Re: [PATCH V4 7/9] nvme-core: align fabrics_q teardown with admin_q in nvme_free_ctrl

["Maurizio Lombardi" <mlombard@arkamax.eu>]

On Mon May 11, 2026 at 11:53 AM CEST, Hannes Reinecke wrote:
> On 5/8/26 15:33, Maurizio Lombardi wrote:
>> Currently, the final reference for the fabrics admin queue (fabrics_q)
>> is dropped inside nvme_remove_admin_tag_set(). However, the primary
>> admin queue (admin_q) defers dropping its final reference until
>> nvme_free_ctrl().
>> 
>> Move the blk_put_queue() call for fabrics_q from nvme_remove_admin_tag_set()
>> to nvme_free_ctrl(). This aligns the lifecycle management of both admin
>> queues, ensuring they are freed symmetrically when the controller is finally
>> torn down.
>> 
>> Reviewed-by: Daniel Wagner <dwagner@suse.de>
>> Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
>> ---
>>   drivers/nvme/host/core.c | 6 +++---
>>   1 file changed, 3 insertions(+), 3 deletions(-)
>> 
>> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
>> index 5d3200a66f8e..73575d087a07 100644
>> --- a/drivers/nvme/host/core.c
>> +++ b/drivers/nvme/host/core.c
>> @@ -4932,10 +4932,8 @@ void nvme_remove_admin_tag_set(struct nvme_ctrl *ctrl)
>>   	 */
>>   	nvme_stop_keep_alive(ctrl);
>>   	blk_mq_destroy_queue(ctrl->admin_q);
>> -	if (ctrl->ops->flags & NVME_F_FABRICS) {
>> +	if (ctrl->ops->flags & NVME_F_FABRICS)
>>   		blk_mq_destroy_queue(ctrl->fabrics_q);
>> -		blk_put_queue(ctrl->fabrics_q);
>> -	}
>>   	blk_mq_free_tag_set(ctrl->admin_tagset);
>>   }
>>   EXPORT_SYMBOL_GPL(nvme_remove_admin_tag_set);
>> @@ -5077,6 +5075,8 @@ static void nvme_free_ctrl(struct device *dev)
>>   
>>   	if (ctrl->admin_q)
>>   		blk_put_queue(ctrl->admin_q);
>> +	if (ctrl->fabrics_q)
>> +		blk_put_queue(ctrl->fabrics_q);
>>   	if (!subsys || ctrl->instance != subsys->instance)
>>   		ida_free(&nvme_instance_ida, ctrl->instance);
>>   	nvme_free_cels(ctrl);
>
> One wonders why we check for 'flags' in the first hunk, but for the 
> existence of 'fabrics_q' in the second hunk.
> But anyway.

That is true,

I have to send a V5 anyway to address other comments, so I will change it to use
if(ctrl->fabrics_q).

Maurizio