# CVE-2026-72173: fs/proc/task\_mmu: do not warn on seeing non-migration pmd entry

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-08-15 · Updated: 2026-08-17

## Affected

- Linux: version range not reported
- Linux: 6.19

## Description

In the Linux kernel, the following vulnerability has been resolved: fs/proc/task_mmu: do not warn on seeing non-migration pmd entry Patch series "mm/hmm: A fix and a selftest", v3. Patch 1 fixes a stale warning present from the time when only migration softleaf entries were supported at the PMD level. Patch 2 adds some code into hmm-tests.c which exercises the pagemap path for PMD device-private entries. This patch (of 2): pagemap_pmd_range_thp() warns if a non-present PMD is not a migration entry. This became false once device-private entries at the PMD level were added. Therefore, remove the stale migration-only assertion.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
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  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-72173

## 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/319caaca072adc564ac9c5357ed013909f23d5ab
- https://git.kernel.org/stable/c/cd1fc0e3c1f67c0c31dfc215e5d9b771133dedc0

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