This is a note to let you know that I've just added the patch titled mm/memory_hotplug: make unregister_memory_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-unregister_memory_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 10:50:06 +0100 Subject: mm/memory_hotplug: make unregister_memory_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: <20200128095021.8076-10-david@xxxxxxxxxx> From: David Hildenbrand <david@xxxxxxxxxx> commit cb7b3a3685b20d3b5900ff24b2cb96d002960189 upstream. 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> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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 +++ b/drivers/base/memory.c @@ -743,15 +743,18 @@ 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); /* @@ -772,15 +775,6 @@ 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 +++ b/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 +++ b/mm/memory_hotplug.c @@ -488,9 +488,7 @@ 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 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