linux-stable/drivers/scsi/fcoe
Neil Horman f9184df3b9 fcoe: close race on link speed detection in fcoe code
When creating an fcoe interfce, we call fcoe_link_speed_update before we add the
lports fcoe interface to the fc_hostlist.  Since network device events like
NETDEV_CHANGE are only processed if an fcoe interface is found with an
underlying netdev that matches the netdev of the event.  Since this processing
in fcoe_device_notification is how link_speed changes get communicated to the
libfc  code (via fcoe_link_speed_update), we have a race condition - if a
NETDEV_CHANGE event is sent after the call to fcoe_link_speed_update in
fcoe_netdev_config, but before we add the interface to the fc_hostlist, we will
loose the event and attributes like /sys/class/fc_host/hostX/speed will not get
updated properly.

Fix this by moving the add to the fc_hostlist above the serialized call to
fcoe_netdev_config, ensuring that we catch netdev envents before we make a
direct call to fcoe_link_speed_update.

Also use this opportunity to clean up access to the fc_hostlist a bit by
creating a fcoe_hostlist_del accessor and replacing the cleanup in fcoe_exit to
use it properly.

Tested by myself successfully

[ Comment over 80 chars broken into multi-line by Robert Love to
  satisfy checkpatch.pl ]

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Reviewed-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
2013-01-28 11:13:01 -08:00
..
fcoe.c fcoe: close race on link speed detection in fcoe code 2013-01-28 11:13:01 -08:00
fcoe.h libfc, libfcoe, fcoe: Convert debug_logging macros to pr_info 2012-12-14 10:38:55 -08:00
fcoe_ctlr.c fcoe: Use the fcoe_sysfs control interface 2012-12-14 10:38:54 -08:00
fcoe_sysfs.c libfcoe, fcoe, bnx2fc: Add new fcoe control interface 2012-12-14 10:38:54 -08:00
fcoe_transport.c debris left by "[SCSI] libfcoe: Remove mutex_trylock/restart_syscall checks" 2012-12-14 10:38:56 -08:00
libfcoe.h libfc, libfcoe, fcoe: Convert debug_logging macros to pr_info 2012-12-14 10:38:55 -08:00
Makefile [SCSI] libfcoe: Add fcoe_sysfs 2012-05-23 09:40:09 +01:00