On Fri, 2018-03-09 at 13:59 +0100, Maurizio Lombardi wrote:
> diff --git a/drivers/block/paride/pcd.c b/drivers/block/paride/pcd.c
> index 7b8c636..a026211 100644
> --- a/drivers/block/paride/pcd.c
> +++ b/drivers/block/paride/pcd.c
> @@ -230,6 +230,8 @@ static int pcd_block_open(struct block_device *bdev, fmode_t mode)
> struct pcd_unit *cd = bdev->bd_disk->private_data;
> int ret;
>
> + check_disk_change(bdev);
> +
> mutex_lock(&pcd_mutex);
> ret = cdrom_open(&cd->info, bdev, mode);
> mutex_unlock(&pcd_mutex);
> diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
> index e36d160..8327478 100644
> --- a/drivers/cdrom/cdrom.c
> +++ b/drivers/cdrom/cdrom.c
> @@ -1152,9 +1152,6 @@ int cdrom_open(struct cdrom_device_info *cdi, struct block_device *bdev,
>
> cd_dbg(CD_OPEN, "entering cdrom_open\n");
>
> - /* open is event synchronization point, check events first */
> - check_disk_change(bdev);
> -
> /* if this was a O_NONBLOCK open and we should honor the flags,
> * do a quick open without drive/disc integrity checks. */
> cdi->use_count++;
> diff --git a/drivers/cdrom/gdrom.c b/drivers/cdrom/gdrom.c
> index 6495b03f..ae3a753 100644
> --- a/drivers/cdrom/gdrom.c
> +++ b/drivers/cdrom/gdrom.c
> @@ -497,6 +497,9 @@ static int gdrom_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd,
> static int gdrom_bdops_open(struct block_device *bdev, fmode_t mode)
> {
> int ret;
> +
> + check_disk_change(bdev);
> +
> mutex_lock(&gdrom_mutex);
> ret = cdrom_open(gd.cd_info, bdev, mode);
> mutex_unlock(&gdrom_mutex);
I think there is a much more elegant solution, namely splitting cdrom_mutex
into two synchronization objects - one that protects 'cdrom_list' changes
and another one that protects cdrom_sysctl_settings.info changes. Had you
considered that alternative?
Thanks,
Bart.
