[PATCH -mm] mm: Fix memory hotplug + sparsemem build.

[PATCH -mm] mm: Fix memory hotplug + sparsemem build.

[Paul Mundt]

Building with CONFIG_MEMORY_HOTPLUG_SPARSE enabled results in:

  CC      mm/memory_hotplug.o
mm/memory_hotplug.c: In function 'online_pages':
mm/memory_hotplug.c:215: error: 'struct zone' has no member named 'node'
make[1]: *** [mm/memory_hotplug.o] Error 1
make: *** [mm] Error 2

Fix it up.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

--

 mm/memory_hotplug.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- linux-2.6.23-rc4-mm1.orig/mm/memory_hotplug.c	2007-09-11 15:15:56.000000000 +0900
+++ linux-2.6.23-rc4-mm1/mm/memory_hotplug.c	2007-09-11 16:20:03.000000000 +0900
@@ -212,7 +212,7 @@
 	zone->present_pages += onlined_pages;
 	zone->zone_pgdat->node_present_pages += onlined_pages;
 	if (onlined_pages)
-		node_set_state(zone->node, N_HIGH_MEMORY);
+		node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
 
 	setup_per_zone_pages_min();
 

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Re: [PATCH -mm] mm: Fix memory hotplug + sparsemem build.

[Yasunori Goto]

>  	if (onlined_pages)
> -		node_set_state(zone->node, N_HIGH_MEMORY);
> +		node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
>  
>  	setup_per_zone_pages_min();

Thanks Paul-san. 

I also have another issue around here.
(Kswapd doesn't run on memory less node now. It should run when
 the node has memory.)

I would like to merge them like following if you don't mind.


Bye.

---

Fix kswapd doesn't run when memory is added on memory-less-node.
Fix compile error of zone->node when CONFIG_NUMA is off.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>


---
 mm/memory_hotplug.c |    9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

Index: current/mm/memory_hotplug.c
===================================================================
--- current.orig/mm/memory_hotplug.c	2007-09-07 18:08:07.000000000 +0900
+++ current/mm/memory_hotplug.c	2007-09-11 17:29:19.000000000 +0900
@@ -211,10 +211,12 @@ int online_pages(unsigned long pfn, unsi
 		online_pages_range);
 	zone->present_pages += onlined_pages;
 	zone->zone_pgdat->node_present_pages += onlined_pages;
-	if (onlined_pages)
-		node_set_state(zone->node, N_HIGH_MEMORY);
 
 	setup_per_zone_pages_min();
+	if (onlined_pages){
+		kswapd_run(zone_to_nid(zone));
+		node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
+	}
 
 	if (need_zonelists_rebuild)
 		build_all_zonelists();
@@ -269,9 +271,6 @@ int add_memory(int nid, u64 start, u64 s
 		if (!pgdat)
 			return -ENOMEM;
 		new_pgdat = 1;
-		ret = kswapd_run(nid);
-		if (ret)
-			goto error;
 	}
 
 	/* call arch's memory hotadd */


-- 
Yasunori Goto 


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Re: [PATCH -mm] mm: Fix memory hotplug + sparsemem build.

[Paul Mundt]

Hi Goto-san,

On Tue, Sep 11, 2007 at 05:18:01PM +0900, Yasunori Goto wrote:
> >  	if (onlined_pages)
> > -		node_set_state(zone->node, N_HIGH_MEMORY);
> > +		node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
> >  
> >  	setup_per_zone_pages_min();
> 
> Thanks Paul-san. 
> 
> I also have another issue around here.
> (Kswapd doesn't run on memory less node now. It should run when
>  the node has memory.)
> 
> I would like to merge them like following if you don't mind.
> 
Looks fine to me!

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Re: [PATCH -mm] mm: Fix memory hotplug + sparsemem build.

[Andy Whitcroft]

On Tue, Sep 11, 2007 at 05:18:01PM +0900, Yasunori Goto wrote:
> >  	if (onlined_pages)
> > -		node_set_state(zone->node, N_HIGH_MEMORY);
> > +		node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
> >  
> >  	setup_per_zone_pages_min();
> 
> Thanks Paul-san. 
> 
> I also have another issue around here.
> (Kswapd doesn't run on memory less node now. It should run when
>  the node has memory.)
> 
> I would like to merge them like following if you don't mind.
> 
> 
> Bye.
> 
> ---
> 
> Fix kswapd doesn't run when memory is added on memory-less-node.
> Fix compile error of zone->node when CONFIG_NUMA is off.
> 
> Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
> 
> 
> ---
>  mm/memory_hotplug.c |    9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
> 
> Index: current/mm/memory_hotplug.c
> ===================================================================
> --- current.orig/mm/memory_hotplug.c	2007-09-07 18:08:07.000000000 +0900
> +++ current/mm/memory_hotplug.c	2007-09-11 17:29:19.000000000 +0900
> @@ -211,10 +211,12 @@ int online_pages(unsigned long pfn, unsi
>  		online_pages_range);
>  	zone->present_pages += onlined_pages;
>  	zone->zone_pgdat->node_present_pages += onlined_pages;
> -	if (onlined_pages)
> -		node_set_state(zone->node, N_HIGH_MEMORY);
>  
>  	setup_per_zone_pages_min();
> +	if (onlined_pages){

Nit, needs a space there before the '{'.

> +		kswapd_run(zone_to_nid(zone));
> +		node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
> +	}
>  
>  	if (need_zonelists_rebuild)
>  		build_all_zonelists();
> @@ -269,9 +271,6 @@ int add_memory(int nid, u64 start, u64 s
>  		if (!pgdat)
>  			return -ENOMEM;
>  		new_pgdat = 1;
> -		ret = kswapd_run(nid);
> -		if (ret)
> -			goto error;
>  	}
>  
>  	/* call arch's memory hotadd */

The problem as I see it is that when we boot the system we start a
kswapd on all nodes with memory.  If the hot-add adds memory to a
pre-existing node with no memory we will not start one and we end up
with a node with memory and no kswapd.  Bad.

As kswapd_run is a no-op when a kswapd already exists this seems a safe
way to fix that.  Paul's ->zone conversion is obviously correct also.

Acked-by: Andy Whitcroft <apw@shadowen.org>

-apw

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Re: [PATCH -mm] mm: Fix memory hotplug + sparsemem build.

[Yasunori Goto]

> > +	if (onlined_pages){
> 
> Nit, needs a space there before the '{'.

Ah, Ok. I attached fixed patch in this mail.

> The problem as I see it is that when we boot the system we start a
> kswapd on all nodes with memory.  If the hot-add adds memory to a
> pre-existing node with no memory we will not start one and we end up
> with a node with memory and no kswapd.  Bad.
> 
> As kswapd_run is a no-op when a kswapd already exists this seems a safe
> way to fix that.  Paul's ->zone conversion is obviously correct also.
> 
> Acked-by: Andy Whitcroft <apw@shadowen.org>

Thanks for your explanation.
You mentioned all of my intention correctly. :-)


----

Fix kswapd doesn't run when memory is added on memory-less-node.
Fix compile error of zone->node when CONFIG_NUMA is off.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Andy Whitcroft <apw@shadowen.org>


---
 mm/memory_hotplug.c |    9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

Index: current/mm/memory_hotplug.c
===================================================================
--- current.orig/mm/memory_hotplug.c	2007-09-07 18:08:07.000000000 +0900
+++ current/mm/memory_hotplug.c	2007-09-11 17:29:19.000000000 +0900
@@ -211,10 +211,12 @@ int online_pages(unsigned long pfn, unsi
 		online_pages_range);
 	zone->present_pages += onlined_pages;
 	zone->zone_pgdat->node_present_pages += onlined_pages;
-	if (onlined_pages)
-		node_set_state(zone->node, N_HIGH_MEMORY);
 
 	setup_per_zone_pages_min();
+	if (onlined_pages) {
+		kswapd_run(zone_to_nid(zone));
+		node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
+	}
 
 	if (need_zonelists_rebuild)
 		build_all_zonelists();
@@ -269,9 +271,6 @@ int add_memory(int nid, u64 start, u64 s
 		if (!pgdat)
 			return -ENOMEM;
 		new_pgdat = 1;
-		ret = kswapd_run(nid);
-		if (ret)
-			goto error;
 	}
 
 	/* call arch's memory hotadd */

-- 
Yasunori Goto 


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Re: [PATCH -mm] mm: Fix memory hotplug + sparsemem build.

[Andrew Morton]

On Tue, 11 Sep 2007 18:37:12 +0900 Yasunori Goto <y-goto@jp.fujitsu.com> wrote:

> 
> > > +	if (onlined_pages){
> > 
> > Nit, needs a space there before the '{'.
> 
> Ah, Ok. I attached fixed patch in this mail.
> 
> > The problem as I see it is that when we boot the system we start a
> > kswapd on all nodes with memory.  If the hot-add adds memory to a
> > pre-existing node with no memory we will not start one and we end up
> > with a node with memory and no kswapd.  Bad.
> > 
> > As kswapd_run is a no-op when a kswapd already exists this seems a safe
> > way to fix that.  Paul's ->zone conversion is obviously correct also.
> > 
> > Acked-by: Andy Whitcroft <apw@shadowen.org>
> 
> Thanks for your explanation.
> You mentioned all of my intention correctly. :-)
> 
> 
> ----
> 
> Fix kswapd doesn't run when memory is added on memory-less-node.
> Fix compile error of zone->node when CONFIG_NUMA is off.
> 
> Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
> Acked-by: Andy Whitcroft <apw@shadowen.org>
> 
> 
> ---
>  mm/memory_hotplug.c |    9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
> 
> Index: current/mm/memory_hotplug.c
> ===================================================================
> --- current.orig/mm/memory_hotplug.c	2007-09-07 18:08:07.000000000 +0900
> +++ current/mm/memory_hotplug.c	2007-09-11 17:29:19.000000000 +0900
> @@ -211,10 +211,12 @@ int online_pages(unsigned long pfn, unsi
>  		online_pages_range);
>  	zone->present_pages += onlined_pages;
>  	zone->zone_pgdat->node_present_pages += onlined_pages;
> -	if (onlined_pages)
> -		node_set_state(zone->node, N_HIGH_MEMORY);
>  
>  	setup_per_zone_pages_min();
> +	if (onlined_pages) {
> +		kswapd_run(zone_to_nid(zone));
> +		node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
> +	}
>  
>  	if (need_zonelists_rebuild)
>  		build_all_zonelists();
> @@ -269,9 +271,6 @@ int add_memory(int nid, u64 start, u64 s
>  		if (!pgdat)
>  			return -ENOMEM;
>  		new_pgdat = 1;
> -		ret = kswapd_run(nid);
> -		if (ret)
> -			goto error;
>  	}
>  
>  	/* call arch's memory hotadd */
> 

OK, we're getting into a mess here.  This patch fixes
update-n_high_memory-node-state-for-memory-hotadd.patch, but which patch
does update-n_high_memory-node-state-for-memory-hotadd.patch fix?

At present I just whacked
update-n_high_memory-node-state-for-memory-hotadd.patch at the end of
everything, but that was lazy of me and it ends up making a mess.

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Re: [PATCH -mm] mm: Fix memory hotplug + sparsemem build.

[Yasunori Goto]

> On Tue, 11 Sep 2007 18:37:12 +0900 Yasunori Goto <y-goto@jp.fujitsu.com> wrote:
> 
> > 
> > > > +	if (onlined_pages){
> > > 
> > > Nit, needs a space there before the '{'.
> > 
> > Ah, Ok. I attached fixed patch in this mail.
> > 
> > > The problem as I see it is that when we boot the system we start a
> > > kswapd on all nodes with memory.  If the hot-add adds memory to a
> > > pre-existing node with no memory we will not start one and we end up
> > > with a node with memory and no kswapd.  Bad.
> > > 
> > > As kswapd_run is a no-op when a kswapd already exists this seems a safe
> > > way to fix that.  Paul's ->zone conversion is obviously correct also.
> > > 
> > > Acked-by: Andy Whitcroft <apw@shadowen.org>
> > 
> > Thanks for your explanation.
> > You mentioned all of my intention correctly. :-)
> > 
> > 
> > ----
> > 
> > Fix kswapd doesn't run when memory is added on memory-less-node.
> > Fix compile error of zone->node when CONFIG_NUMA is off.
> > 
> > Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
> > Signed-off-by: Paul Mundt <lethal@linux-sh.org>
> > Acked-by: Andy Whitcroft <apw@shadowen.org>
> > 
> > 
> > ---
> >  mm/memory_hotplug.c |    9 ++++-----
> >  1 file changed, 4 insertions(+), 5 deletions(-)
> > 
> > Index: current/mm/memory_hotplug.c
> > ===================================================================
> > --- current.orig/mm/memory_hotplug.c	2007-09-07 18:08:07.000000000 +0900
> > +++ current/mm/memory_hotplug.c	2007-09-11 17:29:19.000000000 +0900
> > @@ -211,10 +211,12 @@ int online_pages(unsigned long pfn, unsi
> >  		online_pages_range);
> >  	zone->present_pages += onlined_pages;
> >  	zone->zone_pgdat->node_present_pages += onlined_pages;
> > -	if (onlined_pages)
> > -		node_set_state(zone->node, N_HIGH_MEMORY);
> >  
> >  	setup_per_zone_pages_min();
> > +	if (onlined_pages) {
> > +		kswapd_run(zone_to_nid(zone));
> > +		node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
> > +	}
> >  
> >  	if (need_zonelists_rebuild)
> >  		build_all_zonelists();
> > @@ -269,9 +271,6 @@ int add_memory(int nid, u64 start, u64 s
> >  		if (!pgdat)
> >  			return -ENOMEM;
> >  		new_pgdat = 1;
> > -		ret = kswapd_run(nid);
> > -		if (ret)
> > -			goto error;
> >  	}
> >  
> >  	/* call arch's memory hotadd */
> > 
> 
> OK, we're getting into a mess here.  This patch fixes
> update-n_high_memory-node-state-for-memory-hotadd.patch, but which patch
> does update-n_high_memory-node-state-for-memory-hotadd.patch fix?
> 
> At present I just whacked
> update-n_high_memory-node-state-for-memory-hotadd.patch at the end of
> everything, but that was lazy of me and it ends up making a mess.

It is enough. No more patch is necessary for these issues.
I already fixed about Andy-san's comment. :-)


Thanks.
-- 
Yasunori Goto 


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Re: [PATCH -mm] mm: Fix memory hotplug + sparsemem build.

[Andrew Morton]

On Fri, 14 Sep 2007 11:02:43 +0900 Yasunori Goto <y-goto@jp.fujitsu.com> wrote:

> > >  	/* call arch's memory hotadd */
> > > 
> > 
> > OK, we're getting into a mess here.  This patch fixes
> > update-n_high_memory-node-state-for-memory-hotadd.patch, but which patch
> > does update-n_high_memory-node-state-for-memory-hotadd.patch fix?
> > 
> > At present I just whacked
> > update-n_high_memory-node-state-for-memory-hotadd.patch at the end of
> > everything, but that was lazy of me and it ends up making a mess.
> 
> It is enough. No more patch is necessary for these issues.
> I already fixed about Andy-san's comment. :-)

Now I'm more confused.  I have two separeate questions:

a) Is the justr-added update-n_high_memory-node-state-for-memory-hotadd-fix.patch
   still needed?

b) Which patch in 2.6.22-rc4-mm1 does
   update-n_high_memory-node-state-for-memory-hotadd.patch fix?  In other
   words, into which patch should I fold
   update-n_high_memory-node-state-for-memory-hotadd.patch prior to sending
   to Linus?

   (I (usually) get to work this out for myself.  Sometimes it is painful).

Generally, if people tell me which patch-in-mm their patch is fixing,
it really helps.  Adrian does this all the time.

Thanks.

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Re: [PATCH -mm] mm: Fix memory hotplug + sparsemem build.

[Yasunori Goto]

> On Fri, 14 Sep 2007 11:02:43 +0900 Yasunori Goto <y-goto@jp.fujitsu.com> wrote:
> 
> > > >  	/* call arch's memory hotadd */
> > > > 
> > > 
> > > OK, we're getting into a mess here.  This patch fixes
> > > update-n_high_memory-node-state-for-memory-hotadd.patch, but which patch
> > > does update-n_high_memory-node-state-for-memory-hotadd.patch fix?
> > > 
> > > At present I just whacked
> > > update-n_high_memory-node-state-for-memory-hotadd.patch at the end of
> > > everything, but that was lazy of me and it ends up making a mess.
> > 
> > It is enough. No more patch is necessary for these issues.
> > I already fixed about Andy-san's comment. :-)
> 
> Now I'm more confused.  I have two separeate questions:
> 
> a) Is the justr-added update-n_high_memory-node-state-for-memory-hotadd-fix.patch
>    still needed?

I'm not sure exact meaning of "just-added". 
But, update-n_high_memory-node-state-for-memory-hotadd-fix.patch is
necessary for 2.6.23-rc4-mm1.

> b) Which patch in 2.6.22-rc4-mm1 does

                    2.6.23-rc4-mm1?

>    update-n_high_memory-node-state-for-memory-hotadd.patch fix?  In other
>    words, into which patch should I fold
>    update-n_high_memory-node-state-for-memory-hotadd.patch prior to sending
>    to Linus?

In my understanding, 
update-n_high_memory-node-state-for-memory-hotadd.patch should be folded
with all of memoryless-nodes-xxxxxxxxxxxx.patch.
It sets N_HIGH_MEMORY for a new node-with-memory.

But if you need specifing of more detail patch, becase N_HIGH_MEMORY is
set in memoryless-nodes-introduce-ask-of-nodes-with-memory.patch, 
I suppose update-n_high_memory-node-state-for-memory-hotadd.patch
should be fold with it.


update-n_high_memory-node-state-for-memory-hotadd-fix.patch
                                                  ^^^
is fixes of update-n_high_memory-node-state-for-memory-hotadd.patch
and memoryless-nodes-no-need-for-kswapd.patch


Is it enough for your question? Or more confuse?


>    (I (usually) get to work this out for myself.  Sometimes it is painful).
> 
> Generally, if people tell me which patch-in-mm their patch is fixing,
> it really helps.  Adrian does this all the time.

Sorry for your confusing...


-- 
Yasunori Goto 


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Re: [PATCH -mm] mm: Fix memory hotplug + sparsemem build.

[Lee Schermerhorn]

On Thu, 2007-09-13 at 19:41 -0700, Andrew Morton wrote:
> On Fri, 14 Sep 2007 11:02:43 +0900 Yasunori Goto <y-goto@jp.fujitsu.com> wrote:
> 
> > > >  	/* call arch's memory hotadd */
> > > > 
> > > 
> > > OK, we're getting into a mess here.  This patch fixes
> > > update-n_high_memory-node-state-for-memory-hotadd.patch, but which patch
> > > does update-n_high_memory-node-state-for-memory-hotadd.patch fix?
> > > 
> > > At present I just whacked
> > > update-n_high_memory-node-state-for-memory-hotadd.patch at the end of
> > > everything, but that was lazy of me and it ends up making a mess.
> > 
> > It is enough. No more patch is necessary for these issues.
> > I already fixed about Andy-san's comment. :-)
> 
> Now I'm more confused.  I have two separeate questions:
> 
> a) Is the justr-added update-n_high_memory-node-state-for-memory-hotadd-fix.patch
>    still needed?
> 
> b) Which patch in 2.6.22-rc4-mm1 does
>    update-n_high_memory-node-state-for-memory-hotadd.patch fix?  In other
>    words, into which patch should I fold
>    update-n_high_memory-node-state-for-memory-hotadd.patch prior to sending
>    to Linus?

Andrew:  

I originally sent in the "update-n_high_memory..." patch against
23-rc3-mm1 on 27aug to fix a problem that I introduced when I moved the
populating of N_HIGH_MEMORY state to free_area_init_nodes().  This would
miss setting the "has memory" node state for hot added memory.  I never
saw any response, but then it ended up in 23-rc4-mm1.

This Tuesday, Paul Mundt sent in a patch to fix a build problem with
MEMORY_HOTPLUG_SPARSE introduced by my patch.  He replaced zone->node
with zone_to_nid(zone) in the node_set_state() arguments.

The latest patch, from Yasunori-san, I believe, starts kswapd for nodes
to which memory has been hot-added.  As I understand it, his is needed
because the memoryless nodes patch results in no kswapd for memoryless
nodes.

Does that help?

Lee


> 
>    (I (usually) get to work this out for myself.  Sometimes it is painful).
> 
> Generally, if people tell me which patch-in-mm their patch is fixing,
> it really helps.  Adrian does this all the time.
> 
> Thanks.
> 
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Re: [PATCH -mm] mm: Fix memory hotplug + sparsemem build.

[Andrew Morton]

On Fri, 14 Sep 2007 10:09:27 -0400
Lee Schermerhorn <Lee.Schermerhorn@hp.com> wrote:

> I originally sent in the "update-n_high_memory..." patch against
> 23-rc3-mm1 on 27aug to fix a problem that I introduced when I moved the
> populating of N_HIGH_MEMORY state to free_area_init_nodes().  This would
> miss setting the "has memory" node state for hot added memory.  I never
> saw any response, but then it ended up in 23-rc4-mm1.
> 
> This Tuesday, Paul Mundt sent in a patch to fix a build problem with
> MEMORY_HOTPLUG_SPARSE introduced by my patch.  He replaced zone->node
> with zone_to_nid(zone) in the node_set_state() arguments.
> 
> The latest patch, from Yasunori-san, I believe, starts kswapd for nodes
> to which memory has been hot-added.  As I understand it, his is needed
> because the memoryless nodes patch results in no kswapd for memoryless
> nodes.
> 
> Does that help?

not really ;)

See, when I get some rinky-dink little fix for a patch in -mm I will
position that patch immediately after the patch which it is fixing, with a
filename which is derived from the fixed patch's name.  So when
send-to-Linus time comes, I can fold the fixes into the base patch.  This
practice also keeps the patches in a sensible presentation order, with
minimum interdependencies and good git-bisect friendliness.

However it sometimes (rarely) takes considerable effort to work out which
patch in -mm a particular fix is fixing.  That was the case with
update-n_high_memory-node-state-for-memory-hotadd.patch.

It helps me quite a bit if people tell me which patch they're fixing. 
Usually they don't and I get to work it out.  Usually it's fairly obvious.

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