1. 01 Feb, 2020 16 commits
  2. 29 Jan, 2020 24 commits
    • Greg Kroah-Hartman's avatar
      Linux 4.19.100 · 7cdefde3
      Greg Kroah-Hartman authored
      7cdefde3
    • David Hildenbrand's avatar
      mm/memory_hotplug: shrink zones when offlining memory · 86834898
      David Hildenbrand authored
      commit feee6b29 upstream.
      
      -- snip --
      
      - Missing arm64 hot(un)plug support
      - Missing some vmem_altmap_offset() cleanups
      - Missing sub-section hotadd support
      - Missing unification of mm/hmm.c and kernel/memremap.c
      
      -- snip --
      
      We currently try to shrink a single zone when removing memory.  We use
      the zone of the first page of the memory we are removing.  If that
      memmap was never initialized (e.g., memory was never onlined), we will
      read garbage and can trigger kernel BUGs (due to a stale pointer):
      
          BUG: unable to handle page fault for address: 000000000000353d
          #PF: supervisor write access in kernel mode
          #PF: error_code(0x0002) - not-present page
          PGD 0 P4D 0
          Oops: 0002 [#1] SMP PTI
          CPU: 1 PID: 7 Comm: kworker/u8:0 Not tainted 5.3.0-rc5-next-20190820+ #317
          Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.4
          Workqueue: kacpi_hotplug acpi_hotplug_work_fn
          RIP: 0010:clear_zone_contiguous+0x5/0x10
          Code: 48 89 c6 48 89 c3 e8 2a fe ff ff 48 85 c0 75 cf 5b 5d c3 c6 85 fd 05 00 00 01 5b 5d c3 0f 1f 840
          RSP: 0018:ffffad2400043c98 EFLAGS: 00010246
          RAX: 0000000000000000 RBX: 0000000200000000 RCX: 0000000000000000
          RDX: 0000000000200000 RSI: 0000000000140000 RDI: 0000000000002f40
          RBP: 0000000140000000 R08: 0000000000000000 R09: 0000000000000001
          R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000140000
          R13: 0000000000140000 R14: 0000000000002f40 R15: ffff9e3e7aff3680
          FS:  0000000000000000(0000) GS:ffff9e3e7bb00000(0000) knlGS:0000000000000000
          CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
          CR2: 000000000000353d CR3: 0000000058610000 CR4: 00000000000006e0
          DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
          DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
          Call Trace:
           __remove_pages+0x4b/0x640
           arch_remove_memory+0x63/0x8d
           try_remove_memory+0xdb/0x130
           __remove_memory+0xa/0x11
           acpi_memory_device_remove+0x70/0x100
           acpi_bus_trim+0x55/0x90
           acpi_device_hotplug+0x227/0x3a0
           acpi_hotplug_work_fn+0x1a/0x30
           process_one_work+0x221/0x550
           worker_thread+0x50/0x3b0
           kthread+0x105/0x140
           ret_from_fork+0x3a/0x50
          Modules linked in:
          CR2: 000000000000353d
      
      Instead, shrink the zones when offlining memory or when onlining failed.
      Introduce and use remove_pfn_range_from_zone(() for that.  We now
      properly shrink the zones, even if we have DIMMs whereby
      
       - Some memory blocks fall into no zone (never onlined)
      
       - Some memory blocks fall into multiple zones (offlined+re-onlined)
      
       - Multiple memory blocks that fall into different zones
      
      Drop the zone parameter (with a potential dubious value) from
      __remove_pages() and __remove_section().
      
      Link: http://lkml.kernel.org/r/20191006085646.5768-6-david@redhat.com
      Fixes: f1dd2cd1 ("mm, memory_hotplug: do not associate hotadded memory to zones until online")	[visible after d0dc12e8]
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Reviewed-by: default avatarOscar Salvador <osalvador@suse.de>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
      Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: <stable@vger.kernel.org>	[5.0+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      86834898
    • David Hildenbrand's avatar
      mm/memory_hotplug: fix try_offline_node() · d98d053e
      David Hildenbrand authored
      commit 2c91f8fc upstream.
      
      -- snip --
      
      Only contextual issues:
      - Unrelated check_and_unmap_cpu_on_node() changes are missing.
      - Unrelated walk_memory_blocks() has not been moved/refactored yet.
      
      -- snip --
      
      try_offline_node() is pretty much broken right now:
      
       - The node span is updated when onlining memory, not when adding it. We
         ignore memory that was mever onlined. Bad.
      
       - We touch possible garbage memmaps. The pfn_to_nid(pfn) can easily
         trigger a kernel panic. Bad for memory that is offline but also bad
         for subsection hotadd with ZONE_DEVICE, whereby the memmap of the
         first PFN of a section might contain garbage.
      
       - Sections belonging to mixed nodes are not properly considered.
      
      As memory blocks might belong to multiple nodes, we would have to walk
      all pageblocks (or at least subsections) within present sections.
      However, we don't have a way to identify whether a memmap that is not
      online was initialized (relevant for ZONE_DEVICE).  This makes things
      more complicated.
      
      Luckily, we can piggy pack on the node span and the nid stored in memory
      blocks.  Currently, the node span is grown when calling
      move_pfn_range_to_zone() - e.g., when onlining memory, and shrunk when
      removing memory, before calling try_offline_node().  Sysfs links are
      created via link_mem_sections(), e.g., during boot or when adding
      memory.
      
      If the node still spans memory or if any memory block belongs to the
      nid, we don't set the node offline.  As memory blocks that span multiple
      nodes cannot get offlined, the nid stored in memory blocks is reliable
      enough (for such online memory blocks, the node still spans the memory).
      
      Introduce for_each_memory_block() to efficiently walk all memory blocks.
      
      Note: We will soon stop shrinking the ZONE_DEVICE zone and the node span
      when removing ZONE_DEVICE memory to fix similar issues (access of
      garbage memmaps) - until we have a reliable way to identify whether
      these memmaps were properly initialized.  This implies later, that once
      a node had ZONE_DEVICE memory, we won't be able to set a node offline -
      which should be acceptable.
      
      Since commit f1dd2cd1 ("mm, memory_hotplug: do not associate
      hotadded memory to zones until online") memory that is added is not
      assoziated with a zone/node (memmap not initialized).  The introducing
      commit 60a5a19e ("memory-hotplug: remove sysfs file of node")
      already missed that we could have multiple nodes for a section and that
      the zone/node span is updated when onlining pages, not when adding them.
      
      I tested this by hotplugging two DIMMs to a memory-less and cpu-less
      NUMA node.  The node is properly onlined when adding the DIMMs.  When
      removing the DIMMs, the node is properly offlined.
      
      Masayoshi Mizuma reported:
      
      : Without this patch, memory hotplug fails as panic:
      :
      :  BUG: kernel NULL pointer dereference, address: 0000000000000000
      :  ...
      :  Call Trace:
      :   remove_memory_block_devices+0x81/0xc0
      :   try_remove_memory+0xb4/0x130
      :   __remove_memory+0xa/0x20
      :   acpi_memory_device_remove+0x84/0x100
      :   acpi_bus_trim+0x57/0x90
      :   acpi_bus_trim+0x2e/0x90
      :   acpi_device_hotplug+0x2b2/0x4d0
      :   acpi_hotplug_work_fn+0x1a/0x30
      :   process_one_work+0x171/0x380
      :   worker_thread+0x49/0x3f0
      :   kthread+0xf8/0x130
      :   ret_from_fork+0x35/0x40
      
      [david@redhat.com: v3]
        Link: http://lkml.kernel.org/r/20191102120221.7553-1-david@redhat.com
      Link: http://lkml.kernel.org/r/20191028105458.28320-1-david@redhat.com
      Fixes: 60a5a19e ("memory-hotplug: remove sysfs file of node")
      Fixes: f1dd2cd1 ("mm, memory_hotplug: do not associate hotadded memory to zones until online") # visiable after d0dc12e8Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Tested-by: default avatarMasayoshi Mizuma <m.mizuma@jp.fujitsu.com>
      Cc: Tang Chen <tangchen@cn.fujitsu.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Keith Busch <keith.busch@intel.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
      Cc: Jani Nikula <jani.nikula@intel.com>
      Cc: Nayna Jain <nayna@linux.ibm.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Stephen Rothwell <sfr@canb.auug.org.au>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      d98d053e
    • Aneesh Kumar K.V's avatar
      mm/memunmap: don't access uninitialized memmap in memunmap_pages() · f2910806
      Aneesh Kumar K.V authored
      commit 77e080e7 upstream.
      
      -- snip --
      
      - Missing mm/hmm.c and kernel/memremap.c unification.
      -- hmm code does not need fixes (no altmap)
      - Missing 7cc7867f ("mm/devm_memremap_pages: enable sub-section remap")
      
      -- snip --
      
      Patch series "mm/memory_hotplug: Shrink zones before removing memory",
      v6.
      
      This series fixes the access of uninitialized memmaps when shrinking
      zones/nodes and when removing memory.  Also, it contains all fixes for
      crashes that can be triggered when removing certain namespace using
      memunmap_pages() - ZONE_DEVICE, reported by Aneesh.
      
      We stop trying to shrink ZONE_DEVICE, as it's buggy, fixing it would be
      more involved (we don't have SECTION_IS_ONLINE as an indicator), and
      shrinking is only of limited use (set_zone_contiguous() cannot detect
      the ZONE_DEVICE as contiguous).
      
      We continue shrinking !ZONE_DEVICE zones, however, I reduced the amount
      of code to a minimum.  Shrinking is especially necessary to keep
      zone->contiguous set where possible, especially, on memory unplug of
      DIMMs at zone boundaries.
      
      --------------------------------------------------------------------------
      
      Zones are now properly shrunk when offlining memory blocks or when
      onlining failed.  This allows to properly shrink zones on memory unplug
      even if the separate memory blocks of a DIMM were onlined to different
      zones or re-onlined to a different zone after offlining.
      
      Example:
      
        :/# cat /proc/zoneinfo
        Node 1, zone  Movable
                spanned  0
                present  0
                managed  0
        :/# echo "online_movable" > /sys/devices/system/memory/memory41/state
        :/# echo "online_movable" > /sys/devices/system/memory/memory43/state
        :/# cat /proc/zoneinfo
        Node 1, zone  Movable
                spanned  98304
                present  65536
                managed  65536
        :/# echo 0 > /sys/devices/system/memory/memory43/online
        :/# cat /proc/zoneinfo
        Node 1, zone  Movable
                spanned  32768
                present  32768
                managed  32768
        :/# echo 0 > /sys/devices/system/memory/memory41/online
        :/# cat /proc/zoneinfo
        Node 1, zone  Movable
                spanned  0
                present  0
                managed  0
      
      This patch (of 10):
      
      With an altmap, the memmap falling into the reserved altmap space are not
      initialized and, therefore, contain a garbage NID and a garbage zone.
      Make sure to read the NID/zone from a memmap that was initialized.
      
      This fixes a kernel crash that is observed when destroying a namespace:
      
        kernel BUG at include/linux/mm.h:1107!
        cpu 0x1: Vector: 700 (Program Check) at [c000000274087890]
            pc: c0000000004b9728: memunmap_pages+0x238/0x340
            lr: c0000000004b9724: memunmap_pages+0x234/0x340
        ...
            pid   = 3669, comm = ndctl
        kernel BUG at include/linux/mm.h:1107!
          devm_action_release+0x30/0x50
          release_nodes+0x268/0x2d0
          device_release_driver_internal+0x174/0x240
          unbind_store+0x13c/0x190
          drv_attr_store+0x44/0x60
          sysfs_kf_write+0x70/0xa0
          kernfs_fop_write+0x1ac/0x290
          __vfs_write+0x3c/0x70
          vfs_write+0xe4/0x200
          ksys_write+0x7c/0x140
          system_call+0x5c/0x68
      
      The "page_zone(pfn_to_page(pfn)" was introduced by 69324b8f ("mm,
      devm_memremap_pages: add MEMORY_DEVICE_PRIVATE support"), however, I
      think we will never have driver reserved memory with
      MEMORY_DEVICE_PRIVATE (no altmap AFAIKS).
      
      [david@redhat.com: minimze code changes, rephrase description]
      Link: http://lkml.kernel.org/r/20191006085646.5768-2-david@redhat.com
      Fixes: 2c2a5af6 ("mm, memory_hotplug: add nid parameter to arch_remove_memory")
      Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Jason Gunthorpe <jgg@ziepe.ca>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Ira Weiny <ira.weiny@intel.com>
      Cc: Damian Tometzki <damian.tometzki@gmail.com>
      Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
      Cc: Alexander Potapenko <glider@google.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Anshuman Khandual <anshuman.khandual@arm.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Christophe Leroy <christophe.leroy@c-s.fr>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Halil Pasic <pasic@linux.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jun Yao <yaojun8558363@gmail.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Mike Rapoport <rppt@linux.ibm.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Pankaj Gupta <pagupta@redhat.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Pavel Tatashin <pavel.tatashin@microsoft.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Qian Cai <cai@lca.pw>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Robin Murphy <robin.murphy@arm.com>
      Cc: Steve Capper <steve.capper@arm.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tom Lendacky <thomas.lendacky@amd.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Wei Yang <richard.weiyang@gmail.com>
      Cc: Wei Yang <richardw.yang@linux.intel.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: Yu Zhao <yuzhao@google.com>
      Cc: <stable@vger.kernel.org>	[5.0+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      f2910806
    • David Hildenbrand's avatar
      drivers/base/node.c: simplify unregister_memory_block_under_nodes() · d830a11c
      David Hildenbrand authored
      commit d84f2f5a upstream.
      
      We don't allow to offline memory block devices that belong to multiple
      numa nodes.  Therefore, such devices can never get removed.  It is
      sufficient to process a single node when removing the memory block.  No
      need to iterate over each and every PFN.
      
      We already have the nid stored for each memory block.  Make sure that the
      nid always has a sane value.
      
      Please note that checking for node_online(nid) is not required.  If we
      would have a memory block belonging to a node that is no longer offline,
      then we would have a BUG in the node offlining code.
      
      Link: http://lkml.kernel.org/r/20190719135244.15242-1-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: David Hildenbrand <david@redhat.com>
      Cc: Stephen Rothwell <sfr@canb.auug.org.au>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      d830a11c
    • Dan Williams's avatar
      mm/hotplug: kill is_dev_zone() usage in __remove_pages() · b9cda650
      Dan Williams authored
      commit 96da4350 upstream.
      
      -- snip --
      
      Minor conflict, keep the altmap check.
      
      -- snip --
      
      The zone type check was a leftover from the cleanup that plumbed altmap
      through the memory hotplug path, i.e.  commit da024512 "mm: pass the
      vmem_altmap to arch_remove_memory and __remove_pages".
      
      Link: http://lkml.kernel.org/r/156092352642.979959.6664333788149363039.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by: default avatarDan Williams <dan.j.williams@intel.com>
      Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
      Reviewed-by: default avatarOscar Salvador <osalvador@suse.de>
      Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>	[ppc64]
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Jane Chu <jane.chu@oracle.com>
      Cc: Jeff Moyer <jmoyer@redhat.com>
      Cc: Jérôme Glisse <jglisse@redhat.com>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Mike Rapoport <rppt@linux.ibm.com>
      Cc: Toshi Kani <toshi.kani@hpe.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Wei Yang <richardw.yang@linux.intel.com>
      Cc: Jason Gunthorpe <jgg@mellanox.com>
      Cc: Christoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b9cda650
    • David Hildenbrand's avatar
      mm/memory_hotplug: remove "zone" parameter from sparse_remove_one_section · dc6be859
      David Hildenbrand authored
      commit b9bf8d34 upstream.
      
      The parameter is unused, so let's drop it.  Memory removal paths should
      never care about zones.  This is the job of memory offlining and will
      require more refactorings.
      
      Link: http://lkml.kernel.org/r/20190527111152.16324-12-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Reviewed-by: default avatarDan Williams <dan.j.williams@intel.com>
      Reviewed-by: default avatarWei Yang <richardw.yang@linux.intel.com>
      Reviewed-by: default avatarOscar Salvador <osalvador@suse.de>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Alex Deucher <alexander.deucher@amd.com>
      Cc: Andrew Banman <andrew.banman@hpe.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Anshuman Khandual <anshuman.khandual@arm.com>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arun KS <arunks@codeaurora.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Chintan Pandya <cpandya@codeaurora.org>
      Cc: Christophe Leroy <christophe.leroy@c-s.fr>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Jun Yao <yaojun8558363@gmail.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Mark Brown <broonie@kernel.org>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: Mathieu Malaterre <malat@debian.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: "mike.travis@hpe.com" <mike.travis@hpe.com>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Qian Cai <cai@lca.pw>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Rob Herring <robh@kernel.org>
      Cc: Robin Murphy <robin.murphy@arm.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: Yu Zhao <yuzhao@google.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      dc6be859
    • David Hildenbrand's avatar
      mm/memory_hotplug: make unregister_memory_block_under_nodes() never fail · 030d045d
      David Hildenbrand authored
      commit a31b264c upstream.
      
      We really don't want anything during memory hotunplug to fail.  We
      always pass a valid memory block device, that check can go.  Avoid
      allocating memory and eventually failing.  As we are always called under
      lock, we can use a static piece of memory.  This avoids having to put
      the structure onto the stack, having to guess about the stack size of
      callers.
      
      Patch inspired by a patch from Oscar Salvador.
      
      In the future, there might be no need to iterate over nodes at all.
      mem->nid should tell us exactly what to remove.  Memory block devices
      with mixed nodes (added during boot) should properly fenced off and
      never removed.
      
      Link: http://lkml.kernel.org/r/20190527111152.16324-11-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Reviewed-by: default avatarWei Yang <richardw.yang@linux.intel.com>
      Reviewed-by: default avatarOscar Salvador <osalvador@suse.de>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Alex Deucher <alexander.deucher@amd.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Mark Brown <broonie@kernel.org>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: David Hildenbrand <david@redhat.com>
      Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
      Cc: Andrew Banman <andrew.banman@hpe.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Anshuman Khandual <anshuman.khandual@arm.com>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arun KS <arunks@codeaurora.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Chintan Pandya <cpandya@codeaurora.org>
      Cc: Christophe Leroy <christophe.leroy@c-s.fr>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Jun Yao <yaojun8558363@gmail.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: Mathieu Malaterre <malat@debian.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: "mike.travis@hpe.com" <mike.travis@hpe.com>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Qian Cai <cai@lca.pw>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Rob Herring <robh@kernel.org>
      Cc: Robin Murphy <robin.murphy@arm.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: Yu Zhao <yuzhao@google.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      030d045d
    • David Hildenbrand's avatar
      mm/memory_hotplug: remove memory block devices before arch_remove_memory() · d883abbc
      David Hildenbrand authored
      commit 4c4b7f9b upstream.
      
      Let's factor out removing of memory block devices, which is only
      necessary for memory added via add_memory() and friends that created
      memory block devices.  Remove the devices before calling
      arch_remove_memory().
      
      This finishes factoring out memory block device handling from
      arch_add_memory() and arch_remove_memory().
      
      Link: http://lkml.kernel.org/r/20190527111152.16324-10-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Reviewed-by: default avatarDan Williams <dan.j.williams@intel.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: David Hildenbrand <david@redhat.com>
      Cc: "mike.travis@hpe.com" <mike.travis@hpe.com>
      Cc: Andrew Banman <andrew.banman@hpe.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Alex Deucher <alexander.deucher@amd.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Mark Brown <broonie@kernel.org>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
      Cc: Arun KS <arunks@codeaurora.org>
      Cc: Mathieu Malaterre <malat@debian.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Anshuman Khandual <anshuman.khandual@arm.com>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Chintan Pandya <cpandya@codeaurora.org>
      Cc: Christophe Leroy <christophe.leroy@c-s.fr>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Jun Yao <yaojun8558363@gmail.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Oscar Salvador <osalvador@suse.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Qian Cai <cai@lca.pw>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Rob Herring <robh@kernel.org>
      Cc: Robin Murphy <robin.murphy@arm.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Wei Yang <richard.weiyang@gmail.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: Yu Zhao <yuzhao@google.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      d883abbc
    • David Hildenbrand's avatar
      mm/memory_hotplug: create memory block devices after arch_add_memory() · aa49b6ab
      David Hildenbrand authored
      commit db051a0d upstream.
      
      Only memory to be added to the buddy and to be onlined/offlined by user
      space using /sys/devices/system/memory/...  needs (and should have!)
      memory block devices.
      
      Factor out creation of memory block devices.  Create all devices after
      arch_add_memory() succeeded.  We can later drop the want_memblock
      parameter, because it is now effectively stale.
      
      Only after memory block devices have been added, memory can be onlined
      by user space.  This implies, that memory is not visible to user space
      at all before arch_add_memory() succeeded.
      
      While at it
       - use WARN_ON_ONCE instead of BUG_ON in moved unregister_memory()
       - introduce find_memory_block_by_id() to search via block id
       - Use find_memory_block_by_id() in init_memory_block() to catch
         duplicates
      
      Link: http://lkml.kernel.org/r/20190527111152.16324-8-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Reviewed-by: default avatarPavel Tatashin <pasha.tatashin@soleen.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: David Hildenbrand <david@redhat.com>
      Cc: "mike.travis@hpe.com" <mike.travis@hpe.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Andrew Banman <andrew.banman@hpe.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Qian Cai <cai@lca.pw>
      Cc: Wei Yang <richard.weiyang@gmail.com>
      Cc: Arun KS <arunks@codeaurora.org>
      Cc: Mathieu Malaterre <malat@debian.org>
      Cc: Alex Deucher <alexander.deucher@amd.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Anshuman Khandual <anshuman.khandual@arm.com>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Chintan Pandya <cpandya@codeaurora.org>
      Cc: Christophe Leroy <christophe.leroy@c-s.fr>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Jun Yao <yaojun8558363@gmail.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Mark Brown <broonie@kernel.org>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Oscar Salvador <osalvador@suse.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Rob Herring <robh@kernel.org>
      Cc: Robin Murphy <robin.murphy@arm.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: Yu Zhao <yuzhao@google.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      aa49b6ab
    • David Hildenbrand's avatar
      drivers/base/memory: pass a block_id to init_memory_block() · 97c60869
      David Hildenbrand authored
      commit 18115825 upstream.
      
      We'll rework hotplug_memory_register() shortly, so it no longer consumes
      pass a section.
      
      [cai@lca.pw: fix a compilation warning]
        Link: http://lkml.kernel.org/r/1559320186-28337-1-git-send-email-cai@lca.pw
      Link: http://lkml.kernel.org/r/20190527111152.16324-6-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarQian Cai <cai@lca.pw>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Alex Deucher <alexander.deucher@amd.com>
      Cc: Andrew Banman <andrew.banman@hpe.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Anshuman Khandual <anshuman.khandual@arm.com>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arun KS <arunks@codeaurora.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Chintan Pandya <cpandya@codeaurora.org>
      Cc: Christophe Leroy <christophe.leroy@c-s.fr>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Jun Yao <yaojun8558363@gmail.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Mark Brown <broonie@kernel.org>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: Mathieu Malaterre <malat@debian.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: "mike.travis@hpe.com" <mike.travis@hpe.com>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Oscar Salvador <osalvador@suse.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Rob Herring <robh@kernel.org>
      Cc: Robin Murphy <robin.murphy@arm.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Wei Yang <richard.weiyang@gmail.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: Yu Zhao <yuzhao@google.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      97c60869
    • David Hildenbrand's avatar
      mm/memory_hotplug: allow arch_remove_memory() without CONFIG_MEMORY_HOTREMOVE · 000a1d59
      David Hildenbrand authored
      commit 80ec922d upstream.
      
      -- snip --
      
      Missing arm64 memory hot(un)plug support.
      
      -- snip --
      
      We want to improve error handling while adding memory by allowing to use
      arch_remove_memory() and __remove_pages() even if
      CONFIG_MEMORY_HOTREMOVE is not set to e.g., implement something like:
      
      	arch_add_memory()
      	rc = do_something();
      	if (rc) {
      		arch_remove_memory();
      	}
      
      We won't get rid of CONFIG_MEMORY_HOTREMOVE for now, as it will require
      quite some dependencies for memory offlining.
      
      Link: http://lkml.kernel.org/r/20190527111152.16324-7-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Reviewed-by: default avatarPavel Tatashin <pasha.tatashin@soleen.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: 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: Borislav Petkov <bp@alien8.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: David Hildenbrand <david@redhat.com>
      Cc: Oscar Salvador <osalvador@suse.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Alex Deucher <alexander.deucher@amd.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Mark Brown <broonie@kernel.org>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Christophe Leroy <christophe.leroy@c-s.fr>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Rob Herring <robh@kernel.org>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: "mike.travis@hpe.com" <mike.travis@hpe.com>
      Cc: Andrew Banman <andrew.banman@hpe.com>
      Cc: Arun KS <arunks@codeaurora.org>
      Cc: Qian Cai <cai@lca.pw>
      Cc: Mathieu Malaterre <malat@debian.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Anshuman Khandual <anshuman.khandual@arm.com>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Chintan Pandya <cpandya@codeaurora.org>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Jun Yao <yaojun8558363@gmail.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Robin Murphy <robin.murphy@arm.com>
      Cc: Wei Yang <richard.weiyang@gmail.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Yu Zhao <yuzhao@google.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      000a1d59
    • David Hildenbrand's avatar
      s390x/mm: implement arch_remove_memory() · 817edd2b
      David Hildenbrand authored
      commit 18c86506 upstream.
      
      Will come in handy when wanting to handle errors after
      arch_add_memory().
      
      Link: http://lkml.kernel.org/r/20190527111152.16324-4-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: David Hildenbrand <david@redhat.com>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Oscar Salvador <osalvador@suse.com>
      Cc: Alex Deucher <alexander.deucher@amd.com>
      Cc: Andrew Banman <andrew.banman@hpe.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Anshuman Khandual <anshuman.khandual@arm.com>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arun KS <arunks@codeaurora.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Chintan Pandya <cpandya@codeaurora.org>
      Cc: Christophe Leroy <christophe.leroy@c-s.fr>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Jun Yao <yaojun8558363@gmail.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Mark Brown <broonie@kernel.org>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: Mathieu Malaterre <malat@debian.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Mike Rapoport <rppt@linux.ibm.com>
      Cc: "mike.travis@hpe.com" <mike.travis@hpe.com>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Qian Cai <cai@lca.pw>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Rob Herring <robh@kernel.org>
      Cc: Robin Murphy <robin.murphy@arm.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Wei Yang <richard.weiyang@gmail.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: Yu Zhao <yuzhao@google.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      817edd2b
    • David Hildenbrand's avatar
      mm/memory_hotplug: make __remove_pages() and arch_remove_memory() never fail · 5163b1ec
      David Hildenbrand authored
      commit ac5c9426 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.comSigned-off-by: default avatarDavid 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: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      5163b1ec
    • Aneesh Kumar K.V's avatar
      powerpc/mm: Fix section mismatch warning · 58ddf0b0
      Aneesh Kumar K.V authored
      commit 26ad2671 upstream.
      
      This patch fix the below section mismatch warnings.
      
      WARNING: vmlinux.o(.text+0x2d1f44): Section mismatch in reference from the function devm_memremap_pages_release() to the function .meminit.text:arch_remove_memory()
      WARNING: vmlinux.o(.text+0x2d265c): Section mismatch in reference from the function devm_memremap_pages() to the function .meminit.text:arch_add_memory()
      Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      58ddf0b0
    • David Hildenbrand's avatar
      mm/memory_hotplug: make __remove_section() never fail · efaa8fb8
      David Hildenbrand authored
      commit 9d1d887d 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@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Reviewed-by: default avatarOscar Salvador <osalvador@suse.de>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: David Hildenbrand <david@redhat.com>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Qian Cai <cai@lca.pw>
      Cc: Wei Yang <richard.weiyang@gmail.com>
      Cc: Arun KS <arunks@codeaurora.org>
      Cc: Mathieu Malaterre <malat@debian.org>
      Cc: Andrew Banman <andrew.banman@hpe.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Christophe Leroy <christophe.leroy@c-s.fr>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Mike Rapoport <rppt@linux.ibm.com>
      Cc: Mike Travis <mike.travis@hpe.com>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Oscar Salvador <osalvador@suse.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Rob Herring <robh@kernel.org>
      Cc: Stefan Agner <stefan@agner.ch>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      efaa8fb8
    • David Hildenbrand's avatar
      mm/memory_hotplug: make unregister_memory_section() never fail · 36976713
      David Hildenbrand authored
      commit cb7b3a36 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@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Andrew Banman <andrew.banman@hpe.com>
      Cc: Mike Travis <mike.travis@hpe.com>
      Cc: David Hildenbrand <david@redhat.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Qian Cai <cai@lca.pw>
      Cc: Wei Yang <richard.weiyang@gmail.com>
      Cc: Arun KS <arunks@codeaurora.org>
      Cc: Mathieu Malaterre <malat@debian.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Christophe Leroy <christophe.leroy@c-s.fr>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Mike Rapoport <rppt@linux.ibm.com>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Oscar Salvador <osalvador@suse.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Rob Herring <robh@kernel.org>
      Cc: Stefan Agner <stefan@agner.ch>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      36976713
    • Dan Carpenter's avatar
      mm, memory_hotplug: update a comment in unregister_memory() · 8893b51a
      Dan Carpenter authored
      commit 16df1456 upstream.
      
      The remove_memory_block() function was renamed to in commit
      cc292b0b ("drivers/base/memory.c: rename remove_memory_block() to
      remove_memory_section()").
      Signed-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      8893b51a
    • Baoquan He's avatar
      drivers/base/memory.c: clean up relics in function parameters · 9e59baa2
      Baoquan He authored
      commit 063b8a4c upstream.
      
      The input parameter 'phys_index' of memory_block_action() is actually the
      section number, but not the phys_index of memory_block.  This is a relic
      from the past when one memory block could only contain one section.
      Rename it to start_section_nr.
      
      And also in remove_memory_section(), the 'node_id' and 'phys_device'
      arguments are not used by anyone.  Remove them.
      
      Link: http://lkml.kernel.org/r/20190329144250.14315-2-bhe@redhat.comSigned-off-by: default avatarBaoquan He <bhe@redhat.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Reviewed-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Reviewed-by: default avatarMukesh Ojha <mojha@codeaurora.org>
      Reviewed-by: default avatarOscar Salvador <osalvador@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      9e59baa2
    • David Hildenbrand's avatar
      mm/memory_hotplug: release memory resource after arch_remove_memory() · 2ad264f6
      David Hildenbrand authored
      commit d9eb1417 upstream.
      
      Patch series "mm/memory_hotplug: Better error handling when removing
      memory", v1.
      
      Error handling when removing memory is somewhat messed up right now.  Some
      errors result in warnings, others are completely ignored.  Memory unplug
      code can essentially not deal with errors properly as of now.
      remove_memory() will never fail.
      
      We have basically two choices:
      1. Allow arch_remov_memory() and friends to fail, propagating errors via
         remove_memory(). Might be problematic (e.g. DIMMs consisting of multiple
         pieces added/removed separately).
      2. Don't allow the functions to fail, handling errors in a nicer way.
      
      It seems like most errors that can theoretically happen are really corner
      cases and mostly theoretical (e.g.  "section not valid").  However e.g.
      aborting removal of sections while all callers simply continue in case of
      errors is not nice.
      
      If we can gurantee that removal of memory always works (and WARN/skip in
      case of theoretical errors so we can figure out what is going on), we can
      go ahead and implement better error handling when adding memory.
      
      E.g. via add_memory():
      
      arch_add_memory()
      ret = do_stuff()
      if (ret) {
      	arch_remove_memory();
      	goto error;
      }
      
      Handling here that arch_remove_memory() might fail is basically
      impossible.  So I suggest, let's avoid reporting errors while removing
      memory, warning on theoretical errors instead and continuing instead of
      aborting.
      
      This patch (of 4):
      
      __add_pages() doesn't add the memory resource, so __remove_pages()
      shouldn't remove it.  Let's factor it out.  Especially as it is a special
      case for memory used as system memory, added via add_memory() and friends.
      
      We now remove the resource after removing the sections instead of doing it
      the other way around.  I don't think this change is problematic.
      
      add_memory()
      	register memory resource
      	arch_add_memory()
      
      remove_memory
      	arch_remove_memory()
      	release memory resource
      
      While at it, explain why we ignore errors and that it only happeny if
      we remove memory in a different granularity as we added it.
      
      [david@redhat.com: fix printk warning]
        Link: http://lkml.kernel.org/r/20190417120204.6997-1-david@redhat.com
      Link: http://lkml.kernel.org/r/20190409100148.24703-2-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Reviewed-by: default avatarOscar Salvador <osalvador@suse.de>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: David Hildenbrand <david@redhat.com>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Wei Yang <richard.weiyang@gmail.com>
      Cc: Qian Cai <cai@lca.pw>
      Cc: Arun KS <arunks@codeaurora.org>
      Cc: Mathieu Malaterre <malat@debian.org>
      Cc: Andrew Banman <andrew.banman@hpe.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Christophe Leroy <christophe.leroy@c-s.fr>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Mike Rapoport <rppt@linux.ibm.com>
      Cc: Mike Travis <mike.travis@hpe.com>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Oscar Salvador <osalvador@suse.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Rob Herring <robh@kernel.org>
      Cc: Stefan Agner <stefan@agner.ch>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      2ad264f6
    • Oscar Salvador's avatar
      mm, memory_hotplug: add nid parameter to arch_remove_memory · 5c1f8f53
      Oscar Salvador authored
      commit 2c2a5af6 upstream.
      
      -- snip --
      
      Missing unification of mm/hmm.c and kernel/memremap.c
      
      -- snip --
      
      Patch series "Do not touch pages in hot-remove path", v2.
      
      This patchset aims for two things:
      
       1) A better definition about offline and hot-remove stage
       2) Solving bugs where we can access non-initialized pages
          during hot-remove operations [2] [3].
      
      This is achieved by moving all page/zone handling to the offline
      stage, so we do not need to access pages when hot-removing memory.
      
      [1] https://patchwork.kernel.org/cover/10691415/
      [2] https://patchwork.kernel.org/patch/10547445/
      [3] https://www.spinics.net/lists/linux-mm/msg161316.html
      
      This patch (of 5):
      
      This is a preparation for the following-up patches.  The idea of passing
      the nid is that it will allow us to get rid of the zone parameter
      afterwards.
      
      Link: http://lkml.kernel.org/r/20181127162005.15833-2-osalvador@suse.deSigned-off-by: default avatarOscar Salvador <osalvador@suse.de>
      Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
      Reviewed-by: default avatarPavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      5c1f8f53
    • Wei Yang's avatar
      drivers/base/memory.c: remove an unnecessary check on NR_MEM_SECTIONS · 4149c869
      Wei Yang authored
      commit 3b6fd6ff upstream.
      
      In cb5e39b8 ("drivers: base: refactor add_memory_section() to
      add_memory_block()"), add_memory_block() is introduced, which is only
      invoked in memory_dev_init().
      
      When combining these two loops in memory_dev_init() and
      add_memory_block(), they looks like this:
      
          for (i = 0; i < NR_MEM_SECTIONS; i += sections_per_block)
              for (j = i;
      	    (j < i + sections_per_block) && j < NR_MEM_SECTIONS;
      	    j++)
      
      Since it is sure the (i < NR_MEM_SECTIONS) and j sits in its own memory
      block, the check of (j < NR_MEM_SECTIONS) is not necessary.
      
      This patch just removes this check.
      
      Link: http://lkml.kernel.org/r/20181123222811.18216-1-richard.weiyang@gmail.comSigned-off-by: default avatarWei Yang <richard.weiyang@gmail.com>
      Reviewed-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Seth Jennings <sjenning@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      4149c869
    • Wei Yang's avatar
      mm, sparse: pass nid instead of pgdat to sparse_add_one_section() · aa2e8b68
      Wei Yang authored
      commit 4e0d2e7e upstream.
      
      Since the information needed in sparse_add_one_section() is node id to
      allocate proper memory, it is not necessary to pass its pgdat.
      
      This patch changes the prototype of sparse_add_one_section() to pass node
      id directly.  This is intended to reduce misleading that
      sparse_add_one_section() would touch pgdat.
      
      Link: http://lkml.kernel.org/r/20181204085657.20472-2-richard.weiyang@gmail.comSigned-off-by: default avatarWei Yang <richard.weiyang@gmail.com>
      Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      aa2e8b68
    • Wei Yang's avatar
      mm, sparse: drop pgdat_resize_lock in sparse_add/remove_one_section() · b1dbaa19
      Wei Yang authored
      commit 83af6588 upstream.
      
      pgdat_resize_lock is used to protect pgdat's memory region information
      like: node_start_pfn, node_present_pages, etc.  While in function
      sparse_add/remove_one_section(), pgdat_resize_lock is used to protect
      initialization/release of one mem_section.  This looks not proper.
      
      These code paths are currently protected by mem_hotplug_lock currently but
      should there ever be any reason for locking at the sparse layer a
      dedicated lock should be introduced.
      
      Following is the current call trace of sparse_add/remove_one_section()
      
          mem_hotplug_begin()
          arch_add_memory()
             add_pages()
                 __add_pages()
                     __add_section()
                         sparse_add_one_section()
          mem_hotplug_done()
      
          mem_hotplug_begin()
          arch_remove_memory()
              __remove_pages()
                  __remove_section()
                      sparse_remove_one_section()
          mem_hotplug_done()
      
      The comment above the pgdat_resize_lock also mentions "Holding this will
      also guarantee that any pfn_valid() stays that way.", which is true with
      the current implementation and false after this patch.  But current
      implementation doesn't meet this comment.  There isn't any pfn walkers to
      take the lock so this looks like a relict from the past.  This patch also
      removes this comment.
      
      [richard.weiyang@gmail.com: v4]
        Link: http://lkml.kernel.org/r/20181204085657.20472-1-richard.weiyang@gmail.com
      [mhocko@suse.com: changelog suggestion]
      Link: http://lkml.kernel.org/r/20181128091243.19249-1-richard.weiyang@gmail.comSigned-off-by: default avatarWei Yang <richard.weiyang@gmail.com>
      Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b1dbaa19