Re: [PATCH v2 07/10] s390/dasd: Fix operational path inconsistency

[Cornelia Huck <cohuck@redhat.com>]

On Thu,  8 Oct 2020 15:13:33 +0200
Stefan Haberland <sth@linux.ibm.com> wrote:

> From: Jan Höppner <hoeppner@linux.ibm.com>
> 
> During online processing and setting up a DASD device, the configuration
> data for operational paths is read and validated two times
> (dasd_eckd_read_conf()). The first time to provide information that are
> necessary for the LCU setup. A second time after the LCU setup as a
> device might report different configuration data then.
> 
> When the configuration setup for each operational path is being
> validated, an initial call to dasd_eckd_clear_conf_data() is issued.
> This call wipes all previously available configuration data and path
> information for each path.
> However, the operational path mask is not updated during this process.
> 
> As a result, the stored operational path mask might no longer correspond
> to the operational paths mask reported by the CIO layer, as several
> paths might be gone between the two dasd_eckd_read_conf() calls.
> 
> This inconsistency leads to more severe issues in later path handling
> changes. Fix this by removing the channel paths from the operational
> path mask during the dasd_eckd_clear_conf_data() call.
> 
> Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
> Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
> Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
> ---
>  drivers/s390/block/dasd_eckd.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
> index 3ff7b532a5bf..3273b26b25b0 100644
> --- a/drivers/s390/block/dasd_eckd.c
> +++ b/drivers/s390/block/dasd_eckd.c
> @@ -1034,6 +1034,7 @@ static void dasd_eckd_clear_conf_data(struct dasd_device *device)
>  		device->path[i].cssid = 0;
>  		device->path[i].ssid = 0;
>  		device->path[i].chpid = 0;
> +		dasd_path_notoper(device, i);
>  	}
>  }
>  

Reviewed-by: Cornelia Huck <cohuck@redhat.com>