Patch "mm/memory_hotplug: make __remove_pages() and arch_remove_memory() never fail" has been added to the 4.19-stable tree

From: <gregkh@linuxfoundation.org>
To: 20190409100148.24703-5-david@redhat.com,akpm@linux-foundation.org,andrew.banman@hpe.com,aneesh.kumar@linux.ibm.com,arunks@codeaurora.org,benh@kernel.crashing.org,bhe@redhat.com,bp@alien8.de,cai@lca.pw,christophe.leroy@c-s.fr,dalias@libc.org,dan.j.williams@intel.com,dave.hansen@linux.intel.com,david@redhat.com,fenghua.yu@intel.com,geert@linux-m68k.org,gor@linux.ibm.com,gregkh@linuxfoundation.org,heiko.carstens@de.ibm.com,hpa@zytor.com,iamjoonsoo.kim@lge.com,kirill.shutemov@linux.intel.com,linux-mm@kvack.org,luto@kernel.org,malat@debian.org,mhocko@suse.com,mike.travis@hpe.com,mingo@kernel.org,mingo@redhat.com,mpe@ellerman.id.au,npiggin@gmail.com,osalvador@suse.com,osalvador@suse.de,pasha.tatashin@soleen.com,paulus@samba.org,peterz@infradead.org,rafael@kernel.org,richard.weiyang@gmail.com,robh@kernel.org,rppt@linux.ibm.com,schwidefsky@de.ibm.com,stefan@agner.ch,tglx@linutronix.de,tony.luck@intel.com,torvalds@linux-foundation.org,yamada.masahiro@socionext.com,ysato@users.sour
	ceforge. jp
Cc: <stable-commits@vger.kernel.org>
Subject: Patch "mm/memory_hotplug: make __remove_pages() and arch_remove_memory() never fail" has been added to the 4.19-stable tree
Date: Tue, 28 Jan 2020 14:49:41 +0100	[thread overview]
Message-ID: <158021938164132@kroah.com> (raw)
In-Reply-To: <20200128095021.8076-13-david@redhat.com>


This is a note to let you know that I've just added the patch titled

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

to the 4.19-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail.patch
and it can be found in the queue-4.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


From foo@baz Tue 28 Jan 2020 02:32:10 PM CET
From: David Hildenbrand <david@redhat.com>
Date: Tue, 28 Jan 2020 10:50:09 +0100
Subject: mm/memory_hotplug: make __remove_pages() and arch_remove_memory() never fail
To: stable@vger.kernel.org
Cc: linux-mm@kvack.org, Michal Hocko <mhocko@suse.com>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Andrew Morton <akpm@linux-foundation.org>, "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>, Baoquan He <bhe@redhat.com>, Dan Williams <dan.j.williams@intel.com>, Oscar Salvador <osalvador@suse.de>, Wei Yang <richard.weiyang@gmail.com>, David Hildenbrand <david@redhat.com>
Message-ID: <20200128095021.8076-13-david@redhat.com>

From: David Hildenbrand <david@redhat.com>

commit ac5c94264580f498e484c854031d0226b3c1038f upstream.

-- snip --

Minor conflict in arch/powerpc/mm/mem.c

-- snip --

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@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Oscar Salvador <osalvador@suse.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Stefan Agner <stefan@agner.ch>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Arun KS <arunks@codeaurora.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Mathieu Malaterre <malat@debian.org>
Cc: Andrew Banman <andrew.banman@hpe.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mike Travis <mike.travis@hpe.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/ia64/mm/init.c            |   11 +++--------
 arch/powerpc/mm/mem.c          |    9 +++------
 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, 24 insertions(+), 40 deletions(-)

--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -662,20 +662,15 @@ 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
+++ b/arch/powerpc/mm/mem.c
@@ -140,7 +140,7 @@ int __ref arch_add_memory(int nid, u64 s
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-int __ref arch_remove_memory(int nid, u64 start, u64 size,
+void __ref arch_remove_memory(int nid, u64 start, u64 size,
 			     struct vmem_altmap *altmap)
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
@@ -156,14 +156,13 @@ int __ref arch_remove_memory(int nid, u6
 	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
@@ -171,8 +170,6 @@ int __ref arch_remove_memory(int nid, u6
 	vm_unmap_aliases();
 
 	resize_hpt_for_hotplug(memblock_phys_mem_size());
-
-	return ret;
 }
 #endif
 #endif /* CONFIG_MEMORY_HOTPLUG */
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -240,14 +240,15 @@ 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
+++ b/arch/sh/mm/init.c
@@ -444,20 +444,15 @@ 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
+++ b/arch/x86/mm/init_32.c
@@ -861,14 +861,15 @@ 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
+++ b/arch/x86/mm/init_64.c
@@ -1142,24 +1142,20 @@ 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
+++ b/include/linux/memory_hotplug.h
@@ -109,10 +109,10 @@ 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 */
 
 /* reasonably generic interface to expand the physical pages */
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -509,8 +509,8 @@ 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;
@@ -541,7 +541,6 @@ int __remove_pages(struct zone *zone, un
 	}
 
 	set_zone_contiguous(zone);
-	return 0;
 }
 #endif /* CONFIG_MEMORY_HOTREMOVE */
 


Patches currently in stable-queue which might be from david@redhat.com are

queue-4.19/mm-memory_hotplug-remove-memory-block-devices-before-arch_remove_memory.patch
queue-4.19/mm-hotplug-kill-is_dev_zone-usage-in-__remove_pages.patch
queue-4.19/mm-memory_hotplug-create-memory-block-devices-after-arch_add_memory.patch
queue-4.19/drivers-base-memory-pass-a-block_id-to-init_memory_block.patch
queue-4.19/drivers-base-memory.c-clean-up-relics-in-function-parameters.patch
queue-4.19/mm-memory_hotplug-update-a-comment-in-unregister_memory.patch
queue-4.19/mm-memory_hotplug-shrink-zones-when-offlining-memory.patch
queue-4.19/mm-memory_hotplug-make-unregister_memory_block_under_nodes-never-fail.patch
queue-4.19/mm-memunmap-don-t-access-uninitialized-memmap-in-memunmap_pages.patch
queue-4.19/mm-memory_hotplug-make-__remove_section-never-fail.patch
queue-4.19/mm-sparse-drop-pgdat_resize_lock-in-sparse_add-remove_one_section.patch
queue-4.19/mm-memory_hotplug-make-unregister_memory_section-never-fail.patch
queue-4.19/mm-memory_hotplug-release-memory-resource-after-arch_remove_memory.patch
queue-4.19/mm-memory_hotplug-add-nid-parameter-to-arch_remove_memory.patch
queue-4.19/powerpc-mm-fix-section-mismatch-warning.patch
queue-4.19/mm-memory_hotplug-allow-arch_remove_memory-without-config_memory_hotremove.patch
queue-4.19/mm-memory_hotplug-make-remove_memory-take-the-device_hotplug_lock.patch
queue-4.19/mm-memory_hotplug-make-__remove_pages-and-arch_remove_memory-never-fail.patch
queue-4.19/mm-memory_hotplug-fix-try_offline_node.patch
queue-4.19/mm-memory_hotplug-remove-zone-parameter-from-sparse_remove_one_section.patch
queue-4.19/drivers-base-memory.c-remove-an-unnecessary-check-on-nr_mem_sections.patch
queue-4.19/drivers-base-node.c-simplify-unregister_memory_block_under_nodes.patch
queue-4.19/s390x-mm-implement-arch_remove_memory.patch
queue-4.19/mm-sparse-pass-nid-instead-of-pgdat-to-sparse_add_one_section.patch

