[PATCH] nvme: verify MNAN value if ANA is enabled

[PATCH] nvme: verify MNAN value if ANA is enabled

[Daniel Wagner]

The controller is required to have a non-zero MNAN value if it supports
ANA:

   If the controller supports Asymmetric Namespace Access Reporting, then
   this field shall be set to a non-zero value that is less than or equal
   to the NN value.

Signed-off-by: Daniel Wagner <dwagner@suse.de>
---
This is a follow up to the discussion in

  https://lore.kernel.org/linux-nvme/20210521144734.90044-1-dwagner@suse.de/

 drivers/nvme/host/core.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index cb1a76a3d42a..4c412adc9e14 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -2972,6 +2972,16 @@ static int nvme_init_identify(struct nvme_ctrl *ctrl)
 	if (ret < 0)
 		goto out_free;
 
+#ifdef CONFIG_NVME_MULTIPATH
+	if (ctrl->ana_log_buf && (!ctrl->max_namespaces ||
+				  ctrl->max_namespaces > le32_to_cpu(id->nn))) {
+		dev_err(ctrl->device,
+			"Invalid MNAN value %u\n", ctrl->max_namespaces);
+		ret = -EINVAL;
+		goto out_free;
+	}
+#endif
+
 	if (ctrl->apst_enabled && !prev_apst_enabled)
 		dev_pm_qos_expose_latency_tolerance(ctrl->device);
 	else if (!ctrl->apst_enabled && prev_apst_enabled)
-- 
2.29.2

Re: [PATCH] nvme: verify MNAN value if ANA is enabled

[Hannes Reinecke]

On 5/31/21 12:36 PM, Daniel Wagner wrote:
> The controller is required to have a non-zero MNAN value if it supports
> ANA:
> 
>    If the controller supports Asymmetric Namespace Access Reporting, then
>    this field shall be set to a non-zero value that is less than or equal
>    to the NN value.
> 
> Signed-off-by: Daniel Wagner <dwagner@suse.de>
> ---
> This is a follow up to the discussion in
> 
>   https://lore.kernel.org/linux-nvme/20210521144734.90044-1-dwagner@suse.de/
> 
>  drivers/nvme/host/core.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index cb1a76a3d42a..4c412adc9e14 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -2972,6 +2972,16 @@ static int nvme_init_identify(struct nvme_ctrl *ctrl)
>  	if (ret < 0)
>  		goto out_free;
>  
> +#ifdef CONFIG_NVME_MULTIPATH
> +	if (ctrl->ana_log_buf && (!ctrl->max_namespaces ||
> +				  ctrl->max_namespaces > le32_to_cpu(id->nn))) {
> +		dev_err(ctrl->device,
> +			"Invalid MNAN value %u\n", ctrl->max_namespaces);
> +		ret = -EINVAL;
> +		goto out_free;
> +	}
> +#endif
> +
>  	if (ctrl->apst_enabled && !prev_apst_enabled)
>  		dev_pm_qos_expose_latency_tolerance(ctrl->device);
>  	else if (!ctrl->apst_enabled && prev_apst_enabled)
> 
Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		        Kernel Storage Architect
hare@suse.de			               +49 911 74053 688
SUSE Software Solutions Germany GmbH, 90409 Nürnberg
GF: F. Imendörffer, HRB 36809 (AG Nürnberg)

Re: [PATCH] nvme: verify MNAN value if ANA is enabled

[Chaitanya Kulkarni]

On 5/31/21 03:43, Daniel Wagner wrote:
> The controller is required to have a non-zero MNAN value if it supports
> ANA:
>
>    If the controller supports Asymmetric Namespace Access Reporting, then
>    this field shall be set to a non-zero value that is less than or equal
>    to the NN value.
>
> Signed-off-by: Daniel Wagner <dwagner@suse.de>


Looks good.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

Re: [PATCH] nvme: verify MNAN value if ANA is enabled

[Christoph Hellwig]

> @@ -2972,6 +2972,16 @@ static int nvme_init_identify(struct nvme_ctrl *ctrl)
>  	if (ret < 0)
>  		goto out_free;
>  
> +#ifdef CONFIG_NVME_MULTIPATH
> +	if (ctrl->ana_log_buf && (!ctrl->max_namespaces ||
> +				  ctrl->max_namespaces > le32_to_cpu(id->nn))) {
> +		dev_err(ctrl->device,
> +			"Invalid MNAN value %u\n", ctrl->max_namespaces);
> +		ret = -EINVAL;
> +		goto out_free;
> +	}
> +#endif

Please move the check into nvme_mpath_init_identify, where we can avoid
the ifdef and the ana_log_buf check, which won't trigger for the first
initialization.