From: Bart Van Assche <bart.vanassche@wdc.com>
Date: Fri, 23 Feb 2018 14:09:25 -0800
Subject: Revert "IB/srp: Avoid that a cable pull can trigger a kernel crash"
Patch-mainline: v4.17-rc1
Git-commit: c74ff7501e8dda9e9542a1fcabb2233776c1d19d
References: bsc#1103992 FATE#326009

The caller of srp_ib_lookup_path() is responsible for holding a reference
on the SCSI host. That means that commit 8a0d18c62121 was not necessary.
Hence revert it.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/ulp/srp/ib_srp.c |   25 ++++++-------------------
 1 file changed, 6 insertions(+), 19 deletions(-)

--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -765,19 +765,12 @@ static void srp_path_rec_completion(int
 static int srp_ib_lookup_path(struct srp_rdma_ch *ch)
 {
 	struct srp_target_port *target = ch->target;
-	int ret = -ENODEV;
+	int ret;
 
 	ch->ib_cm.path.numb_path = 1;
 
 	init_completion(&ch->done);
 
-	/*
-	 * Avoid that the SCSI host can be removed by srp_remove_target()
-	 * before srp_path_rec_completion() is called.
-	 */
-	if (!scsi_host_get(target->scsi_host))
-		goto out;
-
 	ch->ib_cm.path_query_id = ib_sa_path_rec_get(&srp_sa_client,
 					       target->srp_host->srp_dev->dev,
 					       target->srp_host->port,
@@ -791,27 +784,21 @@ static int srp_ib_lookup_path(struct srp
 					       GFP_KERNEL,
 					       srp_path_rec_completion,
 					       ch, &ch->ib_cm.path_query);
-	ret = ch->ib_cm.path_query_id;
-	if (ret < 0)
-		goto put;
+	if (ch->ib_cm.path_query_id < 0)
+		return ch->ib_cm.path_query_id;
 
 	ret = wait_for_completion_interruptible(&ch->done);
 	if (ret < 0)
-		goto put;
+		return ret;
 
-	ret = ch->status;
-	if (ret < 0)
+	if (ch->status < 0)
 		shost_printk(KERN_WARNING, target->scsi_host,
 			     PFX "Path record query failed: sgid %pI6, dgid %pI6, pkey %#04x, service_id %#16llx\n",
 			     ch->ib_cm.path.sgid.raw, ch->ib_cm.path.dgid.raw,
 			     be16_to_cpu(target->ib_cm.pkey),
 			     be64_to_cpu(target->ib_cm.service_id));
 
-put:
-	scsi_host_put(target->scsi_host);
-
-out:
-	return ret;
+	return ch->status;
 }
 
 static int srp_rdma_lookup_path(struct srp_rdma_ch *ch)