net: dst_cache: add two DEBUG_NET warnings

After fixing four different bugs involving dst_cache
users, it might be worth adding a check about BH being
blocked by dst_cache callers.

DEBUG_NET_WARN_ON_ONCE(!in_softirq());

It is not fatal, if we missed valid case where no
BH deadlock is to be feared, we might change this.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240531132636.2637995-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Eric Dumazet 2024-05-31 13:26:36 +00:00 committed by Jakub Kicinski
parent cf28ff8e4c
commit 2fe6fb36c7

View File

@ -27,6 +27,7 @@ struct dst_cache_pcpu {
static void dst_cache_per_cpu_dst_set(struct dst_cache_pcpu *dst_cache,
struct dst_entry *dst, u32 cookie)
{
DEBUG_NET_WARN_ON_ONCE(!in_softirq());
dst_release(dst_cache->dst);
if (dst)
dst_hold(dst);
@ -40,6 +41,7 @@ static struct dst_entry *dst_cache_per_cpu_get(struct dst_cache *dst_cache,
{
struct dst_entry *dst;
DEBUG_NET_WARN_ON_ONCE(!in_softirq());
dst = idst->dst;
if (!dst)
goto fail;