---
id: CVE-2026-93254
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  arm64: entry: Avoid unnecessary local_irq_disable() on kernel exit

  Currently, when exiting to kernel mode, we attempt involuntary
  preemption
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  arm64: entry: Avoid unnecessary local_irq_disable() on kernel exit

  Currently, when exiting to kernel mode, we attempt involuntary
  preemption. The preemption logic expe…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= ae654112eac05f316ef31587fc55e4d7160d0086 <
    49a61174186bed25d439ff37400c7ce5e3603e73
  - >-
    Linux >= ae654112eac05f316ef31587fc55e4d7160d0086 <
    39aebe0e89469c2904e60b1e977e0d4dbf33326b
  - Linux 7.1
published: '2026-09-24'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T16:17:21.807'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-93254'
references:
  - url: 'https://git.kernel.org/stable/c/39aebe0e89469c2904e60b1e977e0d4dbf33326b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/49a61174186bed25d439ff37400c7ce5e3603e73'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-24T16:47:15.833Z'
epss: 0.0021
epssPercentile: 0.10048
---

## Overview

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

arm64: entry: Avoid unnecessary local_irq_disable() on kernel exit

Currently, when exiting to kernel mode, we attempt involuntary
preemption. The preemption logic expects IRQs to be disabled, which is
why we call local_irq_disable() before attempting preemption.

However, depending on the context, local_irq_disable() may be
unnecessary:

- __el1_irq(), the non-NMI EL1 IRQ path, already has IRQs disabled, so
  local_irq_disable() is redundant.

- irqentry_exit_to_kernel_mode_preempt() immediately returns when
  exiting from an NMI-like context, so calling local_irq_disable()
  beforehand is unnecessary work.

Furthermore, it confuses the pNMI state tracking when we are in a
context with interrupts disabled and the GIC_PRIO_PSR_I_SET bit is set
in the PMR, leading to a warning when
CONFIG_ARM64_DEBUG_PRIORITY_MASKING=y:

     WARNING: ./arch/arm64/include/asm/irqflags.h:63 at arm64_exit_to_kernel_mode+0xb8/0xc0, CPU#40: retsnoop/31805
     CPU: 40 UID: 0 PID: 31805 Comm: retsnoop Not tainted 7.2.0-rc6-next-20260805 #7 PREEMPTLAZY
     pstate: 234013c9 (nzCv DAIF +PAN -UAO +TCO +DIT +SSBS BTYPE=--)
     pc : arm64_exit_to_kernel_mode (arch/arm64/kernel/entry-common.c:63)
     lr : el1_abort (arch/arm64/kernel/entry-common.c:323)
     pmr: 000000f0
     Call trace:
      arm64_exit_to_kernel_mode (arch/arm64/kernel/entry-common.c:63) (P)
      el1_abort (arch/arm64/kernel/entry-common.c:323)
      el1h_64_sync_handler (arch/arm64/kernel/entry-common.c:449)
      el1h_64_sync (arch/arm64/kernel/entry.S:589)
      [...]

Split arm64_exit_to_kernel_mode() into preempt, non-preempt, and
dispatch parts so that we can avoid this extra work where it is not
needed and avoid breaking the pNMI tracking logic.

## Remediation

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