1 files changed, 20 insertions, 4 deletions

diff --git a/drivers/net/sfc/efx.c b/drivers/net/sfc/efx.c
index b8bd936374f2..a3c2aab53de8 100644
--- a/drivers/net/sfc/efx.c
+++ b/drivers/net/sfc/efx.c
@@ -328,7 +328,8 @@ static int efx_poll(struct napi_struct *napi, int budget)
  * processing to finish, then directly poll (and ack ) the eventq.
  * Finally reenable NAPI and interrupts.
  *
- * Since we are touching interrupts the caller should hold the suspend lock
+ * This is for use only during a loopback self-test.  It must not
+ * deliver any packets up the stack as this can result in deadlock.
  */
 void efx_process_channel_now(struct efx_channel *channel)
 {
@@ -336,6 +337,7 @@ void efx_process_channel_now(struct efx_channel *channel)
 
         BUG_ON(channel->channel >= efx->n_channels);
         BUG_ON(!channel->enabled);
+        BUG_ON(!efx->loopback_selftest);
 
         /* Disable interrupts and wait for ISRs to complete */
         efx_nic_disable_interrupts(efx);
@@ -1054,6 +1056,7 @@ static int efx_init_io(struct efx_nic *efx)
 {
         struct pci_dev *pci_dev = efx->pci_dev;
         dma_addr_t dma_mask = efx->type->max_dma_mask;
+        bool use_wc;
         int rc;
 
         netif_dbg(efx, probe, efx->net_dev, "initialising I/O\n");
@@ -1104,8 +1107,21 @@ static int efx_init_io(struct efx_nic *efx)
                 rc = -EIO;
                 goto fail3;
         }
-        efx->membase = ioremap_wc(efx->membase_phys,
-                                  efx->type->mem_map_size);
+
+        /* bug22643: If SR-IOV is enabled then tx push over a write combined
+         * mapping is unsafe. We need to disable write combining in this case.
+         * MSI is unsupported when SR-IOV is enabled, and the firmware will
+         * have removed the MSI capability. So write combining is safe if
+         * there is an MSI capability.
+         */
+        use_wc = (!EFX_WORKAROUND_22643(efx) ||
+                  pci_find_capability(pci_dev, PCI_CAP_ID_MSI));
+        if (use_wc)
+                efx->membase = ioremap_wc(efx->membase_phys,
+                                          efx->type->mem_map_size);
+        else
+                efx->membase = ioremap_nocache(efx->membase_phys,
+                                               efx->type->mem_map_size);
         if (!efx->membase) {
                 netif_err(efx, probe, efx->net_dev,
                           "could not map memory BAR at %llx+%x\n",
@@ -1422,7 +1438,7 @@ static void efx_start_all(struct efx_nic *efx)
          * restart the transmit interface early so the watchdog timer stops */
         efx_start_port(efx);
 
-        if (efx_dev_registered(efx))
+        if (efx_dev_registered(efx) && !efx->port_inhibited)
                 netif_tx_wake_all_queues(efx->net_dev);
 
         efx_for_each_channel(channel, efx)