Commit 6c996e19 authored Mar 25, 2021 by Dmitry Vyukov Committed by David S. Miller Mar 25, 2021

net: change netdev_unregister_timeout_secs min value to 1



netdev_unregister_timeout_secs=0 can lead to printing the
"waiting for dev to become free" message every jiffy.
This is too frequent and unnecessary.
Set the min value to 1 second.

Also fix the merge issue introduced by
"net: make unregister netdev warning timeout configurable":
it changed "refcnt != 1" to "refcnt".

Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Fixes: 5aa3afe1 ("net: make unregister netdev warning timeout configurable")
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent b01483a8

Documentation/admin-guide/sysctl/net.rst

+1 −1

Original line number	Diff line number	Diff line
		@@ -320,7 +320,7 @@ waiting for a network device refcount to drop to 0 during device
		unregistration. A lower value may be useful during bisection to detect
		a leaked reference faster. A larger value may be useful to prevent false
		warnings on slow/loaded systems.
		Default value is 10, minimum 0, maximum 3600.
		Default value is 10, minimum 1, maximum 3600.

		optmem_max
		----------

net/core/dev.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -10460,7 +10460,7 @@ static void netdev_wait_allrefs(struct net_device *dev)

		refcnt = netdev_refcnt_read(dev);

		if (refcnt &&
		if (refcnt != 1 &&
		time_after(jiffies, warning_time +
		netdev_unregister_timeout_secs * HZ)) {
		pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",

net/core/sysctl_net_core.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -577,7 +577,7 @@ static struct ctl_table net_core_table[] = {
		.maxlen = sizeof(unsigned int),
		.mode = 0644,
		.proc_handler = proc_dointvec_minmax,
		.extra1 = SYSCTL_ZERO,
		.extra1 = SYSCTL_ONE,
		.extra2 = &int_3600,
		},
		{ }