1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index c6c0434d8034..a75122d1c710 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -2580,7 +2580,8 @@ static int hpsa_passthru_ioctl(struct ctlr_info *h, void __user *argp)
                 c->SG[0].Ext = 0; /* we are not chaining*/
         }
         hpsa_scsi_do_simple_cmd_core(h, c);
-        hpsa_pci_unmap(h->pdev, c, 1, PCI_DMA_BIDIRECTIONAL);
+        if (iocommand.buf_size > 0)
+                hpsa_pci_unmap(h->pdev, c, 1, PCI_DMA_BIDIRECTIONAL);
         check_ioctl_unit_attention(h, c);
 
         /* Copy the error information out */