Re: [PATCH v3 09/18] nvmet-fcloop: prevent double port deletion

[Hannes Reinecke <hare@suse.de>]

On 3/18/25 11:40, Daniel Wagner wrote:
> The delete callback can be called either via the unregister function or
> from the transport directly. Thus it is necessary ensure resources are
> not freed multiple times.
> 
> Signed-off-by: Daniel Wagner <wagi@kernel.org>
> ---
>   drivers/nvme/target/fcloop.c | 18 ++++++++++++++++++
>   1 file changed, 18 insertions(+)
> 
> diff --git a/drivers/nvme/target/fcloop.c b/drivers/nvme/target/fcloop.c
> index de23f0bc5599b6f8dd5c3713dd38c952e6fdda28..06f42da6a0335c53ae319133119d057aab12e07e 100644
> --- a/drivers/nvme/target/fcloop.c
> +++ b/drivers/nvme/target/fcloop.c
> @@ -215,6 +215,8 @@ struct fcloop_lport_priv {
>   	struct fcloop_lport *lport;
>   };
>   
> +#define PORT_DELETE	0
> +
>   struct fcloop_rport {
>   	struct nvme_fc_remote_port	*remoteport;
>   	struct nvmet_fc_target_port	*targetport;
> @@ -223,6 +225,7 @@ struct fcloop_rport {
>   	spinlock_t			lock;
>   	struct list_head		ls_list;
>   	struct work_struct		ls_work;
> +	unsigned long			flags;
>   };
>   
>   struct fcloop_tport {
> @@ -233,6 +236,7 @@ struct fcloop_tport {
>   	spinlock_t			lock;
>   	struct list_head		ls_list;
>   	struct work_struct		ls_work;
> +	unsigned long			flags;
>   };
>   
>   struct fcloop_nport {
> @@ -1062,14 +1066,20 @@ static void
>   fcloop_remoteport_delete(struct nvme_fc_remote_port *remoteport)
>   {
>   	struct fcloop_rport *rport = remoteport->private;
> +	bool delete_port = true;
>   	unsigned long flags;
>   
>   	flush_work(&rport->ls_work);
>   
>   	spin_lock_irqsave(&fcloop_lock, flags);
> +	if (test_and_set_bit(PORT_DELETE, &rport->flags))
> +		delete_port = false;
>   	rport->nport->rport = NULL;
>   	spin_unlock_irqrestore(&fcloop_lock, flags);
>   
Can't you just check for a NULL rport->nport->rport pointer
and do away with the PORT_DELETE flag?

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
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