| Message ID | 20201112144948.3042-1-vee.khee.wong@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [net,1/1] net: stmmac: Use rtnl_lock/unlock on netif_set_real_num_rx_queues() call | expand |
On Thu, 12 Nov 2020 22:49:48 +0800 Wong Vee Khee wrote: > Fix an issue where dump stack is printed on suspend resume flow due to > netif_set_real_num_rx_queues() is not called with rtnl_lock held(). > > Fixes: 686cff3d7022 ("net: stmmac: Fix incorrect location to set real_num_rx|tx_queues") > Reported-by: Christophe ROULLIER <christophe.roullier@st.com> > Tested-by: Christophe ROULLIER <christophe.roullier@st.com> > Cc: Alexandre TORGUE <alexandre.torgue@st.com> > Reviewed-by: Ong Boon Leong <boon.leong.ong@intel.com> > Signed-off-by: Wong Vee Khee <vee.khee.wong@intel.com> > --- > drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > index ba855465a2db..33e280040000 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > @@ -5278,7 +5278,10 @@ int stmmac_resume(struct device *dev) > > stmmac_clear_descriptors(priv); > > + rtnl_lock(); > stmmac_hw_setup(ndev, false); > + rtnl_unlock(); > + > stmmac_init_coalesce(priv); > stmmac_set_rx_mode(ndev); > Doesn't look quite right. This is under the priv->lock which is sometimes taken under rtnl_lock. So theoretically there could be a deadlock. You should probably take rtnl_lock() before priv->lock and release it after. It's pretty common for drivers to hold rtnl_lock around most of the resume method. With larger context: mutex_lock(&priv->lock); stmmac_reset_queues_param(priv); stmmac_clear_descriptors(priv); + rtnl_lock(); stmmac_hw_setup(ndev, false); + rtnl_unlock(); + stmmac_init_coalesce(priv); stmmac_set_rx_mode(ndev); stmmac_restore_hw_vlan_rx_fltr(priv, ndev, priv->hw); stmmac_enable_all_queues(priv); mutex_unlock(&priv->lock);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index ba855465a2db..33e280040000 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -5278,7 +5278,10 @@ int stmmac_resume(struct device *dev) stmmac_clear_descriptors(priv); + rtnl_lock(); stmmac_hw_setup(ndev, false); + rtnl_unlock(); + stmmac_init_coalesce(priv); stmmac_set_rx_mode(ndev);
Fix an issue where dump stack is printed on suspend resume flow due to netif_set_real_num_rx_queues() is not called with rtnl_lock held(). Fixes: 686cff3d7022 ("net: stmmac: Fix incorrect location to set real_num_rx|tx_queues") Reported-by: Christophe ROULLIER <christophe.roullier@st.com> Tested-by: Christophe ROULLIER <christophe.roullier@st.com> Cc: Alexandre TORGUE <alexandre.torgue@st.com> Reviewed-by: Ong Boon Leong <boon.leong.ong@intel.com> Signed-off-by: Wong Vee Khee <vee.khee.wong@intel.com> --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 3 +++ 1 file changed, 3 insertions(+)