[PATCH 5.19 573/717] iavf: Fix race between iavf_close and iavf_reset_task

Greg Kroah-Hartman
2022-10-22T08:28:50Z

From: Michal Jaron <michalx.jaron@intel.com>

[ Upstream commit 11c12adcbc1598d91e73ab6ddfa41d25a01478ed ]

During stress tests with adding VF to namespace and changing vf's
trust there was a race between iavf_reset_task and iavf_close.
Sometimes when IAVF_FLAG_AQ_DISABLE_QUEUES from iavf_close was sent
to PF after reset and before IAVF_AQ_GET_CONFIG was sent then PF
returns error IAVF_NOT_SUPPORTED to disable queues request and
following requests. There is need to get_config before other
aq_required will be send but iavf_close clears all flags, if
get_config was not sent before iavf_close, then it will not be send
at all.

In case when IAVF_FLAG_AQ_GET_OFFLOAD_VLAN_V2_CAPS was sent before
IAVF_FLAG_AQ_DISABLE_QUEUES then there was rtnl_lock deadlock
between iavf_close and iavf_adminq_task until iavf_close timeouts
and disable queues was sent after iavf_close ends.

There was also a problem with sending delete/add filters.
Sometimes when filters was not yet added to PF and in
iavf_close all filters was set to remove there might be a try
to remove nonexistent filters on PF.

Add aq_required_tmp to save aq_required flags and send them after
disable_queues will be handled. Clear flags given to iavf_down
different than IAVF_FLAG_AQ_GET_CONFIG as this flag is necessary
to sent other aq_required. Remove some flags that we don't
want to send as we are in iavf_close and we want to disable
interface. Remove filters which was not yet sent and send del
filters flags only when there are filters to remove.

Signed-off-by: Michal Jaron <michalx.jaron@intel.com>
Signed-off-by: Mateusz Palczewski <mateusz.palczewski@intel.com>
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/intel/iavf/iavf_main.c | 177 ++++++++++++++++----
1 file changed, 141 insertions(+), 36 deletions(-)

diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index 981c43b204ff..d3822c264642 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -1184,66 +1184,138 @@ static void iavf_up_complete(struct iavf_adapter *adapter)
}

/**
- * iavf_down - Shutdown the connection processing
+ * iavf_clear_mac_vlan_filters - Remove mac and vlan filters not sent to PF
+ * yet and mark other to be removed.
* @adapter: board private structure
- *
- * Expects to be called while holding the __IAVF_IN_CRITICAL_TASK bit lock.
**/
-void iavf_down(struct iavf_adapter *adapter)
+static void iavf_clear_mac_vlan_filters(struct iavf_adapter *adapter)
{
- struct net_device *netdev = adapter->netdev;
- struct iavf_vlan_filter *vlf;
- struct iavf_cloud_filter *cf;
- struct iavf_fdir_fltr *fdir;
- struct iavf_mac_filter *f;
- struct iavf_adv_rss *rss;
-
- if (adapter->state <= __IAVF_DOWN_PENDING)
- return;
-
- netif_carrier_off(netdev);
- netif_tx_disable(netdev);
- adapter->link_up = false;
- iavf_napi_disable_all(adapter);
- iavf_irq_disable(adapter);
+ struct iavf_vlan_filter *vlf, *vlftmp;
+ struct iavf_mac_filter *f, *ftmp;

spin_lock_bh(&adapter->mac_vlan_list_lock);
-
/* clear the sync flag on all filters */
__dev_uc_unsync(adapter->netdev, NULL);
__dev_mc_unsync(adapter->netdev, NULL);

/* remove all MAC filters */
- list_for_each_entry(f, &adapter->mac_filter_list, list) {
- f->remove = true;
+ list_for_each_entry_safe(f, ftmp, &adapter->mac_filter_list,
+ list) {
+ if (f->add) {
+ list_del(&f->list);
+ kfree(f);
+ } else {
+ f->remove = true;
+ }
}

/* remove all VLAN filters */
- list_for_each_entry(vlf, &adapter->vlan_filter_list, list) {
- vlf->remove = true;
+ list_for_each_entry_safe(vlf, vlftmp, &adapter->vlan_filter_list,
+ list) {
+ if (vlf->add) {
+ list_del(&vlf->list);
+ kfree(vlf);
+ } else {
+ vlf->remove = true;
+ }
}
-
spin_unlock_bh(&adapter->mac_vlan_list_lock);
+}
+
+/**
+ * iavf_clear_cloud_filters - Remove cloud filters not sent to PF yet and
+ * mark other to be removed.
+ * @adapter: board private structure
+ **/
+static void iavf_clear_cloud_filters(struct iavf_adapter *adapter)
+{
+ struct iavf_cloud_filter *cf, *cftmp;

/* remove all cloud filters */
spin_lock_bh(&adapter->cloud_filter_list_lock);
- list_for_each_entry(cf, &adapter->cloud_filter_list, list) {
- cf->del = true;
+ list_for_each_entry_safe(cf, cftmp, &adapter->cloud_filter_list,
+ list) {
+ if (cf->add) {
+ list_del(&cf->list);
+ kfree(cf);
+ adapter->num_cloud_filters--;
+ } else {
+ cf->del = true;
+ }
}
spin_unlock_bh(&adapter->cloud_filter_list_lock);
+}
+
+/**
+ * iavf_clear_fdir_filters - Remove fdir filters not sent to PF yet and mark
+ * other to be removed.
+ * @adapter: board private structure
+ **/
+static void iavf_clear_fdir_filters(struct iavf_adapter *adapter)
+{
+ struct iavf_fdir_fltr *fdir, *fdirtmp;

/* remove all Flow Director filters */
spin_lock_bh(&adapter->fdir_fltr_lock);
- list_for_each_entry(fdir, &adapter->fdir_list_head, list) {
- fdir->state = IAVF_FDIR_FLTR_DEL_REQUEST;
+ list_for_each_entry_safe(fdir, fdirtmp, &adapter->fdir_list_head,
+ list) {
+ if (fdir->state == IAVF_FDIR_FLTR_ADD_REQUEST) {
+ list_del(&fdir->list);
+ kfree(fdir);
+ adapter->fdir_active_fltr--;
+ } else {
+ fdir->state = IAVF_FDIR_FLTR_DEL_REQUEST;
+ }
}
spin_unlock_bh(&adapter->fdir_fltr_lock);
+}
+
+/**
+ * iavf_clear_adv_rss_conf - Remove adv rss conf not sent to PF yet and mark
+ * other to be removed.
+ * @adapter: board private structure
+ **/
+static void iavf_clear_adv_rss_conf(struct iavf_adapter *adapter)
+{
+ struct iavf_adv_rss *rss, *rsstmp;

/* remove all advance RSS configuration */
spin_lock_bh(&adapter->adv_rss_lock);
- list_for_each_entry(rss, &adapter->adv_rss_list_head, list)
- rss->state = IAVF_ADV_RSS_DEL_REQUEST;
+ list_for_each_entry_safe(rss, rsstmp, &adapter->adv_rss_list_head,
+ list) {
+ if (rss->state == IAVF_ADV_RSS_ADD_REQUEST) {
+ list_del(&rss->list);
+ kfree(rss);
+ } else {
+ rss->state = IAVF_ADV_RSS_DEL_REQUEST;
+ }
+ }
spin_unlock_bh(&adapter->adv_rss_lock);
+}
+
+/**
+ * iavf_down - Shutdown the connection processing
+ * @adapter: board private structure
+ *
+ * Expects to be called while holding the __IAVF_IN_CRITICAL_TASK bit lock.
+ **/
+void iavf_down(struct iavf_adapter *adapter)
+{
+ struct net_device *netdev = adapter->netdev;
+
+ if (adapter->state <= __IAVF_DOWN_PENDING)
+ return;
+
+ netif_carrier_off(netdev);
+ netif_tx_disable(netdev);
+ adapter->link_up = false;
+ iavf_napi_disable_all(adapter);
+ iavf_irq_disable(adapter);
+
+ iavf_clear_mac_vlan_filters(adapter);
+ iavf_clear_cloud_filters(adapter);
+ iavf_clear_fdir_filters(adapter);
+ iavf_clear_adv_rss_conf(adapter);

if (!(adapter->flags & IAVF_FLAG_PF_COMMS_FAILED)) {
/* cancel any current operation */
@@ -1252,11 +1324,16 @@ void iavf_down(struct iavf_adapter *adapter)
* here for this to complete. The watchdog is still running
* and it will take care of this.
*/
- adapter->aq_required = IAVF_FLAG_AQ_DEL_MAC_FILTER;
- adapter->aq_required |= IAVF_FLAG_AQ_DEL_VLAN_FILTER;
- adapter->aq_required |= IAVF_FLAG_AQ_DEL_CLOUD_FILTER;
- adapter->aq_required |= IAVF_FLAG_AQ_DEL_FDIR_FILTER;
- adapter->aq_required |= IAVF_FLAG_AQ_DEL_ADV_RSS_CFG;
+ if (!list_empty(&adapter->mac_filter_list))
+ adapter->aq_required |= IAVF_FLAG_AQ_DEL_MAC_FILTER;
+ if (!list_empty(&adapter->vlan_filter_list))
+ adapter->aq_required |= IAVF_FLAG_AQ_DEL_VLAN_FILTER;
+ if (!list_empty(&adapter->cloud_filter_list))
+ adapter->aq_required |= IAVF_FLAG_AQ_DEL_CLOUD_FILTER;
+ if (!list_empty(&adapter->fdir_list_head))
+ adapter->aq_required |= IAVF_FLAG_AQ_DEL_FDIR_FILTER;
+ if (!list_empty(&adapter->adv_rss_list_head))
+ adapter->aq_required |= IAVF_FLAG_AQ_DEL_ADV_RSS_CFG;
adapter->aq_required |= IAVF_FLAG_AQ_DISABLE_QUEUES;
}

@@ -4082,6 +4159,7 @@ static int iavf_open(struct net_device *netdev)
static int iavf_close(struct net_device *netdev)
{
struct iavf_adapter *adapter = netdev_priv(netdev);
+ u64 aq_to_restore;
int status;

mutex_lock(&adapter->crit_lock);
@@ -4094,6 +4172,29 @@ static int iavf_close(struct net_device *netdev)
set_bit(__IAVF_VSI_DOWN, adapter->vsi.state);
if (CLIENT_ENABLED(adapter))
adapter->flags |= IAVF_FLAG_CLIENT_NEEDS_CLOSE;
+ /* We cannot send IAVF_FLAG_AQ_GET_OFFLOAD_VLAN_V2_CAPS before
+ * IAVF_FLAG_AQ_DISABLE_QUEUES because in such case there is rtnl
+ * deadlock with adminq_task() until iavf_close timeouts. We must send
+ * IAVF_FLAG_AQ_GET_CONFIG before IAVF_FLAG_AQ_DISABLE_QUEUES to make
+ * disable queues possible for vf. Give only necessary flags to
+ * iavf_down and save other to set them right before iavf_close()
+ * returns, when IAVF_FLAG_AQ_DISABLE_QUEUES will be already sent and
+ * iavf will be in DOWN state.
+ */
+ aq_to_restore = adapter->aq_required;
+ adapter->aq_required &= IAVF_FLAG_AQ_GET_CONFIG;
+
+ /* Remove flags which we do not want to send after close or we want to
+ * send before disable queues.
+ */
+ aq_to_restore &= ~(IAVF_FLAG_AQ_GET_CONFIG |
+ IAVF_FLAG_AQ_ENABLE_QUEUES |
+ IAVF_FLAG_AQ_CONFIGURE_QUEUES |
+ IAVF_FLAG_AQ_ADD_VLAN_FILTER |
+ IAVF_FLAG_AQ_ADD_MAC_FILTER |
+ IAVF_FLAG_AQ_ADD_CLOUD_FILTER |
+ IAVF_FLAG_AQ_ADD_FDIR_FILTER |
+ IAVF_FLAG_AQ_ADD_ADV_RSS_CFG);

iavf_down(adapter);
iavf_change_state(adapter, __IAVF_DOWN_PENDING);
@@ -4117,6 +4218,10 @@ static int iavf_close(struct net_device *netdev)
msecs_to_jiffies(500));
if (!status)
netdev_warn(netdev, "Device resources not yet released\n");
+
+ mutex_lock(&adapter->crit_lock);
+ adapter->aq_required |= aq_to_restore;
+ mutex_unlock(&adapter->crit_lock);
return 0;
}

--
2.35.1