In the Linux kernel, the following vulnerability has been resolved:
powerpc/32: Fix hardlockup on vmap stack overflow
Since the commit c118c7303ad5 ("powerpc/32: Fix vmap stack - Do not
activate MMU before reading task struct") a vmap stack overflow
results in a hard lockup. This is because emergency_ctx is still
addressed with its virtual address allthough data MMU is not active
anymore at that time.
