Moger, Babu 3569e5374d [SCSI] scsi_dh_rdac: Fix for unbalanced reference count ... This patch fixes an unbalanced refcount issue. Elevating the lock for both kref_put and also for controller node deletion. Previously, controller deletion was protected but the not the kref_put. This was causing the other thread to pick up the controller structure which was already kref'd zero. This was causing the following WARN_ON and also sometimes panic. WARNING: at lib/kref.c:43 kref_get+0x2d/0x30() (Not tainted) Hardware name: IBM System x3655 -[7985AC1]- Modules linked in: fuse scsi_dh_rdac autofs4 nfs lockd fscache nfs_acl auth_rpcgss sunrpc 8021q garp stp llc ipv6 ib_srp(U) scsi_transport_srp scsi_tgt ib_cm(U) ib_sa(U) ib_uverbs(U) ib_umad(U) mlx4_ib(U) mlx4_core(U) ib_mthca(U) ib_mad(U) ib_core(U) dm_mirror dm_region_hash dm_log dm_round_robin dm_multipath uinput bnx2 ses enclosure sg ibmpex ibmaem ipmi_msghandler serio_raw k8temp hwmon amd64_edac_mod edac_core edac_mce_amd shpchp i2c_piix4 ext4 mbcache jbd2 sr_mod cdrom sd_mod crc_t10dif sata_svw pata_acpi ata_generic pata_serverworks aacraid radeon ttm drm_kms_helper drm i2c_algo_bit i2c_core dm_mod [last unloaded: freq_table] Pid: 13735, comm: srp_daemon Not tainted 2.6.32-71.el6.x86_64 #1 Call Trace: [<ffffffff8106b857>] warn_slowpath_common+0x87/0xc0 [<ffffffff8106b8aa>] warn_slowpath_null+0x1a/0x20 [<ffffffff8125c39d>] kref_get+0x2d/0x30 [<ffffffffa01b4029>] rdac_bus_attach+0x459/0x580 [scsi_dh_rdac] [<ffffffff8135232a>] scsi_dh_handler_attach+0x2a/0x80 [<ffffffff81352c7b>] scsi_dh_notifier+0x9b/0xa0 [<ffffffff814cd7a5>] notifier_call_chain+0x55/0x80 [<ffffffff8109711a>] __blocking_notifier_call_chain+0x5a/0x80 [<ffffffff81097156>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff8132bec5>] device_add+0x515/0x640 [<ffffffff813329e4>] ? attribute_container_device_trigger+0xc4/0xe0 [<ffffffff8134f659>] scsi_sysfs_add_sdev+0x89/0x2c0 [<ffffffff8134d096>] scsi_probe_and_add_lun+0xea6/0xed0 [<ffffffff8134beb2>] ? scsi_alloc_target+0x292/0x2d0 [<ffffffff8134d1e1>] __scsi_scan_target+0x121/0x750 [<ffffffff811df806>] ? sysfs_create_file+0x26/0x30 [<ffffffff8132b759>] ? device_create_file+0x19/0x20 [<ffffffff81332838>] ? attribute_container_add_attrs+0x78/0x90 [<ffffffff814b008c>] ? klist_next+0x4c/0xf0 [<ffffffff81332e30>] ? transport_configure+0x0/0x20 [<ffffffff813329e4>] ? attribute_container_device_trigger+0xc4/0xe0 [<ffffffff8134df40>] scsi_scan_target+0xd0/0xe0 [<ffffffffa02f053a>] srp_create_target+0x75a/0x890 [ib_srp] [<ffffffff8132a130>] dev_attr_store+0x20/0x30 [<ffffffff811df145>] sysfs_write_file+0xe5/0x170 [<ffffffff8116c818>] vfs_write+0xb8/0x1a0 [<ffffffff810d40a2>] ? audit_syscall_entry+0x272/0x2a0 [<ffffffff8116d251>] sys_write+0x51/0x90 [<ffffffff81013172>] system_call_fastpath+0x16/0x1b Signed-off-by: Babu Moger <babu.moger@netapp.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>		2012-02-22 12:15:19 -06:00
..
Kconfig	[SCSI] scsi_dh: add generic SPC-3 alua handler	2008-07-26 15:14:52 -04:00
Makefile	[SCSI] scsi_dh: add generic SPC-3 alua handler	2008-07-26 15:14:52 -04:00
scsi_dh_alua.c	[SCSI] scsi_dh_alua: Retry the check-condition in case Mode Parameters Changed	2012-01-10 17:01:24 -06:00
scsi_dh_emc.c	[SCSI] scsi_dh_emc: Add a match function for emc device handler	2011-12-15 10:55:00 +04:00
scsi_dh_hp_sw.c	[SCSI] scsi_dh_hp_sw: Adding the match function for hp_sw device handler	2011-12-15 10:55:00 +04:00
scsi_dh_rdac.c	[SCSI] scsi_dh_rdac: Fix for unbalanced reference count	2012-02-22 12:15:19 -06:00
scsi_dh.c	[SCSI] scsi_dh: code cleanup and remove the references to scsi_dev_info	2011-12-15 10:55:00 +04:00