The kernel lacked a periodic cond_resched() call inside swap_reclaim_full_clusters, allowing the reclamation loop to run for extended periods without relinquishing control to the scheduler. This failure can result in a softlockup of a worker thread and, under sustained heavy memory and swap activity, the kernel eventually panics. The flaw is related to resource exhaustion and improper scheduling control, aligning with CWE-667 and CWE-770. The impact is a loss of availability for the affected system, while confidentiality and integrity remain unaffected.

The vulnerability is present in the Linux kernel’s mm/swap code, which exists on all architectures where swap_reclaim_full_clusters is compiled. The detailed stack trace references an arm64 environment with a 320‑CPU, 1 TB machine, implying that arm64 is a confirmed affected platform. Based on the code location, kernels that have not yet incorporated the patch that adds cond_resched() in this function are potentially affected; however, no explicit version range is given in the supplied data.

The EPSS score is reported as < 1 %, indicating a very low likelihood of exploitation, and the vulnerability is not listed in the CISA KEV catalog. Attackers would need to execute a local or privileged workload that triggers large‑scale swap reclamation under heavy memory pressure, which is unlikely in typical operational environments. The CVSS score is 5.5, suggesting moderate severity. Overall, the risk is moderate due to the availability impact but low exploitation probability, especially when normal workloads do not exercise the problematic path.