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authorDan Williams <dan.j.williams@intel.com>2016-01-15 16:56:17 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-01-15 17:56:32 -0800
commit260ae3f7db614a5c4aa4b773599f99adc1d9859e (patch)
treefaeb0c28acb29ff347f9416ae207e739117cb9a0
parent34c0fd540e79fb49ef9ce864dae1058cca265780 (diff)
downloadlinux-260ae3f7db614a5c4aa4b773599f99adc1d9859e.tar.bz2
mm: skip memory block registration for ZONE_DEVICE
Prevent userspace from trying and failing to online ZONE_DEVICE pages which are meant to never be onlined. For example on platforms with a udev rule like the following: SUBSYSTEM=="memory", ACTION=="add", ATTR{state}=="offline", ATTR{state}="online" ...will generate futile attempts to online the ZONE_DEVICE sections. Example kernel messages: Built 1 zonelists in Node order, mobility grouping on. Total pages: 1004747 Policy zone: Normal online_pages [mem 0x248000000-0x24fffffff] failed Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--drivers/base/memory.c13
-rw-r--r--include/linux/mm.h12
2 files changed, 25 insertions, 0 deletions
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 619fe584a44c..213456c2b123 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -647,6 +647,13 @@ static int add_memory_block(int base_section_nr)
return 0;
}
+static bool is_zone_device_section(struct mem_section *ms)
+{
+ struct page *page;
+
+ page = sparse_decode_mem_map(ms->section_mem_map, __section_nr(ms));
+ return is_zone_device_page(page);
+}
/*
* need an interface for the VM to add new memory regions,
@@ -657,6 +664,9 @@ int register_new_memory(int nid, struct mem_section *section)
int ret = 0;
struct memory_block *mem;
+ if (is_zone_device_section(section))
+ return 0;
+
mutex_lock(&mem_sysfs_mutex);
mem = find_memory_block(section);
@@ -693,6 +703,9 @@ static int remove_memory_section(unsigned long node_id,
{
struct memory_block *mem;
+ if (is_zone_device_section(section))
+ return 0;
+
mutex_lock(&mem_sysfs_mutex);
mem = find_memory_block(section);
unregister_mem_sect_under_nodes(mem, __section_nr(section));
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 0ef5f21735af..d9fe12d45c21 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -674,6 +674,18 @@ static inline enum zone_type page_zonenum(const struct page *page)
return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK;
}
+#ifdef CONFIG_ZONE_DEVICE
+static inline bool is_zone_device_page(const struct page *page)
+{
+ return page_zonenum(page) == ZONE_DEVICE;
+}
+#else
+static inline bool is_zone_device_page(const struct page *page)
+{
+ return false;
+}
+#endif
+
#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
#define SECTION_IN_PAGE_FLAGS
#endif