[PATCH md 000 of 2] Introduction

[PATCH md 000 of 2] Introduction

[NeilBrown]

Two patches for md in 2.6.14-rc5-mm1 (First one depends on -mm stuff,
second should apply to most recent 2.6 kernels).

I'd like to review the sysfs a bit more before it goes to Linus, but
the rest can go anytime.
Thanks,
NeilBrown


 [PATCH md 001 of 2] Remove attempt to use dynamic names in sysfs for component devices on an MD array.
 [PATCH md 002 of 2] Allow md arrays to be started read-only (module parameter).

[PATCH md 001 of 2] Remove attempt to use dynamic names in sysfs for component devices on an MD array.

[NeilBrown]

With version-0.90 superblock, component devices on an md device to not have any
stable name related to the array -(version-1 assigns a fixed index when a
device is added to an array, and this remains despit any hot-swap).

The intial code for making these devices appear in sysfs used
dynamic names, which would change whenever a hot-spare was swapped
for a failed or missing device.
This turns out not to be practical in sysfs for a number of reasons.

This patch changes then naming of component devices to be based on
the result of 'bdevname'.  This is stable and should be unique.

Signed-off-by: Neil Brown <neilb@suse.de>

### Diffstat output
 ./drivers/md/md.c |   40 ++++++----------------------------------
 1 file changed, 6 insertions(+), 34 deletions(-)

diff ./drivers/md/md.c~current~ ./drivers/md/md.c
--- ./drivers/md/md.c~current~	2005-10-31 15:48:07.000000000 +1100
+++ ./drivers/md/md.c	2005-10-31 15:54:59.000000000 +1100
@@ -762,7 +762,7 @@ static void super_90_sync(mddev_t *mddev
 	struct list_head *tmp;
 	mdk_rdev_t *rdev2;
 	int next_spare = mddev->raid_disks;
-	char nm[20];
+
 
 	/* make rdev->sb match mddev data..
 	 *
@@ -776,7 +776,6 @@ static void super_90_sync(mddev_t *mddev
 	 */
 	int i;
 	int active=0, working=0,failed=0,spare=0,nr_disks=0;
-	unsigned int fixdesc=0;
 
 	rdev->sb_size = MD_SB_BYTES;
 
@@ -830,16 +829,7 @@ static void super_90_sync(mddev_t *mddev
 			desc_nr = rdev2->raid_disk;
 		else
 			desc_nr = next_spare++;
-		if (desc_nr != rdev2->desc_nr) {
-			fixdesc |= (1 << desc_nr);
-			rdev2->desc_nr = desc_nr;
-			if (rdev2->raid_disk >= 0) {
-				sprintf(nm, "rd%d", rdev2->raid_disk);
-				sysfs_remove_link(&mddev->kobj, nm);
-			}
-			sysfs_remove_link(&rdev2->kobj, "block");
-			kobject_del(&rdev2->kobj);
-		}
+		rdev2->desc_nr = desc_nr;
 		d = &sb->disks[rdev2->desc_nr];
 		nr_disks++;
 		d->number = rdev2->desc_nr;
@@ -866,25 +856,6 @@ static void super_90_sync(mddev_t *mddev
 		if (test_bit(WriteMostly, &rdev2->flags))
 			d->state |= (1<<MD_DISK_WRITEMOSTLY);
 	}
-	if (fixdesc)
-		ITERATE_RDEV(mddev,rdev2,tmp)
-			if (fixdesc & (1<<rdev2->desc_nr)) {
-				snprintf(rdev2->kobj.name, KOBJ_NAME_LEN, "dev%d",
-					 rdev2->desc_nr);
-				/* kobject_add gets a ref on the parent, so
-				 * we have to drop the one we already have
-				 */
-				kobject_add(&rdev2->kobj);
-				kobject_put(rdev->kobj.parent);
-				sysfs_create_link(&rdev2->kobj,
-						  &rdev2->bdev->bd_disk->kobj,
-						  "block");
-				if (rdev2->raid_disk >= 0) {
-					sprintf(nm, "rd%d", rdev2->raid_disk);
-					sysfs_create_link(&mddev->kobj,
-							  &rdev2->kobj, nm);
-				}
-			}
 	/* now set the "removed" and "faulty" bits on any missing devices */
 	for (i=0 ; i < mddev->raid_disks ; i++) {
 		mdp_disk_t *d = &sb->disks[i];
@@ -1237,13 +1208,14 @@ static int bind_rdev_to_array(mdk_rdev_t
 		if (find_rdev_nr(mddev, rdev->desc_nr))
 			return -EBUSY;
 	}
+	bdevname(rdev->bdev,b);
+	if (kobject_set_name(&rdev->kobj, "dev-%s", b) < 0)
+		return -ENOMEM;
 			
 	list_add(&rdev->same_set, &mddev->disks);
 	rdev->mddev = mddev;
-	printk(KERN_INFO "md: bind<%s>\n", bdevname(rdev->bdev,b));
+	printk(KERN_INFO "md: bind<%s>\n", b);
 
-	rdev->kobj.k_name = NULL;
-	snprintf(rdev->kobj.name, KOBJ_NAME_LEN, "dev%d", rdev->desc_nr);
 	rdev->kobj.parent = &mddev->kobj;
 	kobject_add(&rdev->kobj);
 

[PATCH md 002 of 2] Allow md arrays to be started read-only (module parameter).

[NeilBrown]

When an md array is started, the superblock will be written,
and resync may commense.  This is not good if you want to be
completely read-only as, for example, when preparing to resume
from a suspend-to-disk image.

So introduce a module parameter "start_ro" which can be set
to '1' at boot, at module load, or via 
  /sys/module/md_mod/parameters/start_ro

When this is set, new arrays get an 'auto-ro' mode, which disables all
internal io (superblock updates, resync, recovery) and is automatically
switched to 'rw' when the first write request arrives.

The array can be set to true 'ro' mode using 'mdadm -r' before
the first write request, or resync can be started without a
write using 'mdadm -w'.

Signed-off-by: Neil Brown <neilb@suse.de>

### Diffstat output
 ./drivers/md/md.c |   59 ++++++++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 51 insertions(+), 8 deletions(-)

diff ./drivers/md/md.c~current~ ./drivers/md/md.c
--- ./drivers/md/md.c~current~	2005-10-31 15:54:59.000000000 +1100
+++ ./drivers/md/md.c	2005-10-31 15:55:06.000000000 +1100
@@ -131,6 +131,8 @@ static ctl_table raid_root_table[] = {
 
 static struct block_device_operations md_fops;
 
+static int start_readonly;
+
 /*
  * Enables to iterate over all existing md arrays
  * all_mddevs_lock protects this list.
@@ -2029,6 +2031,9 @@ static int do_md_run(mddev_t * mddev)
 	mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
 	mddev->barriers_work = 1;
 
+	if (start_readonly)
+		mddev->ro = 2; /* read-only, but switch on first write */
+
 	/* before we start the array running, initialise the bitmap */
 	err = bitmap_create(mddev);
 	if (err)
@@ -2141,7 +2146,7 @@ static int do_md_stop(mddev_t * mddev, i
 
 		if (ro) {
 			err  = -ENXIO;
-			if (mddev->ro)
+			if (mddev->ro==1)
 				goto out;
 			mddev->ro = 1;
 		} else {
@@ -3258,12 +3263,22 @@ static int md_ioctl(struct inode *inode,
 
 	/*
 	 * The remaining ioctls are changing the state of the
-	 * superblock, so we do not allow read-only arrays
-	 * here:
+	 * superblock, so we do not allow them on read-only arrays.
+	 * However non-MD ioctls (e.g. get-size) will still come through
+	 * here and hit the 'default' below, so only disallow
+	 * 'md' ioctls, and switch to rw mode if started auto-readonly.
 	 */
-	if (mddev->ro) {
-		err = -EROFS;
-		goto abort_unlock;
+	if (_IOC_TYPE(cmd) == MD_MAJOR &&
+	    mddev->ro && mddev->pers) {
+		if (mddev->ro == 2) {
+			mddev->ro = 0;
+		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+		md_wakeup_thread(mddev->thread);
+
+		} else {
+			err = -EROFS;
+			goto abort_unlock;
+		}
 	}
 
 	switch (cmd)
@@ -3651,8 +3666,10 @@ static int md_seq_show(struct seq_file *
 		seq_printf(seq, "%s : %sactive", mdname(mddev),
 						mddev->pers ? "" : "in");
 		if (mddev->pers) {
-			if (mddev->ro)
+			if (mddev->ro==1)
 				seq_printf(seq, " (read-only)");
+			if (mddev->ro==2)
+				seq_printf(seq, "(auto-read-only)");
 			seq_printf(seq, " %s", mddev->pers->name);
 		}
 
@@ -3696,7 +3713,9 @@ static int md_seq_show(struct seq_file *
 				status_resync (seq, mddev);
 				seq_printf(seq, "\n      ");
 			} else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
-				seq_printf(seq, "	resync=DELAYED\n      ");
+				seq_printf(seq, "\tresync=DELAYED\n      ");
+			else if (mddev->recovery_cp < MaxSector)
+				seq_printf(seq, "\tresync=PENDING\n      ");
 		} else
 			seq_printf(seq, "\n       ");
 
@@ -3833,6 +3852,13 @@ void md_write_start(mddev_t *mddev, stru
 	if (bio_data_dir(bi) != WRITE)
 		return;
 
+	BUG_ON(mddev->ro == 1);
+	if (mddev->ro == 2) {
+		/* need to switch to read/write */
+		mddev->ro = 0;
+		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+		md_wakeup_thread(mddev->thread);
+	}
 	atomic_inc(&mddev->writes_pending);
 	if (mddev->in_sync) {
 		spin_lock_irq(&mddev->write_lock);
@@ -4429,6 +4455,23 @@ static __exit void md_exit(void)
 module_init(md_init)
 module_exit(md_exit)
 
+static int get_ro(char *buffer, struct kernel_param *kp)
+{
+	return sprintf(buffer, "%d", start_readonly);
+}
+static int set_ro(const char *val, struct kernel_param *kp)
+{
+	char *e;
+	int num = simple_strtoul(val, &e, 10);
+	if (*val && (*e == '\0' || *e == '\n')) {
+		start_readonly = num;
+		return 0;;
+	}
+	return -EINVAL;
+}
+
+module_param_call(start_ro, set_ro, get_ro, NULL, 0600);
+
 EXPORT_SYMBOL(register_md_personality);
 EXPORT_SYMBOL(unregister_md_personality);
 EXPORT_SYMBOL(md_error);

Re: [PATCH md 000 of 2] Introduction

[Andrew Morton]

NeilBrown <neilb@suse.de> wrote:
>
> 
>  I'd like to review the sysfs a bit more before it goes to Linus, but
>  the rest can go anytime.

umm, what does "the sysfs" refer to?

Current md patches in -mm:

md-better-handling-of-readerrors-with-raid5.patch
md-initial-sysfs-support-for-md.patch
md-extend-md-sysfs-support-to-component-devices.patch
md-add-kobject-sysfs-support-to-raid5.patch
md-allow-a-manual-resync-with-md.patch
md-teach-raid5-the-difference-between-check-and-repair.patch
md-provide-proper-rcu_dereference--rcu_assign_pointer-annotations-in-md.patch
md-fix-ref-counting-problems-with-kobjects-in-md.patch
md-minor-md-fixes.patch
md-change-raid5-sysfs-attribute-to-not-create-a-new-directory.patch
md-improvements-to-raid5-handling-of-read-errors.patch
md-convert-faulty-and-in_sync-fields-to-bits-in-flags-field.patch
md-make-md-on-disk-bitmaps-not-host-endian.patch
md-support-bio_rw_barrier-for-md-raid1.patch
drivers-md-fix-up-schedule_timeout-usage.patch

Re: [PATCH md 000 of 2] Introduction

[Neil Brown]

On Sunday October 30, akpm@osdl.org wrote:
> NeilBrown <neilb@suse.de> wrote:
> >
> > 
> >  I'd like to review the sysfs a bit more before it goes to Linus, but
> >  the rest can go anytime.
> 
> umm, what does "the sysfs" refer to?

Sorry.. "the sysfs related patches".

Those marked as 'THIS' below.  

However I think a couple that come after those won't simple move
backwards (largely due to
md-convert-faulty-and-in_sync-fields-to-bits-in-flags-field).

I'll make sure you have a full set that I am happy to go to Linus by
the end of the week.

Thanks,
NeilBrown


> 
> Current md patches in -mm:
> 
> md-better-handling-of-readerrors-with-raid5.patch
THIS > md-initial-sysfs-support-for-md.patch
THIS > md-extend-md-sysfs-support-to-component-devices.patch
THIS > md-add-kobject-sysfs-support-to-raid5.patch
THIS > md-allow-a-manual-resync-with-md.patch
THIS > md-teach-raid5-the-difference-between-check-and-repair.patch
> md-provide-proper-rcu_dereference--rcu_assign_pointer-annotations-in-md.patch
THIS > md-fix-ref-counting-problems-with-kobjects-in-md.patch
THIS > md-minor-md-fixes.patch
THIS > md-change-raid5-sysfs-attribute-to-not-create-a-new-directory.patch
> md-improvements-to-raid5-handling-of-read-errors.patch
> md-convert-faulty-and-in_sync-fields-to-bits-in-flags-field.patch
> md-make-md-on-disk-bitmaps-not-host-endian.patch
> md-support-bio_rw_barrier-for-md-raid1.patch
> drivers-md-fix-up-schedule_timeout-usage.patch
> 
> -
> To unsubscribe from this list: send the line "unsubscribe linux-raid" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH md 000 of 2] Introduction

[Andrew Morton]

Neil Brown <neilb@suse.de> wrote:
>
> On Sunday October 30, akpm@osdl.org wrote:
> > NeilBrown <neilb@suse.de> wrote:
> > >
> > > 
> > >  I'd like to review the sysfs a bit more before it goes to Linus, but
> > >  the rest can go anytime.
> > 
> > umm, what does "the sysfs" refer to?
> 
> Sorry.. "the sysfs related patches".
> 
> Those marked as 'THIS' below.  
> 
> However I think a couple that come after those won't simple move
> backwards (largely due to
> md-convert-faulty-and-in_sync-fields-to-bits-in-flags-field).
> 
> I'll make sure you have a full set that I am happy to go to Linus by
> the end of the week.

hm, OK, that's a bit late in the process to be introducing new material, so
no later please.

Also, please make sure that Greg is copied on sysfs things - save me an
email ;)

Re: [PATCH md 000 of 2] Introduction

[Mr. James W. Laferriere]

	Hello Neil ,  The original '[PATCH md 000 of 2] Introduction' never hit 
	the list afaict .  Could you please re-send or if you did & only I am 
	without it send privately .  Tia ,  JimL

On Mon, 31 Oct 2005, Neil Brown wrote:
> On Sunday October 30, akpm@osdl.org wrote:
> > NeilBrown <neilb@suse.de> wrote:
> > >  I'd like to review the sysfs a bit more before it goes to Linus, but
> > >  the rest can go anytime.
> > umm, what does "the sysfs" refer to?
> Sorry.. "the sysfs related patches".
> Those marked as 'THIS' below.  
> However I think a couple that come after those won't simple move
> backwards (largely due to
> md-convert-faulty-and-in_sync-fields-to-bits-in-flags-field).
> I'll make sure you have a full set that I am happy to go to Linus by
> the end of the week.
> Thanks,
> NeilBrown
> > Current md patches in -mm:
> > md-better-handling-of-readerrors-with-raid5.patch
> THIS > md-initial-sysfs-support-for-md.patch
> THIS > md-extend-md-sysfs-support-to-component-devices.patch
> THIS > md-add-kobject-sysfs-support-to-raid5.patch
> THIS > md-allow-a-manual-resync-with-md.patch
> THIS > md-teach-raid5-the-difference-between-check-and-repair.patch
> > md-provide-proper-rcu_dereference--rcu_assign_pointer-annotations-in-md.patch
> THIS > md-fix-ref-counting-problems-with-kobjects-in-md.patch
> THIS > md-minor-md-fixes.patch
> THIS > md-change-raid5-sysfs-attribute-to-not-create-a-new-directory.patch
> > md-improvements-to-raid5-handling-of-read-errors.patch
> > md-convert-faulty-and-in_sync-fields-to-bits-in-flags-field.patch
> > md-make-md-on-disk-bitmaps-not-host-endian.patch
> > md-support-bio_rw_barrier-for-md-raid1.patch
> > drivers-md-fix-up-schedule_timeout-usage.patch
-- 
+------------------------------------------------------------------+
| James   W.   Laferriere | System    Techniques | Give me VMS     |
| Network        Engineer | 3542 Broken Yoke Dr. |  Give me Linux  |
| babydr@baby-dragons.com | Billings , MT. 59105 |   only  on  AXP |
+------------------------------------------------------------------+

Re: [PATCH md 000 of 2] Introduction

[Neil Brown]

On Monday October 31, babydr@baby-dragons.com wrote:
> 	Hello Neil ,  The original '[PATCH md 000 of 2] Introduction' never hit 
> 	the list afaict .  Could you please re-send or if you did & only I am 
> 	without it send privately .  Tia ,  JimL

I cannot knot who else is without it :-), but you can find it here.


http://marc.theaimsgroup.com/?l=linux-raid&m=113073839213484&w=2


NeilBrown

[PATCH md 000 of 2] Introduction

[NeilBrown]

Following are two patches for md in 2.6.15-rc what should get into
2.6.15-final if possible.

The first refines a newly created interface (/sys/block/mdX/md/level).
I've decided that 'raid5' is better than 'RAID-5' after all.

The second removes some limits that shouldn't really be imposed in the kernel.

Thanks,
NeilBrown



 [PATCH md 001 of 2] Change case of raid level reported in sys/mdX/md/level
 [PATCH md 002 of 2] Remove inappropriate limits in md/bitmap configuration.

[PATCH md 000 of 2] Introduction

[NeilBrown]

Following are two patches for md in 2.6.14-mm2 that are suitable to go
into the 2.6.15-rc series.

The first adds a date to the deprecation of START_ARRAY ioctl.

The second fixes a recently introduced problem that causes md threads
to permanently add to the load average (other than that, every works
fine).

 [PATCH md 001 of 2] Mark START_ARRAY deprecated with a date.
 [PATCH md 002 of 2] Make md threads interruptible again.

Re: [PATCH md 000 of 2] Introduction

[Mr. James W. Laferriere]

 	Hello Neil ,

On Tue, 15 Nov 2005, NeilBrown wrote:
> Following are two patches for md in 2.6.14-mm2 that are suitable to go
> into the 2.6.15-rc series.
>
> The first adds a date to the deprecation of START_ARRAY ioctl.
>
> The second fixes a recently introduced problem that causes md threads
> to permanently add to the load average (other than that, every works
> fine).
>
> [PATCH md 001 of 2] Mark START_ARRAY deprecated with a date.
> [PATCH md 002 of 2] Make md threads interruptible again.

> diff ./Documentation/feature-removal-schedule.txt~current~ /Documentation/feature-removal-schedule.txt
> --- ./Documentation/feature-removal-schedule.txt~current~       2005-11-15 10:25:30.000000000 +1100
> +++ ./Documentation/feature-removal-schedule.txt        2005-11-15 10:25:30.000000000 +1100
> @@ -131,3 +131,12 @@ What:      EXPORT_SYMBOL(lookup_hash)
>  When:  January 2006
>  Why:   Too low-level interface.  Use lookup_one_len or lookup_create instead.
>  Who:   Christoph Hellwig <hch@lst.de>
> +
> +---------------------------
> +
> +What:  START_ARRAY ioctl for md
> +When:  July 2006
> +Files: drivers/md/md.c
> +Why:   Not reliable by design - can fail when most needed.
> +       Alternatives exist
> +Who:   NeilBrown <neilb@suse.de>

 	Would some please update Documentation/md.txt with the alternates
 	that exist to replace START_ARRAY ?  Or for that matter any kernel
 	related document that covers the md driver &/or its tools .
 		Tia ,  JimL

-- 
+------------------------------------------------------------------+
| James   W.   Laferriere | System    Techniques | Give me VMS     |
| Network        Engineer | 3542 Broken Yoke Dr. |  Give me Linux  |
| babydr@baby-dragons.com | Billings , MT. 59105 |   only  on  AXP |
+------------------------------------------------------------------+

Re: [PATCH md 000 of 2] Introduction

[Neil Brown]

On Tuesday November 15, babydr@baby-dragons.com wrote:
>  	Hello Neil ,
> 
> On Tue, 15 Nov 2005, NeilBrown wrote:
> > +
> > +---------------------------
> > +
> > +What:  START_ARRAY ioctl for md
> > +When:  July 2006
> > +Files: drivers/md/md.c
> > +Why:   Not reliable by design - can fail when most needed.
> > +       Alternatives exist
> > +Who:   NeilBrown <neilb@suse.de>
> 
>  	Would some please update Documentation/md.txt with the alternates
>  	that exist to replace START_ARRAY ?  Or for that matter any kernel
>  	related document that covers the md driver &/or its tools .
>  		Tia ,  JimL
> 

Are you just asking "What are the 'Alternatives' that are claimed to
exist?"?
If so, then it is  'mdadm -A'.  I guess I could make that more
explicit.

Or are you asking something else?

NeilBrown

Re: [PATCH md 000 of 2] Introduction

[Mr. James W. Laferriere]

  	Hello Neil ,

On Thu, 17 Nov 2005, Neil Brown wrote:
> On Tuesday November 15, babydr@baby-dragons.com wrote:
>> On Tue, 15 Nov 2005, NeilBrown wrote:
>>> +
>>> +---------------------------
>>> +
>>> +What:  START_ARRAY ioctl for md
>>> +When:  July 2006
>>> +Files: drivers/md/md.c
>>> +Why:   Not reliable by design - can fail when most needed.
>>> +       Alternatives exist
>>> +Who:   NeilBrown <neilb@suse.de>
>>
>>  	Would some please update Documentation/md.txt with the alternates
>>  	that exist to replace START_ARRAY ?  Or for that matter any kernel
>>  	related document that covers the md driver &/or its tools .
>>  		Tia ,  JimL
> Are you just asking "What are the 'Alternatives' that are claimed to
> exist?"?
 	Yes ,  And to have them documented .

> If so, then it is  'mdadm -A'.  I guess I could make that more
> explicit.
 	Hmm ,  Where is mdadm documented as linux-raid tool(set) IN the
 	kernel tree ?  It's not in md.txt ..
# grep mdadm /usr/src/linux/Documentation/md.txt
#
 	Please help me(us) here .

> Or are you asking something else?
 	No ,  You got it right .  Tia ,  JimL
-- 
+------------------------------------------------------------------+
| James   W.   Laferriere | System    Techniques | Give me VMS     |
| Network        Engineer | 3542 Broken Yoke Dr. |  Give me Linux  |
| babydr@baby-dragons.com | Billings , MT. 59105 |   only  on  AXP |
+------------------------------------------------------------------+

[PATCH md 000 of 2] Introduction

[NeilBrown]

Following are two very trivial patches against 2.6.13-rc6.
If 2.6.13 is still open for such trivial fixes, it would be good for
them to go in, but if not, I won't loose any sleep over it.

The first arranges that the first open of /dev/mdX will auto-load the
md modules (I don't know when that functionality disappeared).
The second fixes a possibly problem where-by if you stop an array and
create a new one on the same md device, it might not start any resync
that might be needed.

Thanks,
NeilBrown


 [PATCH md 001 of 2] Create a MODULE_ALIAS for md corresponding to it's block major number.
 [PATCH md 002 of 2] Clear the 'recovery' flags when starting an md array.

[PATCH md 000 of 2] Introduction

[NeilBrown]

Hi again,
 two more patches for md follow.  Both raid1 related.
 These are happy to sit in the queue for after 2.6.12.

Thanks,
NeilBrown

 [PATCH md 001 of 2] Cause md/raid1 to "repack" working devices when number of drives is changed.
 [PATCH md 002 of 2] Make sure recovery happens when add_new_disk is used for hot_add

[PATCH md 000 of 2] Introduction

[NeilBrown]

Two patches against 2.6.12-rc2 for md.
(patches apply to 2.6.12-rc2-mm1 with various offsets).

The first closes an extreme small race in md thread deregistration.
This race was actually lost by someone who, due to a different bug
which has since been fixed, has md threads being created and destroyed
at a very high rate.

The second removes a number of MD_BUG calls that that are either
completely pointless, or misleading (i.e. the report a bug when it is
just an unusual condition that is handled correctly).

NeilBrown


 [PATCH md 001 of 2] Close a small race in md thread deregistration
 [PATCH md 002 of 2] Remove a number of misleading calls to MD_BUG