The patch titled
Subject: mm: fix phys_to_target_node() and memory_add_physaddr_to_nid() exports
has been added to the -mm tree. Its filename is
mm-fix-phys_to_target_node-and-memory_add_physaddr_to_nid-exports.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-fix-phys_to_target_node-and-memory_add_physaddr_to_nid-exports.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-fix-phys_to_target_node-and-memory_add_physaddr_to_nid-exports.patch
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------------------------------------------------------
From: Dan Williams <dan.j.williams@xxxxxxxxx>
Subject: mm: fix phys_to_target_node() and memory_add_physaddr_to_nid() exports
The core-mm has a default __weak implementation of phys_to_target_node()
to mirror the weak definition of memory_add_physaddr_to_nid(). That
symbol is exported for modules. However, while the export in
mm/memory_hotplug.c exported the symbol in the configuration cases of:
CONFIG_NUMA_KEEP_MEMINFO=y
CONFIG_MEMORY_HOTPLUG=y
...and:
CONFIG_NUMA_KEEP_MEMINFO=n
CONFIG_MEMORY_HOTPLUG=y
...it failed to export the symbol in the case of:
CONFIG_NUMA_KEEP_MEMINFO=y
CONFIG_MEMORY_HOTPLUG=n
Not only is that broken, but Christoph points out that the kernel should
not be exporting any __weak symbol, which means that
memory_add_physaddr_to_nid() example that phys_to_target_node() copied is
broken too.
Rework the definition of phys_to_target_node() and
memory_add_physaddr_to_nid() to not require weak symbols. Move to the
common arch override design-pattern of an asm header defining a symbol to
replace the default implementation.
The only common header that all memory_add_physaddr_to_nid() producing
architectures implement is asm/sparsemem.h. In fact, powerpc already
defines its memory_add_physaddr_to_nid() helper in sparsemem.h.
Double-down on that observation and define phys_to_target_node() where
necessary in asm/sparsemem.h. An alternate consideration that was
discarded was to put this override in asm/numa.h, but that entangles with
the definition of MAX_NUMNODES relative to the inclusion of
linux/nodemask.h, and requires powerpc to grow a new header.
The dependency on NUMA_KEEP_MEMINFO for DEV_DAX_HMEM_DEVICES is invalid
now that the symbol is properly exported / stubbed in all combinations of
CONFIG_NUMA_KEEP_MEMINFO and CONFIG_MEMORY_HOTPLUG.
Link: https://lkml.kernel.org/r/160447639846.1133764.7044090803980177548.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: a035b6bf863e ("mm/memory_hotplug: introduce default phys_to_target_node() implementation")
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Tested-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Reported-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Tested-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Cc: Joao Martins <joao.m.martins@xxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/ia64/include/asm/sparsemem.h | 6 +++++
arch/powerpc/include/asm/sparsemem.h | 3 +-
arch/x86/include/asm/sparsemem.h | 10 ++++++++
arch/x86/mm/numa.c | 2 +
drivers/dax/Kconfig | 1
include/linux/memory_hotplug.h | 14 -----------
include/linux/numa.h | 30 ++++++++++++++++++++++++-
mm/memory_hotplug.c | 18 ---------------
8 files changed, 49 insertions(+), 35 deletions(-)
--- a/arch/ia64/include/asm/sparsemem.h~mm-fix-phys_to_target_node-and-memory_add_physaddr_to_nid-exports
+++ a/arch/ia64/include/asm/sparsemem.h
@@ -18,4 +18,10 @@
#endif
#endif /* CONFIG_SPARSEMEM */
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+int memory_add_physaddr_to_nid(u64 addr);
+#define memory_add_physaddr_to_nid memory_add_physaddr_to_nid
+#endif
+
#endif /* _ASM_IA64_SPARSEMEM_H */
--- a/arch/powerpc/include/asm/sparsemem.h~mm-fix-phys_to_target_node-and-memory_add_physaddr_to_nid-exports
+++ a/arch/powerpc/include/asm/sparsemem.h
@@ -16,6 +16,8 @@
extern int create_section_mapping(unsigned long start, unsigned long end,
int nid, pgprot_t prot);
extern int remove_section_mapping(unsigned long start, unsigned long end);
+extern int memory_add_physaddr_to_nid(u64 start);
+#define memory_add_physaddr_to_nid memory_add_physaddr_to_nid
#ifdef CONFIG_NUMA
extern int hot_add_scn_to_nid(unsigned long scn_addr);
@@ -26,6 +28,5 @@ static inline int hot_add_scn_to_nid(uns
}
#endif /* CONFIG_NUMA */
#endif /* CONFIG_MEMORY_HOTPLUG */
-
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_SPARSEMEM_H */
--- a/arch/x86/include/asm/sparsemem.h~mm-fix-phys_to_target_node-and-memory_add_physaddr_to_nid-exports
+++ a/arch/x86/include/asm/sparsemem.h
@@ -28,4 +28,14 @@
#endif
#endif /* CONFIG_SPARSEMEM */
+
+#ifndef __ASSEMBLY__
+#ifdef CONFIG_NUMA_KEEP_MEMINFO
+extern int phys_to_target_node(phys_addr_t start);
+#define phys_to_target_node phys_to_target_node
+extern int memory_add_physaddr_to_nid(u64 start);
+#define memory_add_physaddr_to_nid memory_add_physaddr_to_nid
+#endif
+#endif /* __ASSEMBLY__ */
+
#endif /* _ASM_X86_SPARSEMEM_H */
--- a/arch/x86/mm/numa.c~mm-fix-phys_to_target_node-and-memory_add_physaddr_to_nid-exports
+++ a/arch/x86/mm/numa.c
@@ -938,6 +938,7 @@ int phys_to_target_node(phys_addr_t star
return meminfo_to_nid(&numa_reserved_meminfo, start);
}
+EXPORT_SYMBOL_GPL(phys_to_target_node);
int memory_add_physaddr_to_nid(u64 start)
{
@@ -947,4 +948,5 @@ int memory_add_physaddr_to_nid(u64 start
nid = numa_meminfo.blk[0].nid;
return nid;
}
+EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
#endif
--- a/drivers/dax/Kconfig~mm-fix-phys_to_target_node-and-memory_add_physaddr_to_nid-exports
+++ a/drivers/dax/Kconfig
@@ -50,7 +50,6 @@ config DEV_DAX_HMEM
Say M if unsure.
config DEV_DAX_HMEM_DEVICES
- depends on NUMA_KEEP_MEMINFO # for phys_to_target_node()
depends on DEV_DAX_HMEM && DAX=y
def_bool y
--- a/include/linux/memory_hotplug.h~mm-fix-phys_to_target_node-and-memory_add_physaddr_to_nid-exports
+++ a/include/linux/memory_hotplug.h
@@ -281,20 +281,6 @@ static inline bool movable_node_is_enabl
}
#endif /* ! CONFIG_MEMORY_HOTPLUG */
-#ifdef CONFIG_NUMA
-extern int memory_add_physaddr_to_nid(u64 start);
-extern int phys_to_target_node(u64 start);
-#else
-static inline int memory_add_physaddr_to_nid(u64 start)
-{
- return 0;
-}
-static inline int phys_to_target_node(u64 start)
-{
- return 0;
-}
-#endif
-
#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
/*
* pgdat resizing functions
--- a/include/linux/numa.h~mm-fix-phys_to_target_node-and-memory_add_physaddr_to_nid-exports
+++ a/include/linux/numa.h
@@ -21,13 +21,41 @@
#endif
#ifdef CONFIG_NUMA
+#include <linux/printk.h>
+#include <asm/sparsemem.h>
+
/* Generic implementation available */
int numa_map_to_online_node(int node);
-#else
+
+#ifndef memory_add_physaddr_to_nid
+static inline int memory_add_physaddr_to_nid(u64 start)
+{
+ pr_info_once("Unknown online node for memory at 0x%llx, assuming node 0\n",
+ start);
+ return 0;
+}
+#endif
+#ifndef phys_to_target_node
+static inline int phys_to_target_node(u64 start)
+{
+ pr_info_once("Unknown target node for memory at 0x%llx, assuming node 0\n",
+ start);
+ return 0;
+}
+#endif
+#else /* !CONFIG_NUMA */
static inline int numa_map_to_online_node(int node)
{
return NUMA_NO_NODE;
}
+static inline int memory_add_physaddr_to_nid(u64 start)
+{
+ return 0;
+}
+static inline int phys_to_target_node(u64 start)
+{
+ return 0;
+}
#endif
#endif /* _LINUX_NUMA_H */
--- a/mm/memory_hotplug.c~mm-fix-phys_to_target_node-and-memory_add_physaddr_to_nid-exports
+++ a/mm/memory_hotplug.c
@@ -350,24 +350,6 @@ int __ref __add_pages(int nid, unsigned
return err;
}
-#ifdef CONFIG_NUMA
-int __weak memory_add_physaddr_to_nid(u64 start)
-{
- pr_info_once("Unknown online node for memory at 0x%llx, assuming node 0\n",
- start);
- return 0;
-}
-EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
-
-int __weak phys_to_target_node(u64 start)
-{
- pr_info_once("Unknown target node for memory at 0x%llx, assuming node 0\n",
- start);
- return 0;
-}
-EXPORT_SYMBOL_GPL(phys_to_target_node);
-#endif
-
/* find the smallest valid pfn in the range [start_pfn, end_pfn) */
static unsigned long find_smallest_section_pfn(int nid, struct zone *zone,
unsigned long start_pfn,
_
Patches currently in -mm which might be from dan.j.williams@xxxxxxxxx are
mm-fix-phys_to_target_node-and-memory_add_physaddr_to_nid-exports.patch
device-dax-kmem-use-struct_size.patch
xen-unpopulated-alloc-consolidate-pgmap-manipulation.patch
