The patch titled
Subject: mm/memory_hotplug: handle memblock_add_node() failures in add_memory_resource()
has been added to the -mm tree. Its filename is
mm-memory_hotplug-handle-memblock_add_node-failures-in-add_memory_resource.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-memory_hotplug-handle-memblock_add_node-failures-in-add_memory_resource.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-memory_hotplug-handle-memblock_add_node-failures-in-add_memory_resource.patch
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------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: mm/memory_hotplug: handle memblock_add_node() failures in add_memory_resource()
Patch series "mm/memory_hotplug: full support for add_memory_driver_managed() with CONFIG_ARCH_KEEP_MEMBLOCK", v2.
Architectures that require CONFIG_ARCH_KEEP_MEMBLOCK=y, such as arm64,
don't cleanly support add_memory_driver_managed() yet. Most prominently,
kexec_file can still end up placing kexec images on such driver-managed
memory, resulting in undesired behavior, for example, having kexec images
located on memory not part of the firmware-provided memory map.
Teaching kexec to not place images on driver-managed memory is especially
relevant for virtio-mem. Details can be found in commit 7b7b27214bba
("mm/memory_hotplug: introduce add_memory_driver_managed()").
Extend memblock with a new flag and set it from memory hotplug code when
applicable. This is required to fully support virtio-mem on arm64, making
also kexec_file behave like on x86-64.
This patch (of 2):
If memblock_add_node() fails, we're most probably running out of memory.
While this is unlikely to happen, it can happen and having memory added
without a memblock can be problematic for architectures that use memblock
to detect valid memory. Let's fail in a nice way instead of silently
ignoring the error.
Link: https://lkml.kernel.org/r/20211004093605.5830-1-david@xxxxxxxxxx
Link: https://lkml.kernel.org/r/20211004093605.5830-2-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Jianyong Wu <Jianyong.Wu@xxxxxxx>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@xxxxxxxxxxxxx>
Cc: Vineet Gupta <vgupta@xxxxxxxxxx>
Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Cc: Huacai Chen <chenhuacai@xxxxxxxxxx>
Cc: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Cc: Heiko Carstens <hca@xxxxxxxxxxxxx>
Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Cc: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Cc: Eric Biederman <ebiederm@xxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Shahab Vahedi <shahab@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memory_hotplug.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
--- a/mm/memory_hotplug.c~mm-memory_hotplug-handle-memblock_add_node-failures-in-add_memory_resource
+++ a/mm/memory_hotplug.c
@@ -1369,8 +1369,11 @@ int __ref add_memory_resource(int nid, s
mem_hotplug_begin();
- if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK))
- memblock_add_node(start, size, nid);
+ if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK)) {
+ ret = memblock_add_node(start, size, nid);
+ if (ret)
+ goto error_mem_hotplug_end;
+ }
ret = __try_online_node(nid, false);
if (ret < 0)
@@ -1443,6 +1446,7 @@ error:
rollback_node_hotadd(nid);
if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK))
memblock_remove(start, size);
+error_mem_hotplug_end:
mem_hotplug_done();
return ret;
}
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
memory-hotplugrst-fix-two-instances-of-movablecore-that-should-be-movable_node.patch
memory-hotplugrst-fix-wrong-sys-module-memory_hotplug-parameters-path.patch
memory-hotplugrst-document-the-auto-movable-online-policy.patch
mm-memory_hotplug-remove-config_x86_64_acpi_numa-dependency-from-config_memory_hotplug.patch
mm-memory_hotplug-remove-config_memory_hotplug_sparse.patch
mm-memory_hotplug-restrict-config_memory_hotplug-to-64-bit.patch
mm-memory_hotplug-remove-highmem-leftovers.patch
mm-memory_hotplug-remove-stale-function-declarations.patch
x86-remove-memory-hotplug-support-on-x86_32.patch
mm-memory_hotplug-handle-memblock_add_node-failures-in-add_memory_resource.patch
memblock-improve-memblock_hotplug-documentation.patch
memblock-allow-to-specify-flags-with-memblock_add_node.patch
memblock-add-memblock_driver_managed-to-mimic-ioresource_sysram_driver_managed.patch
mm-memory_hotplug-indicate-memblock_driver_managed-with-ioresource_sysram_driver_managed.patch
x86-xen-update-xen_oldmem_pfn_is_ram-documentation.patch
x86-xen-simplify-xen_oldmem_pfn_is_ram.patch
x86-xen-print-a-warning-when-hvmop_get_mem_type-fails.patch
proc-vmcore-let-pfn_is_ram-return-a-bool.patch
proc-vmcore-convert-oldmem_pfn_is_ram-callback-to-more-generic-vmcore-callbacks.patch
virtio-mem-factor-out-hotplug-specifics-from-virtio_mem_init-into-virtio_mem_init_hotplug.patch
virtio-mem-factor-out-hotplug-specifics-from-virtio_mem_probe-into-virtio_mem_init_hotplug.patch
virtio-mem-factor-out-hotplug-specifics-from-virtio_mem_remove-into-virtio_mem_deinit_hotplug.patch
virtio-mem-kdump-mode-to-sanitize-proc-vmcore-access.patch
kernel-resource-clean-up-and-optimize-iomem_is_exclusive.patch
kernel-resource-disallow-access-to-exclusive-system-ram-regions.patch
virtio-mem-disallow-mapping-virtio-mem-memory-via-dev-mem.patch
