The Linux kernel's real-time task migration aggressively pulls high-priority RT tasks from other CPUs to reduce latency. To address latency issues in PREEMPT_RT kernels, the RT_PUSH_IPI mechanism was introduced, which uses IPIs to coordinate task pushing instead of locking runqueues directly. However, in non-PREEMPT_RT kernels, where softirqs run in interrupt context, RT_PUSH_IPI can cause live locks by repeatedly sending IPIs that delay scheduling due to softirq execution. This results in CPUs being considered overloaded indefinitely, causing a scheduling live lock under heavy networking workloads on large multi-CPU systems. The vulnerability is fixed by disabling RT_PUSH_IPI by default on non-PREEMPT_RT kernels.

The vulnerability can cause live lock conditions on CPUs in non-PREEMPT_RT Linux kernels under heavy networking traffic and real-time task loads. This live lock prevents CPUs from scheduling tasks efficiently, leading to degraded system responsiveness and potential performance degradation in real-time and networking workloads. There is no indication of direct security compromise or privilege escalation, but system stability and performance can be severely impacted.

A fix is available that disables the RT_PUSH_IPI mechanism by default on non-PREEMPT_RT kernels, resolving the live lock issue. Users should update their Linux kernel to a version including this fix. Since this is a kernel-level fix, applying the official kernel update from the vendor or distribution is the recommended remediation. Patch status is not explicitly confirmed in the provided data; users should consult their Linux distribution or kernel vendor advisory for the exact fixed versions and update instructions.