Re: [PATCH net-next 4/9] netconsole: move netpoll_local_ip_unset() as netcons_local_ip_unset()

Move netpoll_local_ip_unset() from netpoll to netconsole and rename it
to netcons_local_ip_unset();

The body is otherwise unchanged, only the comment's setup-function
reference is updated.

Signed-off-by: Breno Leitao <leitao@debian.org>
---
 drivers/net/netconsole.c | 19 ++++++++++++++++++-
 include/linux/netpoll.h  |  1 -
 net/core/netpoll.c       | 18 ------------------
 3 files changed, 18 insertions(+), 20 deletions(-)

diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
index 3a7a2cafc6276..70f9c5bfb3720 100644
--- a/drivers/net/netconsole.c
+++ b/drivers/net/netconsole.c

@@ -351,6 +351,23 @@ static void netconsole_skb_pool_flush(struct netconsole_target *nt)
        skb_queue_purge_reason(&nt->skb_pool, SKB_CONSUMED);
 }

+/*
+ * Test whether the caller left np->local_ip unset, so that
+ * netcons_netpoll_setup() should auto-populate it from the egress device.
+ *
+ * np->local_ip is a union of __be32 (IPv4) and struct in6_addr (IPv6),
+ * so an IPv6 address whose first 4 bytes are zero (e.g. ::1, ::2,
+ * IPv4-mapped ::ffff:a.b.c.d) must not be tested via the IPv4 arm —
+ * doing so would misclassify a caller-supplied address as unset and
+ * silently overwrite it with whatever address the device exposes.
+ */
+static bool netcons_local_ip_unset(const struct netpoll *np)
+{
+       if (np->ipv6)
+               return ipv6_addr_any(&np->local_ip.in6);
+       return !np->local_ip.ip;
+}