---
id: CVE-2022-49841
title: 'serial: imx: Add missing .thaw_noirq hook'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  serial: imx: Add missing .thaw_noirq hook

  The following warning is seen with non-console UART instance when
  system hibernates.

  [   37.371969] ------------[ cut here ]…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 09df0b3464e528c6a4ca2c48d9ff6d2fd7cbd775 <
    e401312ca6e180ee1bd65f6a766e99dd40aa95e7
  - >-
    Linux >= 09df0b3464e528c6a4ca2c48d9ff6d2fd7cbd775 <
    476b09e07bd519ec7ba5941a6a6f9a02256dbb21
  - >-
    Linux >= 09df0b3464e528c6a4ca2c48d9ff6d2fd7cbd775 <
    0a3160f4ffc70ee4bfa1521f698dace06e6091fd
  - >-
    Linux >= 09df0b3464e528c6a4ca2c48d9ff6d2fd7cbd775 <
    ae22294e213a402a70fa1731538367d1b758ffe7
  - >-
    Linux >= 09df0b3464e528c6a4ca2c48d9ff6d2fd7cbd775 <
    e3f9d87d6f0732827c443bd1474df21c2fad704b
  - >-
    Linux >= 09df0b3464e528c6a4ca2c48d9ff6d2fd7cbd775 <
    4561d8008a467cb05ac632a215391d6b787f40aa
  - Linux 4.16
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T19:50:44.550163Z'
published: '2025-05-01'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T20:00:09.625Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2022-49841'
references:
  - url: 'https://git.kernel.org/stable/c/e401312ca6e180ee1bd65f6a766e99dd40aa95e7'
  - url: 'https://git.kernel.org/stable/c/476b09e07bd519ec7ba5941a6a6f9a02256dbb21'
  - url: 'https://git.kernel.org/stable/c/0a3160f4ffc70ee4bfa1521f698dace06e6091fd'
  - url: 'https://git.kernel.org/stable/c/ae22294e213a402a70fa1731538367d1b758ffe7'
  - url: 'https://git.kernel.org/stable/c/e3f9d87d6f0732827c443bd1474df21c2fad704b'
  - url: 'https://git.kernel.org/stable/c/4561d8008a467cb05ac632a215391d6b787f40aa'
tags:
  - cve.org
epss: 0.00202
epssPercentile: 0.10259
ingestedAt: '2026-11-05T22:38:31.619Z'
---

## Overview

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

serial: imx: Add missing .thaw_noirq hook

The following warning is seen with non-console UART instance when
system hibernates.

[   37.371969] ------------[ cut here ]------------
[   37.376599] uart3_root_clk already disabled
[   37.380810] WARNING: CPU: 0 PID: 296 at drivers/clk/clk.c:952 clk_core_disable+0xa4/0xb0
...
[   37.506986] Call trace:
[   37.509432]  clk_core_disable+0xa4/0xb0
[   37.513270]  clk_disable+0x34/0x50
[   37.516672]  imx_uart_thaw+0x38/0x5c
[   37.520250]  platform_pm_thaw+0x30/0x6c
[   37.524089]  dpm_run_callback.constprop.0+0x3c/0xd4
[   37.528972]  device_resume+0x7c/0x160
[   37.532633]  dpm_resume+0xe8/0x230
[   37.536036]  hibernation_snapshot+0x288/0x430
[   37.540397]  hibernate+0x10c/0x2e0
[   37.543798]  state_store+0xc4/0xd0
[   37.547203]  kobj_attr_store+0x1c/0x30
[   37.550953]  sysfs_kf_write+0x48/0x60
[   37.554619]  kernfs_fop_write_iter+0x118/0x1ac
[   37.559063]  new_sync_write+0xe8/0x184
[   37.562812]  vfs_write+0x230/0x290
[   37.566214]  ksys_write+0x68/0xf4
[   37.569529]  __arm64_sys_write+0x20/0x2c
[   37.573452]  invoke_syscall.constprop.0+0x50/0xf0
[   37.578156]  do_el0_svc+0x11c/0x150
[   37.581648]  el0_svc+0x30/0x140
[   37.584792]  el0t_64_sync_handler+0xe8/0xf0
[   37.588976]  el0t_64_sync+0x1a0/0x1a4
[   37.592639] ---[ end trace 56e22eec54676d75 ]---

On hibernating, pm core calls into related hooks in sequence like:

    .freeze
    .freeze_noirq
    .thaw_noirq
    .thaw

With .thaw_noirq hook being absent, the clock will be disabled in a
unbalanced call which results the warning above.

    imx_uart_freeze()
        clk_prepare_enable()
    imx_uart_suspend_noirq()
        clk_disable()
    imx_uart_thaw
        clk_disable_unprepare()

Adding the missing .thaw_noirq hook as imx_uart_resume_noirq() will have
the call sequence corrected as below and thus fix the warning.

    imx_uart_freeze()
        clk_prepare_enable()
    imx_uart_suspend_noirq()
        clk_disable()
    imx_uart_resume_noirq()
        clk_enable()
    imx_uart_thaw
        clk_disable_unprepare()

## Affected

- `Linux >= 09df0b3464e528c6a4ca2c48d9ff6d2fd7cbd775 < e401312ca6e180ee1bd65f6a766e99dd40aa95e7`
- `Linux >= 09df0b3464e528c6a4ca2c48d9ff6d2fd7cbd775 < 476b09e07bd519ec7ba5941a6a6f9a02256dbb21`
- `Linux >= 09df0b3464e528c6a4ca2c48d9ff6d2fd7cbd775 < 0a3160f4ffc70ee4bfa1521f698dace06e6091fd`
- `Linux >= 09df0b3464e528c6a4ca2c48d9ff6d2fd7cbd775 < ae22294e213a402a70fa1731538367d1b758ffe7`
- `Linux >= 09df0b3464e528c6a4ca2c48d9ff6d2fd7cbd775 < e3f9d87d6f0732827c443bd1474df21c2fad704b`
- `Linux >= 09df0b3464e528c6a4ca2c48d9ff6d2fd7cbd775 < 4561d8008a467cb05ac632a215391d6b787f40aa`
- `Linux 4.16`

## Remediation

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