On Mon 10-04-17 12:20:02, Jerome Glisse wrote:
> On Mon, Apr 10, 2017 at 01:03:46PM +0200, Michal Hocko wrote:
[...]
> > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
> > index 342332f29364..1570b3eea493 100644
> > --- a/mm/memory_hotplug.c
> > +++ b/mm/memory_hotplug.c
> > @@ -493,7 +493,7 @@ static int __meminit __add_zone(struct zone *zone,
> > unsigned long phys_start_pfn)
> > }
> >
> > static int __meminit __add_section(int nid, struct zone *zone,
> > - unsigned long phys_start_pfn)
> > + unsigned long phys_start_pfn, bool
> > want_memblock)
> > {
> > int ret;
> >
> > @@ -510,7 +510,10 @@ static int __meminit __add_section(int nid, struct
> > zone *zone,
> > if (ret < 0)
> > return ret;
> >
> > - return register_new_memory(nid, __pfn_to_section(phys_start_pfn));
> > + if (want_memblock)
> > + ret = register_new_memory(nid,
> > __pfn_to_section(phys_start_pfn));
> > +
> > + return ret;
> > }
>
> The above is wrong for ZONE_DEVICE sparse_add_one_section() will return a
> positive value (on success) thus ret > 0 and other function in the hotplug
> path will interpret positive value as an error.
>
> I suggest something like:
> if (!want_memblock)
> return 0;
>
> return register_new_memory(nid, __pfn_to_section(phys_start_pfn));
> }
You are right! I will fold the following. Thanks!
---
>From cc44b4a465b889910e74b3ccc2d12f4dd1c79065 Mon Sep 17 00:00:00 2001
From: Michal Hocko <mho...@suse.com>
Date: Mon, 10 Apr 2017 18:29:11 +0200
Subject: [PATCH] fold me "mm, memory_hotplug: get rid of
is_zone_device_section"
- return 0 want_memblock == 0 from __add_section as per Jerome Glisse
---
mm/memory_hotplug.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 035165ceefef..9942d8937d0a 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -299,7 +299,8 @@ void __init register_page_bootmem_info_node(struct
pglist_data *pgdat)
}
#endif /* CONFIG_HAVE_BOOTMEM_INFO_NODE */
-static int __meminit __add_section(int nid, unsigned long phys_start_pfn, bool
want_memblock)
+static int __meminit __add_section(int nid, unsigned long phys_start_pfn,
+ bool want_memblock)
{
int ret;
int i;
@@ -328,10 +329,10 @@ static int __meminit __add_section(int nid, unsigned long
phys_start_pfn, bool w
SetPageReserved(page);
}
- if (want_memblock)
- ret = register_new_memory(nid,
__pfn_to_section(phys_start_pfn));
+ if (!want_memblock)
+ return 0
- return ret;
+ return register_new_memory(nid, __pfn_to_section(phys_start_pfn));
}
/*
--
2.11.0
--
Michal Hocko
SUSE Labs
