libnvdimm: btt_devs: Fix locking in namespace_store
Always take device_lock() before nvdimm_bus_lock() to prevent deadlock.
Cc: <stable@vger.kernel.org>
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/btt_devs.c b/drivers/nvdimm/btt_devs.c
index 59ad54a6..cb47751 100644
--- a/drivers/nvdimm/btt_devs.c
+++ b/drivers/nvdimm/btt_devs.c
@@ -128,13 +128,13 @@
struct nd_btt *nd_btt = to_nd_btt(dev);
ssize_t rc;
- nvdimm_bus_lock(dev);
device_lock(dev);
+ nvdimm_bus_lock(dev);
rc = nd_namespace_store(dev, &nd_btt->ndns, buf, len);
dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__,
rc, buf, buf[len - 1] == '\n' ? "" : "\n");
- device_unlock(dev);
nvdimm_bus_unlock(dev);
+ device_unlock(dev);
return rc;
}