nvme: copy firmware_rev on each init

The firmware revision can change on after a reset so copy the most
recent info each time instead of just the first time, otherwise the
sysfs firmware_rev entry may contain stale data.
Reported-by: Jeff Lien <jeff.lien@wdc.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/host/core.c

@@ -2893,7 +2893,6 @@ static int nvme_init_subsystem(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id)
 	nvme_init_subnqn(subsys, ctrl, id);
 	memcpy(subsys->serial, id->sn, sizeof(subsys->serial));
 	memcpy(subsys->model, id->mn, sizeof(subsys->model));
-	memcpy(subsys->firmware_rev, id->fr, sizeof(subsys->firmware_rev));
 	subsys->vendor_id = le16_to_cpu(id->vid);
 	subsys->cmic = id->cmic;
 
@@ -3112,6 +3111,8 @@ static int nvme_init_identify(struct nvme_ctrl *ctrl)
 				ctrl->quirks |= core_quirks[i].quirks;
 		}
 	}
+	memcpy(ctrl->subsys->firmware_rev, id->fr,
+	       sizeof(ctrl->subsys->firmware_rev));
 
 	if (force_apst && (ctrl->quirks & NVME_QUIRK_NO_DEEPEST_PS)) {
 		dev_warn(ctrl->device, "forcibly allowing all power states due to nvme_core.force_apst -- use at your own risk\n");