Re: [PATCH] scsi: mpi3mr: Replace one-element arrays with flexible-array members

[Christophe JAILLET <christophe.jaillet@wanadoo.fr>]

Le 05/09/2025 à 03:43, Pedro Demarchi Gomes a écrit :
> One-element arrays are deprecated, and we are replacing them with flexible
> array members instead. So, replace one-element arrays with flexible-array
> members in multiple structures.
> 
> Signed-off-by: Pedro Demarchi Gomes <pedrodemargomes@gmail.com>
> ---
>   include/uapi/scsi/scsi_bsg_mpi3mr.h | 10 +++++-----
>   1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/include/uapi/scsi/scsi_bsg_mpi3mr.h b/include/uapi/scsi/scsi_bsg_mpi3mr.h
> index f5ea1db92339..9e5b6ced53ab 100644
> --- a/include/uapi/scsi/scsi_bsg_mpi3mr.h
> +++ b/include/uapi/scsi/scsi_bsg_mpi3mr.h
> @@ -205,7 +205,7 @@ struct mpi3mr_all_tgt_info {
>   	__u16	num_devices;
>   	__u16	rsvd1;
>   	__u32	rsvd2;
> -	struct mpi3mr_device_map_info dmi[1];
> +	struct mpi3mr_device_map_info dmi[];
>   };
>   
>   /**
> @@ -248,7 +248,7 @@ struct mpi3mr_logdata_entry {
>   	__u8	valid_entry;
>   	__u8	rsvd1;
>   	__u16	rsvd2;
> -	__u8	data[1]; /* Variable length Array */
> +	__u8	data[]; /* Variable length Array */
>   };
>   
>   /**
> @@ -259,7 +259,7 @@ struct mpi3mr_logdata_entry {
>    * @entry: Variable length Log data entry array
>    */
>   struct mpi3mr_bsg_in_log_data {
> -	struct mpi3mr_logdata_entry entry[1];
> +	__DECLARE_FLEX_ARRAY(struct mpi3mr_logdata_entry, entry);
>   };
>   
>   /**
> @@ -307,7 +307,7 @@ struct mpi3mr_bsg_in_hdb_status {
>   	__u8    element_trigger_format;
>   	__u16	rsvd2;
>   	__u32	rsvd3;
> -	struct mpi3mr_hdb_entry entry[1];
> +	struct mpi3mr_hdb_entry entry[];

I think that the -1 at [1] should be removed, and struct_size() used 
instead.

The same kind of issue is maybe also relevant for the other changes, but 
I've not spotted such places myself.

CJ

[1]: 
https://elixir.bootlin.com/linux/v6.17-rc4/source/drivers/scsi/mpi3mr/mpi3mr_app.c#L1245

>   };
>   
>   /**
> @@ -416,7 +416,7 @@ struct mpi3mr_buf_entry_list {
>   	__u8	rsvd1;
>   	__u16	rsvd2;
>   	__u32	rsvd3;
> -	struct mpi3mr_buf_entry buf_entry[1];
> +	struct mpi3mr_buf_entry buf_entry[];
>   };
>   /**
>    * struct mpi3mr_bsg_mptcmd -  Generic bsg data