The patch titled
Subject: mm/memory_hotplug: make __remove_pages() and arch_remove_memory() never fail
has been added to the -mm tree. Its filename is
mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: 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.
Link: http://lkml.kernel.org/r/20190409100148.24703-5-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
Cc: Rich Felker <dalias@xxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxxx>
Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxx>
Cc: Stefan Agner <stefan@xxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Cc: Arun KS <arunks@xxxxxxxxxxxxxx>
Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Cc: Rob Herring <robh@xxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: Wei Yang <richard.weiyang@xxxxxxxxx>
Cc: Qian Cai <cai@xxxxxx>
Cc: Mathieu Malaterre <malat@xxxxxxxxxx>
Cc: Andrew Banman <andrew.banman@xxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Mike Travis <mike.travis@xxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/ia64/mm/init.c | 11 +++--------
arch/powerpc/mm/mem.c | 11 ++++-------
arch/s390/mm/init.c | 5 +++--
arch/sh/mm/init.c | 11 +++--------
arch/x86/mm/init_32.c | 5 +++--
arch/x86/mm/init_64.c | 10 +++-------
include/linux/memory_hotplug.h | 8 ++++----
mm/memory_hotplug.c | 5 ++---
8 files changed, 25 insertions(+), 41 deletions(-)
--- a/arch/ia64/mm/init.c~mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail
+++ a/arch/ia64/mm/init.c
@@ -682,20 +682,15 @@ int arch_add_memory(int nid, u64 start,
}
#ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap)
+void arch_remove_memory(int nid, u64 start, u64 size,
+ struct vmem_altmap *altmap)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
struct zone *zone;
- int ret;
zone = page_zone(pfn_to_page(start_pfn));
- ret = __remove_pages(zone, start_pfn, nr_pages, altmap);
- if (ret)
- pr_warn("%s: Problem encountered in __remove_pages() as"
- " ret=%d\n", __func__, ret);
-
- return ret;
+ __remove_pages(zone, start_pfn, nr_pages, altmap);
}
#endif
#endif
--- a/arch/powerpc/mm/mem.c~mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail
+++ a/arch/powerpc/mm/mem.c
@@ -131,8 +131,8 @@ int __meminit arch_add_memory(int nid, u
}
#ifdef CONFIG_MEMORY_HOTREMOVE
-int __meminit arch_remove_memory(int nid, u64 start, u64 size,
- struct vmem_altmap *altmap)
+void __meminit arch_remove_memory(int nid, u64 start, u64 size,
+ struct vmem_altmap *altmap)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
@@ -147,14 +147,13 @@ int __meminit arch_remove_memory(int nid
if (altmap)
page += vmem_altmap_offset(altmap);
- ret = __remove_pages(page_zone(page), start_pfn, nr_pages, altmap);
- if (ret)
- return ret;
+ __remove_pages(page_zone(page), start_pfn, nr_pages, altmap);
/* Remove htab bolted mappings for this section of memory */
start = (unsigned long)__va(start);
flush_inval_dcache_range(start, start + size);
ret = remove_section_mapping(start, start + size);
+ WARN_ON_ONCE(ret);
/* Ensure all vmalloc mappings are flushed in case they also
* hit that section of memory
@@ -162,8 +161,6 @@ int __meminit arch_remove_memory(int nid
vm_unmap_aliases();
resize_hpt_for_hotplug(memblock_phys_mem_size());
-
- return ret;
}
#endif
#endif /* CONFIG_MEMORY_HOTPLUG */
--- a/arch/s390/mm/init.c~mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail
+++ a/arch/s390/mm/init.c
@@ -234,14 +234,15 @@ int arch_add_memory(int nid, u64 start,
}
#ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap)
+void arch_remove_memory(int nid, u64 start, u64 size,
+ struct vmem_altmap *altmap)
{
/*
* There is no hardware or firmware interface which could trigger a
* hot memory remove on s390. So there is nothing that needs to be
* implemented.
*/
- return -EBUSY;
+ BUG();
}
#endif
#endif /* CONFIG_MEMORY_HOTPLUG */
--- a/arch/sh/mm/init.c~mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail
+++ a/arch/sh/mm/init.c
@@ -429,20 +429,15 @@ EXPORT_SYMBOL_GPL(memory_add_physaddr_to
#endif
#ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap)
+void arch_remove_memory(int nid, u64 start, u64 size,
+ struct vmem_altmap *altmap)
{
unsigned long start_pfn = PFN_DOWN(start);
unsigned long nr_pages = size >> PAGE_SHIFT;
struct zone *zone;
- int ret;
zone = page_zone(pfn_to_page(start_pfn));
- ret = __remove_pages(zone, start_pfn, nr_pages, altmap);
- if (unlikely(ret))
- pr_warn("%s: Failed, __remove_pages() == %d\n", __func__,
- ret);
-
- return ret;
+ __remove_pages(zone, start_pfn, nr_pages, altmap);
}
#endif
#endif /* CONFIG_MEMORY_HOTPLUG */
--- a/arch/x86/mm/init_32.c~mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail
+++ a/arch/x86/mm/init_32.c
@@ -860,14 +860,15 @@ int arch_add_memory(int nid, u64 start,
}
#ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap)
+void arch_remove_memory(int nid, u64 start, u64 size,
+ struct vmem_altmap *altmap)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
struct zone *zone;
zone = page_zone(pfn_to_page(start_pfn));
- return __remove_pages(zone, start_pfn, nr_pages, altmap);
+ __remove_pages(zone, start_pfn, nr_pages, altmap);
}
#endif
#endif
--- a/arch/x86/mm/init_64.c~mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail
+++ a/arch/x86/mm/init_64.c
@@ -1141,24 +1141,20 @@ kernel_physical_mapping_remove(unsigned
remove_pagetable(start, end, true, NULL);
}
-int __ref arch_remove_memory(int nid, u64 start, u64 size,
- struct vmem_altmap *altmap)
+void __ref arch_remove_memory(int nid, u64 start, u64 size,
+ struct vmem_altmap *altmap)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
struct page *page = pfn_to_page(start_pfn);
struct zone *zone;
- int ret;
/* With altmap the first mapped page is offset from @start */
if (altmap)
page += vmem_altmap_offset(altmap);
zone = page_zone(page);
- ret = __remove_pages(zone, start_pfn, nr_pages, altmap);
- WARN_ON_ONCE(ret);
+ __remove_pages(zone, start_pfn, nr_pages, altmap);
kernel_physical_mapping_remove(start, start + size);
-
- return ret;
}
#endif
#endif /* CONFIG_MEMORY_HOTPLUG */
--- a/include/linux/memory_hotplug.h~mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail
+++ a/include/linux/memory_hotplug.h
@@ -124,10 +124,10 @@ static inline bool movable_node_is_enabl
}
#ifdef CONFIG_MEMORY_HOTREMOVE
-extern int arch_remove_memory(int nid, u64 start, u64 size,
- struct vmem_altmap *altmap);
-extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
- unsigned long nr_pages, struct vmem_altmap *altmap);
+extern void arch_remove_memory(int nid, u64 start, u64 size,
+ struct vmem_altmap *altmap);
+extern void __remove_pages(struct zone *zone, unsigned long start_pfn,
+ unsigned long nr_pages, struct vmem_altmap *altmap);
#endif /* CONFIG_MEMORY_HOTREMOVE */
/*
--- a/mm/memory_hotplug.c~mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail
+++ a/mm/memory_hotplug.c
@@ -547,8 +547,8 @@ static void __remove_section(struct zone
* sure that pages are marked reserved and zones are adjust properly by
* calling offline_pages().
*/
-int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
- unsigned long nr_pages, struct vmem_altmap *altmap)
+void __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
+ unsigned long nr_pages, struct vmem_altmap *altmap)
{
unsigned long i;
unsigned long map_offset = 0;
@@ -579,7 +579,6 @@ int __remove_pages(struct zone *zone, un
}
set_zone_contiguous(zone);
- return 0;
}
#endif /* CONFIG_MEMORY_HOTREMOVE */
_
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
