Re: [PATCH v3 1/2] md: prevent adding disks with larger logical_block_size to active arrays

[Paul Menzel <pmenzel@molgen.mpg.de>]

Dear Li,


Thank you for your patch.

Am 25.08.25 um 09:59 schrieb linan666@huaweicloud.com:
> From: Li Nan <linan122@huawei.com>
> 
> When adding a disk to a md array, avoid updating the array's
> logical_block_size to match the new disk. This prevents accidental
> partition table loss that renders the array unusable.

Do you have a reproducer to test this?

> The later patch will introduce a way to configure the array's
> logical_block_size.
> 
> Signed-off-by: Li Nan <linan122@huawei.com>
> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
> ---
>   drivers/md/md.c | 7 +++++++
>   1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/md/md.c b/drivers/md/md.c
> index cea8fc96abd3..206434591b97 100644
> --- a/drivers/md/md.c
> +++ b/drivers/md/md.c
> @@ -6064,6 +6064,13 @@ int mddev_stack_new_rdev(struct mddev *mddev, struct md_rdev *rdev)
>   	if (mddev_is_dm(mddev))
>   		return 0;
>   
> +	if (queue_logical_block_size(rdev->bdev->bd_disk->queue) >
> +	    queue_logical_block_size(mddev->gendisk->queue)) {
> +		pr_err("%s: incompatible logical_block_size, can not add\n",
> +		       mdname(mddev));
> +		return -EINVAL;
> +	}
> +
>   	lim = queue_limits_start_update(mddev->gendisk->queue);
>   	queue_limits_stack_bdev(&lim, rdev->bdev, rdev->data_offset,
>   				mddev->gendisk->disk_name);


Kind regards,

Paul