From d43c65b05b848e0b2db1a6c78b02c189da3a95b5 Mon Sep 17 00:00:00 2001
From: Heiner Kallweit <hkallweit1@gmail.com>
Date: Sun, 1 Aug 2021 12:41:31 +0200
Subject: [PATCH] ethtool: runtime-resume netdev parent in ethnl_ops_begin
If a network device is runtime-suspended then:
- network device may be flagged as detached and all ethtool ops (even if not
accessing the device) will fail because netif_device_present() returns
false
- ethtool ops may fail because device is not accessible (e.g. because being
in D3 in case of a PCI device)
It may not be desirable that userspace can't use even simple ethtool ops
that not access the device if interface or link is down. To be more friendly
to userspace let's ensure that device is runtime-resumed when executing the
respective ethtool op in kernel.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/ethtool/netlink.c | 31 +++++++++++++++++++++++++------
1 file changed, 25 insertions(+), 6 deletions(-)
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index e628d17f595c..417aaf9ca219 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -2,6 +2,7 @@
#include <net/sock.h>
#include <linux/ethtool_netlink.h>
+#include <linux/pm_runtime.h>
#include "netlink.h"
static struct genl_family ethtool_genl_family;
@@ -31,22 +32,40 @@ const struct nla_policy ethnl_header_policy_stats[] = {
int ethnl_ops_begin(struct net_device *dev)
{
+ int ret;
+
if (!dev)
return 0;
- if (!netif_device_present(dev))
- return -ENODEV;
+ if (dev->dev.parent)
+ pm_runtime_get_sync(dev->dev.parent);
- if (dev->ethtool_ops->begin)
- return dev->ethtool_ops->begin(dev);
- else
- return 0;
+ if (!netif_device_present(dev)) {
+ ret = -ENODEV;
+ goto err;
+ }
+
+ if (dev->ethtool_ops->begin) {
+ ret = dev->ethtool_ops->begin(dev);
+ if (ret)
+ goto err;
+ }
+
+ return 0;
+err:
+ if (dev->dev.parent)
+ pm_runtime_put(dev->dev.parent);
+
+ return ret;
}
void ethnl_ops_complete(struct net_device *dev)
{
if (dev && dev->ethtool_ops->complete)
dev->ethtool_ops->complete(dev);
+
+ if (dev->dev.parent)
+ pm_runtime_put(dev->dev.parent);
}
/**