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Date:   Wed,  1 Jun 2022 00:07:01 -0700
In-Reply-To: <20220601070707.3946847-1-saravanak@google.com>
Message-Id: <20220601070707.3946847-6-saravanak@google.com>
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Subject: [PATCH v2 5/9] net: ipconfig: Relax fw_devlink if we need to mount a
 network rootfs
From:   Saravana Kannan <saravanak@google.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Kevin Hilman <khilman@kernel.org>,
        Ulf Hansson <ulf.hansson@linaro.org>,
        Len Brown <len.brown@intel.com>, Pavel Machek <pavel@ucw.cz>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        Andrew Lunn <andrew@lunn.ch>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        David Ahern <dsahern@kernel.org>
Cc:     Saravana Kannan <saravanak@google.com>, kernel-team@android.com,
        linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
        iommu@lists.linux-foundation.org, netdev@vger.kernel.org,
        linux-gpio@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

If there are network devices that could probe without some of their
suppliers probing and those network devices are needed to mount a
network rootfs, then fw_devlink=on might break that usecase by blocking
the network devices from probing by the time IP auto config starts.

So, if no network devices are available when IP auto config is enabled
and we have a network rootfs, make sure fw_devlink doesn't block the
probing of any device that has a driver and then retry finding a network
device.

Signed-off-by: Saravana Kannan <saravanak@google.com>
---
 net/ipv4/ipconfig.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c
index 9d41d5d5cd1e..2342debd7066 100644
--- a/net/ipv4/ipconfig.c
+++ b/net/ipv4/ipconfig.c
@@ -1434,6 +1434,7 @@ __be32 __init root_nfs_parse_addr(char *name)
 static int __init wait_for_devices(void)
 {
 	int i;
+	bool try_init_devs = true;
 
 	for (i = 0; i < DEVICE_WAIT_MAX; i++) {
 		struct net_device *dev;
@@ -1452,6 +1453,11 @@ static int __init wait_for_devices(void)
 		rtnl_unlock();
 		if (found)
 			return 0;
+		if (try_init_devs &&
+		    (ROOT_DEV == Root_NFS || ROOT_DEV == Root_CIFS)) {
+			try_init_devs = false;
+			wait_for_init_devices_probe();
+		}
 		ssleep(1);
 	}
 	return -ENODEV;
-- 
2.36.1.255.ge46751e96f-goog