[v4] make logical_block_size configurable

[PATCH v4 1/2] md: prevent adding disks with larger logical_block_size to active arrays

Posted by linan666@huaweicloud.com 3 weeks ago

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.

The later patch will introduce a way to configure the array's
logical_block_size.

The issue was introduced before Linux 2.6.12-rc2.

Fixes: d2e45eace8 ("[PATCH] Fix raid "bio too big" failures")
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 a77c59527d4c..40f56183c744 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);
-- 
2.39.2

Re: [PATCH v4 1/2] md: prevent adding disks with larger logical_block_size to active arrays

Posted by Xiao Ni 2 weeks, 6 days ago

On Thu, Sep 11, 2025 at 3:41 PM <linan666@huaweicloud.com> wrote:
>
> 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.
>
> The later patch will introduce a way to configure the array's
> logical_block_size.
>
> The issue was introduced before Linux 2.6.12-rc2.
>
> Fixes: d2e45eace8 ("[PATCH] Fix raid "bio too big" failures")

Hi Li Nan

I can't find the commit in
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

git show d2e45eace8
fatal: ambiguous argument 'd2e45eace8': unknown revision or path not
in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'

Regards
Xiao
> 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 a77c59527d4c..40f56183c744 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);
> --
> 2.39.2
>

Re: [PATCH v4 1/2] md: prevent adding disks with larger logical_block_size to active arrays

Posted by Li Nan 2 weeks, 6 days ago


在 2025/9/12 11:18, Xiao Ni 写道:
> On Thu, Sep 11, 2025 at 3:41 PM <linan666@huaweicloud.com> wrote:
>>
>> 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.
>>
>> The later patch will introduce a way to configure the array's
>> logical_block_size.
>>
>> The issue was introduced before Linux 2.6.12-rc2.
>>
>> Fixes: d2e45eace8 ("[PATCH] Fix raid "bio too big" failures")
> 
> Hi Li Nan
> 
> I can't find the commit in
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> 
> git show d2e45eace8
> fatal: ambiguous argument 'd2e45eace8': unknown revision or path not
> in the working tree.
> Use '--' to separate paths from revisions, like this:
> 'git <command> [<revision>...] -- [<file>...]'
> 
> Regards
> Xiao

Thank you for your reply.

As mentioned in the commit message, the issue was introduced before Linux
2.6.12-rc2, and needs to be get it in the history repository.

https://kernel.googlesource.com/pub/scm/linux/kernel/git/tglx/history.git

-- 
Thanks,
Nan