mm/sparsemem: Fix ARM64 boot crash when CONFIG_SPARSEMEM_EXTREME=y

commit 629a359bdb0e0652a8227b4ff3125431995fec6e upstream.

Since commit:

  83e3c48729d9 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y")

we allocate the mem_section array dynamically in sparse_memory_present_with_active_regions(),
but some architectures, like arm64, don't call the routine to initialize sparsemem.

Let's move the initialization into memory_present() it should cover all
architectures.

Reported-and-tested-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Fixes: 83e3c48729d9 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y")
Link: http://lkml.kernel.org/r/20171107083337.89952-1-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Dan Rue <dan.rue@linaro.org>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 02cf30bd01cd9da0de99a34d2b76e27444f1ee51..d51c2087c498c63f3f515d2931e42b5110efb62f 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5651,16 +5651,6 @@ void __init sparse_memory_present_with_active_regions(int nid)
        unsigned long start_pfn, end_pfn;
        int i, this_nid;
 
-#ifdef CONFIG_SPARSEMEM_EXTREME
-       if (!mem_section) {
-               unsigned long size, align;
-
-               size = sizeof(struct mem_section) * NR_SECTION_ROOTS;
-               align = 1 << (INTERNODE_CACHE_SHIFT);
-               mem_section = memblock_virt_alloc(size, align);
-       }
-#endif
-
        for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid)
                memory_present(this_nid, start_pfn, end_pfn);
 }

diff --git a/mm/sparse.c b/mm/sparse.c
index 044138852bafce91f01bf0e8a96cc7b05f02308d..60805abf98af71e53775c00bd2a5975b7f13e6fa 100644 (file)
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -207,6 +207,16 @@ void __init memory_present(int nid, unsigned long start, unsigned long end)
 {
        unsigned long pfn;
 
+#ifdef CONFIG_SPARSEMEM_EXTREME
+       if (unlikely(!mem_section)) {
+               unsigned long size, align;
+
+               size = sizeof(struct mem_section) * NR_SECTION_ROOTS;
+               align = 1 << (INTERNODE_CACHE_SHIFT);
+               mem_section = memblock_virt_alloc(size, align);
+       }
+#endif
+
        start &= PAGE_SECTION_MASK;
        mminit_validate_memmodel_limits(&start, &end);
        for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {