Steffen Trumtrar

**Name of the Vulnerable Software and Affected Versions** Linux kernel (affected versions not specified) **Description** The issue is related to the `qbman` component of the Linux kernel, where the `smp call function` always runs its callback in hard IRQ context, even on `PREEMPT RT`, where spinlocks can sleep. This requires the use of a raw spinlock for `cgr lock` to prevent waiting on a sleeping task. The bug was not apparent until commit `ef2a8d5478b9` ("net: dpaa: Adjust queue depth on rate change") which invokes `smp call function single` via `qman update cgr safe` every time a link goes up or down. **Recommendations** At the moment, there is no information about a newer version that contains a fix for this vulnerability.