On Monday 2010-05-31 15:13, Eric Dumazet wrote:

All cpus share a single cache line for their 'stackptr' storage,
introduced in commit f3c5c1bfd4

This is a stable candidate (2.6.34)

Stackptr was first introduced for 2.6.35-rcX.

+	i->stackptr = alloc_percpu(unsigned int);
	if (i->stackptr == NULL)
		return -ENOMEM;
-	memset(i->stackptr, 0, size);

	size = sizeof(void **) * nr_cpu_ids;
	if (size > PAGE_SIZE)

Are alloc_percpu areas cleared?

Acked-By: Jan Engelhardt <redacted>