mm/memory_hotplug: make __remove_pages() and arch_remove_memory() never fail

All callers of arch_remove_memory() ignore errors.  And we should really
try to remove any errors from the memory removal path.  No more errors are
reported from __remove_pages().  BUG() in s390x code in case
arch_remove_memory() is triggered.  We may implement that properly later.
WARN in case powerpc code failed to remove the section mapping, which is
better than ignoring the error completely right now.

Signed-off-by: David Hildenbrand <>
Cc: Tony Luck <>
Cc: Fenghua Yu <>
Cc: Benjamin Herrenschmidt <>
Cc: Paul Mackerras <>
Cc: Michael Ellerman <>
Cc: Martin Schwidefsky <>
Cc: Heiko Carstens <>
Cc: Yoshinori Sato <>
Cc: Rich Felker <>
Cc: Dave Hansen <>
Cc: Andy Lutomirski <>
Cc: Peter Zijlstra <>
Cc: Thomas Gleixner <>
Cc: Ingo Molnar <>
Cc: Borislav Petkov <>
Cc: "H. Peter Anvin" <>
Cc: Michal Hocko <>
Cc: Mike Rapoport <>
Cc: Oscar Salvador <>
Cc: "Kirill A. Shutemov" <>
Cc: Christophe Leroy <>
Cc: Stefan Agner <>
Cc: Nicholas Piggin <>
Cc: Pavel Tatashin <>
Cc: Vasily Gorbik <>
Cc: Arun KS <>
Cc: Geert Uytterhoeven <>
Cc: Masahiro Yamada <>
Cc: Rob Herring <>
Cc: Joonsoo Kim <>
Cc: Wei Yang <>
Cc: Qian Cai <>
Cc: Mathieu Malaterre <>
Cc: Andrew Banman <>
Cc: Greg Kroah-Hartman <>
Cc: Ingo Molnar <>
Cc: Mike Travis <>
Cc: Oscar Salvador <>
Cc: "Rafael J. Wysocki" <>
Signed-off-by: Andrew Morton <>
Signed-off-by: Linus Torvalds <>
8 files changed