lkml.org 
[lkml]   [2012]   [Aug]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[ 010/109] SCSI: libsas: fix sas_discover_devices return code handling
Date
From: Greg KH <gregkh@linuxfoundation.org>

3.4-stable review patch. If anyone has any objections, please let me know.

------------------

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

commit b17caa174a7e1fd2e17b26e210d4ee91c4c28b37 upstream.

commit 198439e4 [SCSI] libsas: do not set res = 0 in sas_ex_discover_dev()
commit 19252de6 [SCSI] libsas: fix wide port hotplug issues

The above commits seem to have confused the return value of
sas_ex_discover_dev which is non-zero on failure and
sas_ex_join_wide_port which just indicates short circuiting discovery on
already established ports. The result is random discovery failures
depending on configuration.

Calls to sas_ex_join_wide_port are the source of the trouble as its
return value is errantly assigned to 'res'. Convert it to bool and stop
returning its result up the stack.

Tested-by: Dan Melnic <dan.melnic@amd.com>
Reported-by: Dan Melnic <dan.melnic@amd.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/scsi/libsas/sas_expander.c | 39 +++++++++++--------------------------
1 file changed, 12 insertions(+), 27 deletions(-)

--- a/drivers/scsi/libsas/sas_expander.c
+++ b/drivers/scsi/libsas/sas_expander.c
@@ -868,7 +868,7 @@ static struct domain_device *sas_ex_disc
}

/* See if this phy is part of a wide port */
-static int sas_ex_join_wide_port(struct domain_device *parent, int phy_id)
+static bool sas_ex_join_wide_port(struct domain_device *parent, int phy_id)
{
struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
int i;
@@ -884,11 +884,11 @@ static int sas_ex_join_wide_port(struct
sas_port_add_phy(ephy->port, phy->phy);
phy->port = ephy->port;
phy->phy_state = PHY_DEVICE_DISCOVERED;
- return 0;
+ return true;
}
}

- return -ENODEV;
+ return false;
}

static struct domain_device *sas_ex_discover_expander(
@@ -1030,8 +1030,7 @@ static int sas_ex_discover_dev(struct do
return res;
}

- res = sas_ex_join_wide_port(dev, phy_id);
- if (!res) {
+ if (sas_ex_join_wide_port(dev, phy_id)) {
SAS_DPRINTK("Attaching ex phy%d to wide port %016llx\n",
phy_id, SAS_ADDR(ex_phy->attached_sas_addr));
return res;
@@ -1077,8 +1076,7 @@ static int sas_ex_discover_dev(struct do
if (SAS_ADDR(ex->ex_phy[i].attached_sas_addr) ==
SAS_ADDR(child->sas_addr)) {
ex->ex_phy[i].phy_state= PHY_DEVICE_DISCOVERED;
- res = sas_ex_join_wide_port(dev, i);
- if (!res)
+ if (sas_ex_join_wide_port(dev, i))
SAS_DPRINTK("Attaching ex phy%d to wide port %016llx\n",
i, SAS_ADDR(ex->ex_phy[i].attached_sas_addr));

@@ -1943,32 +1941,20 @@ static int sas_discover_new(struct domai
{
struct ex_phy *ex_phy = &dev->ex_dev.ex_phy[phy_id];
struct domain_device *child;
- bool found = false;
- int res, i;
+ int res;

SAS_DPRINTK("ex %016llx phy%d new device attached\n",
SAS_ADDR(dev->sas_addr), phy_id);
res = sas_ex_phy_discover(dev, phy_id);
if (res)
- goto out;
- /* to support the wide port inserted */
- for (i = 0; i < dev->ex_dev.num_phys; i++) {
- struct ex_phy *ex_phy_temp = &dev->ex_dev.ex_phy[i];
- if (i == phy_id)
- continue;
- if (SAS_ADDR(ex_phy_temp->attached_sas_addr) ==
- SAS_ADDR(ex_phy->attached_sas_addr)) {
- found = true;
- break;
- }
- }
- if (found) {
- sas_ex_join_wide_port(dev, phy_id);
+ return res;
+
+ if (sas_ex_join_wide_port(dev, phy_id))
return 0;
- }
+
res = sas_ex_discover_devices(dev, phy_id);
- if (!res)
- goto out;
+ if (res)
+ return res;
list_for_each_entry(child, &dev->ex_dev.children, siblings) {
if (SAS_ADDR(child->sas_addr) ==
SAS_ADDR(ex_phy->attached_sas_addr)) {
@@ -1978,7 +1964,6 @@ static int sas_discover_new(struct domai
break;
}
}
-out:
return res;
}




\
 
 \ /
  Last update: 2012-08-08 02:21    [W:0.405 / U:5.736 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site