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a927bd6ba9
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.
[dan.j.williams@intel.com: v4]
Link: https://lkml.kernel.org/r/160461461867.1505359.5301571728749534585.stgit@dwillia2-desk3.amr.corp.intel.com
[dan.j.williams@intel.com: powerpc: fix create_section_mapping compile warning]
Link: https://lkml.kernel.org/r/160558386174.2948926.2740149041249041764.stgit@dwillia2-desk3.amr.corp.intel.com
Fixes: a035b6bf86 ("mm/memory_hotplug: introduce default phys_to_target_node() implementation")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lkml.kernel.org/r/160447639846.1133764.7044090803980177548.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
41 lines
1.1 KiB
C
41 lines
1.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _ASM_X86_SPARSEMEM_H
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#define _ASM_X86_SPARSEMEM_H
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#ifdef CONFIG_SPARSEMEM
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/*
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* generic non-linear memory support:
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*
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* 1) we will not split memory into more chunks than will fit into the flags
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* field of the struct page
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*
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* SECTION_SIZE_BITS 2^n: size of each section
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* MAX_PHYSMEM_BITS 2^n: max size of physical address space
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*
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*/
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#ifdef CONFIG_X86_32
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# ifdef CONFIG_X86_PAE
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# define SECTION_SIZE_BITS 29
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# define MAX_PHYSMEM_BITS 36
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# else
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# define SECTION_SIZE_BITS 26
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# define MAX_PHYSMEM_BITS 32
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# endif
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#else /* CONFIG_X86_32 */
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# define SECTION_SIZE_BITS 27 /* matt - 128 is convenient right now */
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# define MAX_PHYSMEM_BITS (pgtable_l5_enabled() ? 52 : 46)
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#endif
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#endif /* CONFIG_SPARSEMEM */
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#ifndef __ASSEMBLY__
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#ifdef CONFIG_NUMA_KEEP_MEMINFO
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extern int phys_to_target_node(phys_addr_t start);
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#define phys_to_target_node phys_to_target_node
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extern int memory_add_physaddr_to_nid(u64 start);
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#define memory_add_physaddr_to_nid memory_add_physaddr_to_nid
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#endif
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#endif /* __ASSEMBLY__ */
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#endif /* _ASM_X86_SPARSEMEM_H */
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