---
id: CVE-2025-71117
title: 'block: Remove queue freezing from several sysfs store callbacks'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  block: Remove queue freezing from several sysfs store callbacks

  Freezing the request queue from inside sysfs store callbacks may cause a
  deadlock in combination with t…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= af2814149883e2c1851866ea2afcd8eadc040f79 <
    3997b3147c7b68b0308378fa95a766015f8ceb1c
  - >-
    Linux >= af2814149883e2c1851866ea2afcd8eadc040f79 <
    935a20d1bebf6236076785fac3ff81e3931834e9
  - Linux 6.11
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T21:14:13.909970Z'
published: '2026-01-14'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T21:23:08.667Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2025-71117'
references:
  - url: 'https://git.kernel.org/stable/c/3997b3147c7b68b0308378fa95a766015f8ceb1c'
  - url: 'https://git.kernel.org/stable/c/935a20d1bebf6236076785fac3ff81e3931834e9'
tags:
  - cve.org
epss: 0.00098
epssPercentile: 0.00743
ingestedAt: '2026-11-05T22:38:32.050Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

block: Remove queue freezing from several sysfs store callbacks

Freezing the request queue from inside sysfs store callbacks may cause a
deadlock in combination with the dm-multipath driver and the
queue_if_no_path option. Additionally, freezing the request queue slows
down system boot on systems where sysfs attributes are set synchronously.

Fix this by removing the blk_mq_freeze_queue() / blk_mq_unfreeze_queue()
calls from the store callbacks that do not strictly need these callbacks.
Add the __data_racy annotation to request_queue.rq_timeout to suppress
KCSAN data race reports about the rq_timeout reads.

This patch may cause a small delay in applying the new settings.

For all the attributes affected by this patch, I/O will complete
correctly whether the old or the new value of the attribute is used.

This patch affects the following sysfs attributes:
* io_poll_delay
* io_timeout
* nomerges
* read_ahead_kb
* rq_affinity

Here is an example of a deadlock triggered by running test srp/002
if this patch is not applied:

task:multipathd
Call Trace:
 <TASK>
 __schedule+0x8c1/0x1bf0
 schedule+0xdd/0x270
 schedule_preempt_disabled+0x1c/0x30
 __mutex_lock+0xb89/0x1650
 mutex_lock_nested+0x1f/0x30
 dm_table_set_restrictions+0x823/0xdf0
 __bind+0x166/0x590
 dm_swap_table+0x2a7/0x490
 do_resume+0x1b1/0x610
 dev_suspend+0x55/0x1a0
 ctl_ioctl+0x3a5/0x7e0
 dm_ctl_ioctl+0x12/0x20
 __x64_sys_ioctl+0x127/0x1a0
 x64_sys_call+0xe2b/0x17d0
 do_syscall_64+0x96/0x3a0
 entry_SYSCALL_64_after_hwframe+0x4b/0x53
 </TASK>
task:(udev-worker)
Call Trace:
 <TASK>
 __schedule+0x8c1/0x1bf0
 schedule+0xdd/0x270
 blk_mq_freeze_queue_wait+0xf2/0x140
 blk_mq_freeze_queue_nomemsave+0x23/0x30
 queue_ra_store+0x14e/0x290
 queue_attr_store+0x23e/0x2c0
 sysfs_kf_write+0xde/0x140
 kernfs_fop_write_iter+0x3b2/0x630
 vfs_write+0x4fd/0x1390
 ksys_write+0xfd/0x230
 __x64_sys_write+0x76/0xc0
 x64_sys_call+0x276/0x17d0
 do_syscall_64+0x96/0x3a0
 entry_SYSCALL_64_after_hwframe+0x4b/0x53
 </TASK>

## Affected

- `Linux >= af2814149883e2c1851866ea2afcd8eadc040f79 < 3997b3147c7b68b0308378fa95a766015f8ceb1c`
- `Linux >= af2814149883e2c1851866ea2afcd8eadc040f79 < 935a20d1bebf6236076785fac3ff81e3931834e9`
- `Linux 6.11`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.