a dm device, the request
will be leaked and never completed, causing tasks to hang indefinitely.

Reproduce:
1. prepare dm which has iscsi slave device
2. inject io-timeout-fail to dm
   echo 1 >/sys/class/block/dm-0/io-timeout-fail
   echo 100 >/sys/kernel/debug/fail_io_timeout/probability
   echo 10 >/sys/kernel/debug/fail_io_timeout/times
3. read/write dm
4. iscsiadm -m node -u

Result: hang task like below
[  862.243768] INFO: task kworker/u514:2:151 blocked for more than 122 seconds.
[  862.244133]       Tainted: G            E       6.19.0-rc1+ #51
[  862.244337] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  862.244718] task:kworker/u514:2  state:D stack:0     pid:151   tgid:151   ppid:2      task_flags:0x4288060 flags:0x00080000
[  862.245024] Workqueue: iscsi_ctrl_3:1 __iscsi_unbind_session [scsi_transport_iscsi]
[  862.245264] Call Trace:
[  862.245587]  <TASK>
[  862.245814]  __schedule+0x810/0x15c0
[  862.246557]  schedule+0x69/0x180
[  862.246760]  blk_mq_freeze_queue_wait+0xde/0x120
[  862.247688]  elevator_change+0x16d/0x460
[  862.247893]  elevator_set_none+0x87/0xf0
[  862.248798]  blk_unregister_queue+0x12e/0x2a0
[  862.248995]  __del_gendisk+0x231/0x7e0
[  862.250143]  del_gendisk+0x12f/0x1d0
[  862.250339]  sd_remove+0x85/0x130 [sd_mod]
[  862.250650]  device_release_driver_internal+0x36d/0x530
[  862.250849]  bus_remove_device+0x1dd/0x3f0
[  862.251042]  device_del+0x38a/0x930
[  862.252095]  __scsi_remove_device+0x293/0x360
[  862.252291]  scsi_remove_target+0x486/0x760
[  862.252654]  __iscsi_unbind_session+0x18a/0x3e0 [scsi_transport_iscsi]
[  862.252886]  process_one_work+0x633/0xe50
[  862.253101]  worker_thread+0x6df/0xf10
[  862.253647]  kthread+0x36d/0x720
[  862.254533]  ret_from_fork+0x2a6/0x470
[  862.255852]  ret_from_fork_asm+0x1a/0x30
[  862.256037]  </TASK>

Remove the blk_should_fake_timeout() check from dm, as dm has no
native timeout handling and should not attempt to fake timeouts.

Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
History 2026-01-02 15:07:18 +01:00
arch RISC-V updates for v6.19-rc3 2025-12-28 09:44:26 -08:00
block block-6.19-20251218 2025-12-20 09:48:56 -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 dm-raid: fix typo in documentation 2026-01-02 15:03:53 +01:00
drivers
fs smb3 client fix 2025-12-26 16:19:45 -08:00
include regulator: Fixes for v6.19 2025-12-27 08:04:39 -08:00
init Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
io_uring io_uring-6.19-20251226 2025-12-26 11:34:38 -08:00
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 powerpc fixes for 6.19 #2 2025-12-28 09:40:09 -08:00
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