Re: [PATCH 1/1] s390/dasd: Fix inconsistent kobject removal

[Cornelia Huck <cohuck@redhat.com>]

On Mon, 18 Jan 2021 17:55:18 +0100
Stefan Haberland <sth@linux.ibm.com> wrote:

> From: Jan Höppner <hoeppner@linux.ibm.com>
> 
> Our intention was to only remove path kobjects whenever a device is
> being set offline. However, one corner case was missing.
> 
> If a device is disabled and enabled (using the IOCTLs BIODASDDISABLE and
> BIODASDENABLE respectively), the enabling process will call
> dasd_eckd_reload_device() which itself calls dasd_eckd_read_conf() in
> order to update path information. During that update,
> dasd_eckd_clear_conf_data() clears all old data and also removes all
> kobjects. This will leave us with an inconsistent state of path kobjects
> and a subsequent path verification leads to a failing kobject creation.
> 
> Fix this by removing kobjects only in the context of offlining a device
> as initially intended.
> 
> Fixes: 19508b204740 ("s390/dasd: Display FC Endpoint Security information via sysfs")
> Reported-by: Stefan Haberland <sth@linux.ibm.com>
> Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
> Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
> ---
>  drivers/s390/block/dasd_devmap.c | 20 ++++++++++++++------
>  drivers/s390/block/dasd_eckd.c   |  3 ++-
>  drivers/s390/block/dasd_int.h    |  2 +-
>  3 files changed, 17 insertions(+), 8 deletions(-)

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