The patch titled
Subject: mm/memory_hotplug: make unregister_memory_section() never fail
has been added to the -mm tree. Its filename is
mm-memory_hotplug-make-unregister_memory_section-never-fail.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-memory_hotplug-make-unregister_memory_section-never-fail.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-memory_hotplug-make-unregister_memory_section-never-fail.patch
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------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: mm/memory_hotplug: make unregister_memory_section() never fail
Failing while removing memory is mostly ignored and cannot really be
handled. Let's treat errors in unregister_memory_section() in a nice way,
warning, but continuing.
Link: http://lkml.kernel.org/r/20190409100148.24703-3-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Andrew Banman <andrew.banman@xxxxxxx>
Cc: Mike Travis <mike.travis@xxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Cc: Qian Cai <cai@xxxxxx>
Cc: Wei Yang <richard.weiyang@xxxxxxxxx>
Cc: Arun KS <arunks@xxxxxxxxxxxxxx>
Cc: Mathieu Malaterre <malat@xxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Rich Felker <dalias@xxxxxxxx>
Cc: Rob Herring <robh@xxxxxxxxxx>
Cc: Stefan Agner <stefan@xxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/base/memory.c | 16 +++++-----------
include/linux/memory.h | 2 +-
mm/memory_hotplug.c | 4 +---
3 files changed, 7 insertions(+), 15 deletions(-)
--- a/drivers/base/memory.c~mm-memory_hotplug-make-unregister_memory_section-never-fail
+++ a/drivers/base/memory.c
@@ -734,15 +734,18 @@ unregister_memory(struct memory_block *m
{
BUG_ON(memory->dev.bus != &memory_subsys);
- /* drop the ref. we got in remove_memory_section() */
+ /* drop the ref. we got via find_memory_block() */
put_device(&memory->dev);
device_unregister(&memory->dev);
}
-static int remove_memory_section(struct mem_section *section)
+void unregister_memory_section(struct mem_section *section)
{
struct memory_block *mem;
+ if (WARN_ON_ONCE(!present_section(section)))
+ return;
+
mutex_lock(&mem_sysfs_mutex);
/*
@@ -763,15 +766,6 @@ static int remove_memory_section(struct
out_unlock:
mutex_unlock(&mem_sysfs_mutex);
- return 0;
-}
-
-int unregister_memory_section(struct mem_section *section)
-{
- if (!present_section(section))
- return -EINVAL;
-
- return remove_memory_section(section);
}
#endif /* CONFIG_MEMORY_HOTREMOVE */
--- a/include/linux/memory.h~mm-memory_hotplug-make-unregister_memory_section-never-fail
+++ a/include/linux/memory.h
@@ -113,7 +113,7 @@ extern int register_memory_isolate_notif
extern void unregister_memory_isolate_notifier(struct notifier_block *nb);
int hotplug_memory_register(int nid, struct mem_section *section);
#ifdef CONFIG_MEMORY_HOTREMOVE
-extern int unregister_memory_section(struct mem_section *);
+extern void unregister_memory_section(struct mem_section *);
#endif
extern int memory_dev_init(void);
extern int memory_notify(unsigned long val, void *v);
--- a/mm/memory_hotplug.c~mm-memory_hotplug-make-unregister_memory_section-never-fail
+++ a/mm/memory_hotplug.c
@@ -526,9 +526,7 @@ static int __remove_section(struct zone
if (!valid_section(ms))
return ret;
- ret = unregister_memory_section(ms);
- if (ret)
- return ret;
+ unregister_memory_section(ms);
scn_nr = __section_nr(ms);
start_pfn = section_nr_to_pfn((unsigned long)scn_nr);
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
mm-balloon-drop-unused-function-stubs.patch
mm-memory_hotplug-release-memory-resource-after-arch_remove_memory.patch
mm-memory_hotplug-make-unregister_memory_section-never-fail.patch
mm-memory_hotplug-make-__remove_section-never-fail.patch
mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail.patch
