i40e: Fix removing driver while bare-metal VFs pass traffic

Prevent VFs from resetting when PF driver is being unloaded:
- introduce new pf state: __I40E_VF_RESETS_DISABLED;
- check if pf state has __I40E_VF_RESETS_DISABLED state set,
  if so, disable any further VFLR event notifications;
- when i40e_remove (rmmod i40e) is called, disable any resets on
  the VFs;

Previously if there were bare-metal VFs passing traffic and PF
driver was removed, there was a possibility of VFs triggering a Tx
timeout right before iavf_remove. This was causing iavf_close to
not be called because there is a check in the beginning of  iavf_remove
that bails out early if adapter->state < IAVF_DOWN_PENDING. This
makes it so some resources do not get cleaned up.

Fixes: 6a9ddb36eeb8 ("i40e: disable IOV before freeing resources")
Signed-off-by: Slawomir Laba <slawomirx.laba@intel.com>
Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Signed-off-by: Sylwester Dziedziuch <sylwesterx.dziedziuch@intel.com>
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://lore.kernel.org/r/20201120180640.3654474-1-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index 537300e762f049b204a62609bf0facce676f0cfe..d231a2cdd98ff244acb0c796dea11c84767e1404 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -140,6 +140,7 @@ enum i40e_state_t {
        __I40E_CLIENT_RESET,
        __I40E_VIRTCHNL_OP_PENDING,
        __I40E_RECOVERY_MODE,
+       __I40E_VF_RESETS_DISABLED,      /* disable resets during i40e_remove */
        /* This must be last as it determines the size of the BITMAP */
        __I40E_STATE_SIZE__,
 };

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 4f8a2154b93fee621edc8ba356d8046412ca1558..1337686bd0998003e1a92a56f03ed7d8d8a99a3e 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -4010,8 +4010,16 @@ static irqreturn_t i40e_intr(int irq, void *data)
        }
 
        if (icr0 & I40E_PFINT_ICR0_VFLR_MASK) {
-               ena_mask &= ~I40E_PFINT_ICR0_ENA_VFLR_MASK;
-               set_bit(__I40E_VFLR_EVENT_PENDING, pf->state);
+               /* disable any further VFLR event notifications */
+               if (test_bit(__I40E_VF_RESETS_DISABLED, pf->state)) {
+                       u32 reg = rd32(hw, I40E_PFINT_ICR0_ENA);
+
+                       reg &= ~I40E_PFINT_ICR0_VFLR_MASK;
+                       wr32(hw, I40E_PFINT_ICR0_ENA, reg);
+               } else {
+                       ena_mask &= ~I40E_PFINT_ICR0_ENA_VFLR_MASK;
+                       set_bit(__I40E_VFLR_EVENT_PENDING, pf->state);
+               }
        }
 
        if (icr0 & I40E_PFINT_ICR0_GRST_MASK) {
@@ -15311,6 +15319,11 @@ static void i40e_remove(struct pci_dev *pdev)
        while (test_bit(__I40E_RESET_RECOVERY_PENDING, pf->state))
                usleep_range(1000, 2000);
 
+       if (pf->flags & I40E_FLAG_SRIOV_ENABLED) {
+               set_bit(__I40E_VF_RESETS_DISABLED, pf->state);
+               i40e_free_vfs(pf);
+               pf->flags &= ~I40E_FLAG_SRIOV_ENABLED;
+       }
        /* no more scheduling of any task */
        set_bit(__I40E_SUSPENDED, pf->state);
        set_bit(__I40E_DOWN, pf->state);
@@ -15337,11 +15350,6 @@ static void i40e_remove(struct pci_dev *pdev)
         */
        i40e_notify_client_of_netdev_close(pf->vsi[pf->lan_vsi], false);
 
-       if (pf->flags & I40E_FLAG_SRIOV_ENABLED) {
-               i40e_free_vfs(pf);
-               pf->flags &= ~I40E_FLAG_SRIOV_ENABLED;
-       }
-
        i40e_fdir_teardown(pf);
 
        /* If there is a switch structure or any orphans, remove them.

diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
index 4919d22d7b6bde5511ecd662f881c479ef9ee854..1b5390ec3d78a4e50b0a7c31c33b36669369d136 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
@@ -1403,7 +1403,8 @@ static void i40e_cleanup_reset_vf(struct i40e_vf *vf)
  * @vf: pointer to the VF structure
  * @flr: VFLR was issued or not
  *
- * Returns true if the VF is reset, false otherwise.
+ * Returns true if the VF is in reset, resets successfully, or resets
+ * are disabled and false otherwise.
  **/
 bool i40e_reset_vf(struct i40e_vf *vf, bool flr)
 {
@@ -1413,11 +1414,14 @@ bool i40e_reset_vf(struct i40e_vf *vf, bool flr)
        u32 reg;
        int i;
 
+       if (test_bit(__I40E_VF_RESETS_DISABLED, pf->state))
+               return true;
+
        /* If the VFs have been disabled, this means something else is
         * resetting the VF, so we shouldn't continue.
         */
        if (test_and_set_bit(__I40E_VF_DISABLE, pf->state))
-               return false;
+               return true;
 
        i40e_trigger_vf_reset(vf, flr);
 
@@ -1581,6 +1585,15 @@ void i40e_free_vfs(struct i40e_pf *pf)
 
        i40e_notify_client_of_vf_enable(pf, 0);
 
+       /* Disable IOV before freeing resources. This lets any VF drivers
+        * running in the host get themselves cleaned up before we yank
+        * the carpet out from underneath their feet.
+        */
+       if (!pci_vfs_assigned(pf->pdev))
+               pci_disable_sriov(pf->pdev);
+       else
+               dev_warn(&pf->pdev->dev, "VFs are assigned - not disabling SR-IOV\n");
+
        /* Amortize wait time by stopping all VFs at the same time */
        for (i = 0; i < pf->num_alloc_vfs; i++) {
                if (test_bit(I40E_VF_STATE_INIT, &pf->vf[i].vf_states))
@@ -1596,15 +1609,6 @@ void i40e_free_vfs(struct i40e_pf *pf)
                i40e_vsi_wait_queues_disabled(pf->vsi[pf->vf[i].lan_vsi_idx]);
        }
 
-       /* Disable IOV before freeing resources. This lets any VF drivers
-        * running in the host get themselves cleaned up before we yank
-        * the carpet out from underneath their feet.
-        */
-       if (!pci_vfs_assigned(pf->pdev))
-               pci_disable_sriov(pf->pdev);
-       else
-               dev_warn(&pf->pdev->dev, "VFs are assigned - not disabling SR-IOV\n");
-
        /* free up VF resources */
        tmp = pf->num_alloc_vfs;
        pf->num_alloc_vfs = 0;