Re: [PATCH] libnvdimm/region: Fix label activation vs errors

[Jeff Moyer <jmoyer@redhat.com>]

Dan Williams <dan.j.williams@intel.com> writes:

> There are a few scenarios where init_active_labels() can return without
> registering deactivate_labels() to run when the region is disabled. In
> particular label error injection creates scenarios where a DIMM is
> disabled, but labels on other DIMMs in the region become activated.
>
> Arrange for init_active_labels() to always register deactivate_labels().
>
> Reported-by: Krzysztof Kensicki <krzysztof.kensicki@intel.com>
> Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation.")
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Reviewed-by: Jeff Moyer <jmoyer@redhat.com>


> ---
>  drivers/nvdimm/namespace_devs.c |   17 +++++++++++------
>  1 file changed, 11 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
> index 2403b71b601e..745478213ff2 100644
> --- a/drivers/nvdimm/namespace_devs.c
> +++ b/drivers/nvdimm/namespace_devs.c
> @@ -2527,7 +2527,7 @@ static void deactivate_labels(void *region)
>  
>  static int init_active_labels(struct nd_region *nd_region)
>  {
> -	int i;
> +	int i, rc = 0;
>  
>  	for (i = 0; i < nd_region->ndr_mappings; i++) {
>  		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
> @@ -2546,13 +2546,14 @@ static int init_active_labels(struct nd_region *nd_region)
>  			else if (test_bit(NDD_LABELING, &nvdimm->flags))
>  				/* fail, labels needed to disambiguate dpa */;
>  			else
> -				return 0;
> +				continue;
>  
>  			dev_err(&nd_region->dev, "%s: is %s, failing probe\n",
>  					dev_name(&nd_mapping->nvdimm->dev),
>  					test_bit(NDD_LOCKED, &nvdimm->flags)
>  					? "locked" : "disabled");
> -			return -ENXIO;
> +			rc = -ENXIO;
> +			goto out;
>  		}
>  		nd_mapping->ndd = ndd;
>  		atomic_inc(&nvdimm->busy);
> @@ -2586,13 +2587,17 @@ static int init_active_labels(struct nd_region *nd_region)
>  			break;
>  	}
>  
> -	if (i < nd_region->ndr_mappings) {
> +	if (i < nd_region->ndr_mappings)
> +		rc = -ENOMEM;
> +
> +out:
> +	if (rc) {
>  		deactivate_labels(nd_region);
> -		return -ENOMEM;
> +		return rc;
>  	}
>  
>  	return devm_add_action_or_reset(&nd_region->dev, deactivate_labels,
> -			nd_region);
> +					nd_region);
>  }
>  
>  int nd_region_register_namespaces(struct nd_region *nd_region, int *err)