[PATCH] arch : arm : add a criteria for pfn_valid

From: Zhaoyang Huang
Date: Fri Aug 16 2019 - 23:00:52 EST


From: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx>

pfn_valid can be wrong while the MSB of physical address be trimed as pfn
larger than the max_pfn.

Signed-off-by: Zhaoyang Huang <huangzhaoyang@xxxxxxxxx>
---
arch/arm/mm/init.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index c2daabb..9c4d938 100644
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -177,7 +177,8 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max_low,
#ifdef CONFIG_HAVE_ARCH_PFN_VALID
int pfn_valid(unsigned long pfn)
{
- return memblock_is_map_memory(__pfn_to_phys(pfn));
+ return (pfn > max_pfn) ?
+ false : memblock_is_map_memory(__pfn_to_phys(pfn));
}
EXPORT_SYMBOL(pfn_valid);
#endif
--
1.9.1