Re: [PATCH AUTOSEL 5.16 203/217] net: dsa: hold rtnl_mutex when calling dsa_master_{setup,teardown}
From: Sasha Levin <sashal@kernel.org>
Date: 2022-01-22 19:17:47
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On Tue, Jan 18, 2022 at 02:13:29PM +0200, Vladimir Oltean wrote:
Hi Sasha, On Mon, Jan 17, 2022 at 09:19:26PM -0500, Sasha Levin wrote:quoted
From: Vladimir Oltean <vladimir.oltean@nxp.com> [ Upstream commit c146f9bc195a9dc3ad7fd000a14540e7c9df952d ] DSA needs to simulate master tracking events when a binding is first with a DSA master established and torn down, in order to give drivers the simplifying guarantee that ->master_state_change calls are made only when the master's readiness state to pass traffic changes. master_state_change() provide a operational bool that DSA driver can use to understand if DSA master is operational or not. To avoid races, we need to block the reception of NETDEV_UP/NETDEV_CHANGE/NETDEV_GOING_DOWN events in the netdev notifier chain while we are changing the master's dev->dsa_ptr (this changes what netdev_uses_dsa(dev) reports). The dsa_master_setup() and dsa_master_teardown() functions optionally require the rtnl_mutex to be held, if the tagger needs the master to be promiscuous, these functions call dev_set_promiscuity(). Move the rtnl_lock() from that function and make it top-level. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> ---Please drop this patch from all stable branches (5.16, 5.15, 5.10). Thanks.
Dropped, thanks! -- Thanks, Sasha