From: wang di <di.wang@intel.com>
Date: Sun, 26 Jul 2015 14:42:36 +0000 (-0700)
Subject: LU-6916 target: fix ted_lcd_lock init
X-Git-Tag: 2.7.58~41
X-Git-Url: https://git.whamcloud.com/?a=commitdiff_plain;h=96a352c9ddeafe139097762211c7f64086016717;p=fs%2Flustre-release.git

LU-6916 target: fix ted_lcd_lock init

Move ted_lcd_lock init from tgt_client_new()
to tgt_client_alloc(), otherwise if error happens
in client_new_export(), the error handler path
will cause panic like this

<1>BUG: unable to handle kernel NULL pointer dereference at (null)
<1>IP: [<ffffffff812957f6>] __list_add+0x26/0xa0
<4> [<ffffffff8152adef>] __mutex_lock_slowpath+0xcf/0x180
<4> [<ffffffffa047e087>] ? cfs_hash_putref+0x2e7/0x480 [libcfs]
<4> [<ffffffff8152acfb>] mutex_lock+0x2b/0x50
<4> [<ffffffffa083db72>] tgt_client_free+0x62/0x610 [ptlrpc]
<4> [<ffffffffa0f59f84>] mdt_destroy_export+0x74/0x220 [mdt]
<4> [<ffffffffa05862c5>] class_new_export+0x315/0x9c0 [obdclass]
<4> [<ffffffffa058745e>] class_connect+0xae/0x250 [obdclass]
<4> [<ffffffffa0f57fd1>] mdt_obd_connect+0xb1/0x720 [mdt]
<4> [<ffffffffa07aaf78>] target_handle_connect+0xe58/0x2d30 [ptlrpc]
<4> [<ffffffff8128c1f0>] ? string+0x40/0x100
<4> [<ffffffffa084edf2>] tgt_request_handle+0x5b2/0x1230 [ptlrpc]
<4> [<ffffffffa07f7611>] ptlrpc_main+0xe41/0x1920 [ptlrpc]
<4> [<ffffffffa07f67d0>] ? ptlrpc_main+0x0/0x1920 [ptlrpc]
<4> [<ffffffff8109abf6>] kthread+0x96/0xa0
<4> [<ffffffff8100c20a>] child_rip+0xa/0x20
<4> [<ffffffff8109ab60>] ? kthread+0x0/0xa0
<4> [<ffffffff8100c200>] ? child_rip+0x0/0x20

Signed-off-by: wang di <di.wang@intel.com>
Change-Id: If09c019384f53a63107aeaa293ef93d6415f81b5
Reviewed-on: http://review.whamcloud.com/15770
Tested-by: Jenkins
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: Mike Pershin <mike.pershin@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
---

diff --git a/lustre/target/tgt_lastrcvd.c b/lustre/target/tgt_lastrcvd.c
index 558ee6b..4b5041a 100644
--- a/lustre/target/tgt_lastrcvd.c
+++ b/lustre/target/tgt_lastrcvd.c
@@ -383,6 +383,7 @@ int tgt_client_alloc(struct obd_export *exp)
 	/* Mark that slot is not yet valid, 0 doesn't work here */
 	exp->exp_target_data.ted_lr_idx = -1;
 	INIT_LIST_HEAD(&exp->exp_target_data.ted_reply_list);
+	mutex_init(&exp->exp_target_data.ted_lcd_lock);
 	RETURN(0);
 }
 EXPORT_SYMBOL(tgt_client_alloc);
@@ -886,8 +887,6 @@ int tgt_client_new(const struct lu_env *env, struct obd_export *exp)
 	if (!strcmp(ted->ted_lcd->lcd_uuid, tgt->lut_obd->obd_uuid.uuid))
 		RETURN(0);
 
-	mutex_init(&ted->ted_lcd_lock);
-
 	if (exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT)
 		RETURN(0);