This commit fixes the problem for the kernel
with CONFIG_SPARSEMEM=y and CONFIG_HAVE_ARCH_PFN_VALID=y.
VM subsystem insists that memmap entries within the align to MAX_ORDER_NR_PAGES
must exist and be initialized.
However, in the kernel with CONFIG_SPARSEMEM=y and CONFIG_HAVE_ARCH_PFN_VALID=y,
the kernel only initializes the entries corresponding to the memory regions
specified by "mem=" options. This causes "kernel BUG at mm/page_alloc.c:777!"
This BUG message comes from the following BUG_ON() line in move_freepages().
BUG_ON(page_zone(start_page) != page_zone(end_page));
Signed-off-by: Akira Takeuchi <takeuchi.akr@xxxxxxxxxxxxxxxx>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@xxxxxxxxxxxxxxxx>
---
include/linux/mmzone.h | 8 +++++---
1 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index dff7115..1b7538c 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -1088,13 +1088,15 @@ static inline struct mem_section *__pfn_to_section(unsigned long pfn)
return __nr_to_section(pfn_to_section_nr(pfn));
}
-#ifndef CONFIG_HAVE_ARCH_PFN_VALID
-static inline int pfn_valid(unsigned long pfn)
+static inline int sparsemem_pfn_valid(unsigned long pfn)
{
if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
return 0;
return valid_section(__nr_to_section(pfn_to_section_nr(pfn)));
}
+
+#ifndef CONFIG_HAVE_ARCH_PFN_VALID
+#define pfn_valid(pfn) sparsemem_pfn_valid(pfn)
#endif
static inline int pfn_present(unsigned long pfn)
@@ -1119,7 +1121,7 @@ static inline int pfn_present(unsigned long pfn)
#define pfn_to_nid(pfn) (0)
#endif
-#define early_pfn_valid(pfn) pfn_valid(pfn)
+#define early_pfn_valid(pfn) sparsemem_pfn_valid(pfn)
void sparse_init(void);
#else
#define sparse_init() do {} while (0)
--
1.7.4.1
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>