4.14-stable review patch. If anyone has any objections, please let me know.
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From: Tyrel Datwyler tyreld@linux.vnet.ibm.com
commit 7205981e045e752ccf96cf6ddd703a98c59d4339 upstream.
For each ibmvscsi host created during a probe or destroyed during a remove we either add or remove that host to/from the global ibmvscsi_head list. This runs the risk of concurrent modification.
This patch adds a simple spinlock around the list modification calls to prevent concurrent updates as is done similarly in the ibmvfc driver and ipr driver.
Fixes: 32d6e4b6e4ea ("scsi: ibmvscsi: add vscsi hosts to global list_head") Cc: stable@vger.kernel.org # v4.10+ Signed-off-by: Tyrel Datwyler tyreld@linux.vnet.ibm.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/scsi/ibmvscsi/ibmvscsi.c | 5 +++++ 1 file changed, 5 insertions(+)
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c @@ -96,6 +96,7 @@ static int client_reserve = 1; static char partition_name[96] = "UNKNOWN"; static unsigned int partition_number = -1; static LIST_HEAD(ibmvscsi_head); +static DEFINE_SPINLOCK(ibmvscsi_driver_lock);
static struct scsi_transport_template *ibmvscsi_transport_template;
@@ -2274,7 +2275,9 @@ static int ibmvscsi_probe(struct vio_dev }
dev_set_drvdata(&vdev->dev, hostdata); + spin_lock(&ibmvscsi_driver_lock); list_add_tail(&hostdata->host_list, &ibmvscsi_head); + spin_unlock(&ibmvscsi_driver_lock); return 0;
add_srp_port_failed: @@ -2296,7 +2299,9 @@ static int ibmvscsi_probe(struct vio_dev static int ibmvscsi_remove(struct vio_dev *vdev) { struct ibmvscsi_host_data *hostdata = dev_get_drvdata(&vdev->dev); + spin_lock(&ibmvscsi_driver_lock); list_del(&hostdata->host_list); + spin_unlock(&ibmvscsi_driver_lock); unmap_persist_bufs(hostdata); release_event_pool(&hostdata->pool, hostdata); ibmvscsi_release_crq_queue(&hostdata->queue, hostdata,