1 files changed, 8 insertions, 1 deletions

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index e45b18ee04c3..f6b3e31f63cd 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -1164,7 +1164,7 @@ static inline void ahci_gtf_filter_workaround(struct ata_host *host)
 #endif
 
 static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
-                         struct ahci_host_priv *hpriv)
+                                struct ahci_host_priv *hpriv)
 {
         int nvec;
 
@@ -1189,6 +1189,13 @@ static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
         else if (nvec < 0)
                 goto intx;
 
+        /* fallback to single MSI mode if the controller enforced MRSM mode */
+        if (readl(hpriv->mmio + HOST_CTL) & HOST_MRSM) {
+                pci_disable_msi(pdev);
+                printk(KERN_INFO "ahci: MRSM is on, fallback to single MSI\n");
+                goto single_msi;
+        }
+
         return nvec;
 
 single_msi: