This is a note to let you know that I've just added the patch titled mm/memory_hotplug: make __remove_section() 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_section-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@xxxxxxxxxxxxxxx> know about it. >From foo@baz Tue 28 Jan 2020 02:32:10 PM CET From: David Hildenbrand <david@xxxxxxxxxx> Date: Tue, 28 Jan 2020 10:50:07 +0100 Subject: mm/memory_hotplug: make __remove_section() never fail To: stable@xxxxxxxxxxxxxxx Cc: linux-mm@xxxxxxxxx, Michal Hocko <mhocko@xxxxxxxx>, Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>, "Aneesh Kumar K . V" <aneesh.kumar@xxxxxxxxxxxxx>, Baoquan He <bhe@xxxxxxxxxx>, Dan Williams <dan.j.williams@xxxxxxxxx>, Oscar Salvador <osalvador@xxxxxxx>, Wei Yang <richard.weiyang@xxxxxxxxx>, David Hildenbrand <david@xxxxxxxxxx> Message-ID: <20200128095021.8076-11-david@xxxxxxxxxx> From: David Hildenbrand <david@xxxxxxxxxx> commit 9d1d887d785b4fe0590bd3c5e71acaa3908044e2 upstream. Let's just warn in case a section is not valid instead of failing to remove somewhere in the middle of the process, returning an error that will be mostly ignored by callers. Link: http://lkml.kernel.org/r/20190409100148.24703-4-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Reviewed-by: Oscar Salvador <osalvador@xxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> 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: Andrew Banman <andrew.banman@xxxxxxx> 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: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> 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: Mike Travis <mike.travis@xxxxxxx> Cc: Nicholas Piggin <npiggin@xxxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx> 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> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- mm/memory_hotplug.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -478,15 +478,15 @@ static void __remove_zone(struct zone *z pgdat_resize_unlock(zone->zone_pgdat, &flags); } -static int __remove_section(struct zone *zone, struct mem_section *ms, - unsigned long map_offset, struct vmem_altmap *altmap) +static void __remove_section(struct zone *zone, struct mem_section *ms, + unsigned long map_offset, + struct vmem_altmap *altmap) { unsigned long start_pfn; int scn_nr; - int ret = -EINVAL; - if (!valid_section(ms)) - return ret; + if (WARN_ON_ONCE(!valid_section(ms))) + return; unregister_memory_section(ms); @@ -495,7 +495,6 @@ static int __remove_section(struct zone __remove_zone(zone, start_pfn); sparse_remove_one_section(zone, ms, map_offset, altmap); - return 0; } /** @@ -515,7 +514,7 @@ int __remove_pages(struct zone *zone, un { unsigned long i; unsigned long map_offset = 0; - int sections_to_remove, ret = 0; + int sections_to_remove; /* In the ZONE_DEVICE case device driver owns the memory region */ if (is_dev_zone(zone)) { @@ -536,16 +535,13 @@ int __remove_pages(struct zone *zone, un unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION; cond_resched(); - ret = __remove_section(zone, __pfn_to_section(pfn), map_offset, - altmap); + __remove_section(zone, __pfn_to_section(pfn), map_offset, + altmap); map_offset = 0; - if (ret) - break; } set_zone_contiguous(zone); - - return ret; + return 0; } #endif /* CONFIG_MEMORY_HOTREMOVE */ Patches currently in stable-queue which might be from david@xxxxxxxxxx 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