[ 128/167] [PATCH] [SCSI] libsas: fix false positive device attached conditions

Ben Hutchings
2012-05-09T06:16:56Z

From: Dan Williams <dan.j.williams@intel.com>

commit 7d1d865181185bdf1316d236b1b4bd02c9020729 upstream.

Normalize phy->attached_sas_addr to return a zero-address in the case
when device-type == NO_DEVICE or the linkrate is invalid to handle
expanders that put non-zero sas addresses in the discovery response:

sas: ex 5001b4da000f903f phy02:U:0 attached: 0100000000000000 (no device)
sas: ex 5001b4da000f903f phy01:U:0 attached: 0100000000000000 (no device)
sas: ex 5001b4da000f903f phy03:U:0 attached: 0100000000000000 (no device)
sas: ex 5001b4da000f903f phy00:U:0 attached: 0100000000000000 (no device)

Reported-by: Andrzej Jakowski <andrzej.jakowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/scsi/libsas/sas_expander.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/libsas/sas_expander.c b/drivers/scsi/libsas/sas_expander.c
index 75247a1..caa0525 100644
--- a/drivers/scsi/libsas/sas_expander.c
+++ b/drivers/scsi/libsas/sas_expander.c
@@ -245,7 +245,14 @@ static void sas_set_ex_phy(struct domain_device *dev, int phy_id, void *rsp)
phy->attached_sata_ps = dr->attached_sata_ps;
phy->attached_iproto = dr->iproto << 1;
phy->attached_tproto = dr->tproto << 1;
- memcpy(phy->attached_sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE);
+ /* help some expanders that fail to zero sas_address in the 'no
+ * device' case
+ */
+ if (phy->attached_dev_type == NO_DEVICE ||
+ phy->linkrate < SAS_LINK_RATE_1_5_GBPS)
+ memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
+ else
+ memcpy(phy->attached_sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE);
phy->attached_phy_id = dr->attached_phy_id;
phy->phy_change_count = dr->change_count;
phy->routing_attr = dr->routing_attr;
--
1.7.10