A system bus error during a PDMA send operation can result in bytes being
lost. Theoretically that could cause the target to remain in DATA OUT
phase and the initiator (expecting a phase change) would time-out waiting
for the Last Byte Sent flag. Should that happen, fail the transfer so the
core driver will stop using PDMA with this target.

Cc: Michael Schmitz <schmitz...@gmail.com>
Tested-by: Stan Johnson <user...@yahoo.com>
Signed-off-by: Finn Thain <fth...@telegraphics.com.au>
---
 drivers/scsi/mac_scsi.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/mac_scsi.c b/drivers/scsi/mac_scsi.c
index 8fbec1768bbf..658a719cfcba 100644
--- a/drivers/scsi/mac_scsi.c
+++ b/drivers/scsi/mac_scsi.c
@@ -360,9 +360,12 @@ static inline int macscsi_pwrite(struct NCR5380_hostdata 
*hostdata,
                if (hostdata->pdma_residual == 0) {
                        if (NCR5380_poll_politely(hostdata, TARGET_COMMAND_REG,
                                                  TCR_LAST_BYTE_SENT,
-                                                 TCR_LAST_BYTE_SENT, HZ / 64) 
< 0)
+                                                 TCR_LAST_BYTE_SENT,
+                                                 HZ / 64) < 0) {
                                scmd_printk(KERN_ERR, hostdata->connected,
                                            "%s: Last Byte Sent timeout\n", 
__func__);
+                               result = -1;
+                       }
                        goto out;
                }
 
-- 
2.21.0

Reply via email to