# CVE-2026-89922: KVM: s390: Take srcu when importing watchpoint data

CVE-2026-89922 is fixed in 2 products on 1 platform, first by DEBIAN-CVE-2026-89922, released September 23, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-89922
- Priority: High
- CVSS: 7.8 (Important)
- EPSS: 0.0016
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 16, 2026
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-89922

## Description

In the Linux kernel, the following vulnerability has been resolved:  KVM: s390: Take srcu when importing watchpoint data  __import_wp_info() backs up the original guest memory contents of a watchpoint with read_guest_abs(), which is kvm_read_guest() and therefore resolves the memslot via __kvm_memslots(). That requires kvm->srcu (or kvm->slots_lock) to be held, otherwise a concurrent memslot update can free the memslots array under us once its SRCU grace period has elapsed.  As this is not fast path, following lock ordering (mutex first, then srcu) take the big hammer and hold the srcu for the full import.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 6.1.190-1 | [DEBIAN-CVE-2026-89922](https://patchblox.com/security/data/fix/linux/debian-cve-2026-89922.md) | Sep 23, 2026 |
| Linux | linux Debian 13.5 (trixie) | 6.12.111-1 | [DEBIAN-CVE-2026-89922](https://patchblox.com/security/data/fix/linux/debian-cve-2026-89922.md) | Sep 23, 2026 |
| Linux | linux Debian 14 | 7.2.6-1 | [DEBIAN-CVE-2026-89922](https://patchblox.com/security/data/fix/linux/debian-cve-2026-89922.md) | Sep 23, 2026 |
| Linux | linux-6.12 Debian 12.15 (bookworm) | 6.12.111-1~deb12u1 | [DEBIAN-CVE-2026-89922](https://patchblox.com/security/data/fix/linux/debian-cve-2026-89922.md) | Sep 23, 2026 |

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Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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