From: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx> pfn_valid can be wrong when parsing a invalid pfn whose phys address exceeds BITS_PER_LONG as the MSB will be trimed when shifted. Signed-off-by: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx> --- arch/arm/mm/init.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index c2daabb..cc769fa 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -177,6 +177,11 @@ 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) { + phys_addr_t addr = __pfn_to_phys(pfn); + + if (__phys_to_pfn(addr) != pfn) + return 0; + return memblock_is_map_memory(__pfn_to_phys(pfn)); } EXPORT_SYMBOL(pfn_valid); -- 1.9.1