[PATCH 1 of 3] MD RAID10: Prep for DM RAID10 device replacement capability

[PATCH 1 of 3] MD RAID10: Prep for DM RAID10 device replacement capability

[Jonathan Brassow]

MD RAID10:  Fix a couple potential kernel panics if RAID10 is used by dm-raid

When device-mapper uses the RAID10 personality through dm-raid.c, there is no
'gendisk' structure in mddev and some sysfs information is also not populated.

This patch avoids touching those non-existent structures.

Signed-off-by: Jonathan Brassow <jbrassow@rehdat.com>

Index: linux-upstream/drivers/md/md.c
===================================================================
--- linux-upstream.orig/drivers/md/md.c
+++ linux-upstream/drivers/md/md.c
@@ -2056,8 +2056,14 @@ EXPORT_SYMBOL(md_integrity_register);
 /* Disable data integrity if non-capable/non-matching disk is being added */
 void md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev)
 {
-	struct blk_integrity *bi_rdev = bdev_get_integrity(rdev->bdev);
-	struct blk_integrity *bi_mddev = blk_get_integrity(mddev->gendisk);
+	struct blk_integrity *bi_rdev;
+	struct blk_integrity *bi_mddev;
+
+	if (!mddev->gendisk)
+		return;
+
+	bi_rdev = bdev_get_integrity(rdev->bdev);
+	bi_mddev = blk_get_integrity(mddev->gendisk);
 
 	if (!bi_mddev) /* nothing to do */
 		return;
Index: linux-upstream/drivers/md/raid10.c
===================================================================
--- linux-upstream.orig/drivers/md/raid10.c
+++ linux-upstream/drivers/md/raid10.c
@@ -1632,7 +1632,7 @@ static int raid10_spare_active(struct md
 			   && !test_bit(Faulty, &tmp->rdev->flags)
 			   && !test_and_set_bit(In_sync, &tmp->rdev->flags)) {
 			count++;
-			sysfs_notify_dirent(tmp->rdev->sysfs_state);
+			sysfs_notify_dirent_safe(tmp->rdev->sysfs_state);
 		}
 	}
 	spin_lock_irqsave(&conf->device_lock, flags);

Re: [PATCH 1 of 3] MD RAID10: Prep for DM RAID10 device replacement capability

[NeilBrown]

[-- Attachment #1: Type: text/plain, Size: 2242 bytes --]

On Fri, 24 Aug 2012 13:18:35 -0500 Jonathan Brassow <jbrassow@redhat.com>
wrote:

> MD RAID10:  Fix a couple potential kernel panics if RAID10 is used by dm-raid
> 
> When device-mapper uses the RAID10 personality through dm-raid.c, there is no
> 'gendisk' structure in mddev and some sysfs information is also not populated.
> 
> This patch avoids touching those non-existent structures.
> 
> Signed-off-by: Jonathan Brassow <jbrassow@rehdat.com>
> 
> Index: linux-upstream/drivers/md/md.c
> ===================================================================
> --- linux-upstream.orig/drivers/md/md.c
> +++ linux-upstream/drivers/md/md.c
> @@ -2056,8 +2056,14 @@ EXPORT_SYMBOL(md_integrity_register);
>  /* Disable data integrity if non-capable/non-matching disk is being added */
>  void md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev)
>  {
> -	struct blk_integrity *bi_rdev = bdev_get_integrity(rdev->bdev);
> -	struct blk_integrity *bi_mddev = blk_get_integrity(mddev->gendisk);
> +	struct blk_integrity *bi_rdev;
> +	struct blk_integrity *bi_mddev;
> +
> +	if (!mddev->gendisk)
> +		return;
> +
> +	bi_rdev = bdev_get_integrity(rdev->bdev);
> +	bi_mddev = blk_get_integrity(mddev->gendisk);
>  
>  	if (!bi_mddev) /* nothing to do */
>  		return;
> Index: linux-upstream/drivers/md/raid10.c
> ===================================================================
> --- linux-upstream.orig/drivers/md/raid10.c
> +++ linux-upstream/drivers/md/raid10.c
> @@ -1632,7 +1632,7 @@ static int raid10_spare_active(struct md
>  			   && !test_bit(Faulty, &tmp->rdev->flags)
>  			   && !test_and_set_bit(In_sync, &tmp->rdev->flags)) {
>  			count++;
> -			sysfs_notify_dirent(tmp->rdev->sysfs_state);
> +			sysfs_notify_dirent_safe(tmp->rdev->sysfs_state);
>  		}
>  	}
>  	spin_lock_irqsave(&conf->device_lock, flags);
> 


This and the other too all look fine - applied.  Thanks.

While reviewing I noticed:

			if (value > rs->md.raid_disks) {
				rs->ti->error = "Invalid rebuild index given";
				return -EINVAL;
			}

(in the 'rebuild' handling).  That should be  'value >= rs->md.raid_disks'
shouldn't it?
If you agree, please send a patch.

Thanks,
NeilBrown

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 828 bytes --]

Re: [PATCH 1 of 3] MD RAID10: Prep for DM RAID10 device replacement capability

[Brassow Jonathan]

On Sep 4, 2012, at 9:03 PM, NeilBrown wrote:

> While reviewing I noticed:
> 
> 			if (value > rs->md.raid_disks) {
> 				rs->ti->error = "Invalid rebuild index given";
> 				return -EINVAL;
> 			}
> 
> (in the 'rebuild' handling).  That should be  'value >= rs->md.raid_disks'
> shouldn't it?
> If you agree, please send a patch.

Yes.  Thank-you for catching that.  Patch coming shortly.

 brassow