From bfe63d3beabfac93521c8b7ccd40befd7a90148e Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Thu, 6 Jul 2017 15:37:42 -0700 Subject: [PATCH] mm: drop page_initialized check from get_nid_for_pfn Commit c04fc586c1a4 ("mm: show node to memory section relationship with symlinks in sysfs") has added means to export memblock<->node association into the sysfs. It has also introduced get_nid_for_pfn which is a rather confusing counterpart of pfn_to_nid which checks also whether the pfn page is already initialized (page_initialized). This is done by checking page::lru != NULL which doesn't make any sense at all. Nothing in this path really relies on the lru list being used or initialized. Just remove it because this will become a problem with later patches. Thanks to Reza Arbab for testing which revealed this to be a problem (http://lkml.kernel.org/r/20170403202337.GA12482@dhcp22.suse.cz) Link: http://lkml.kernel.org/r/20170515085827.16474-4-mhocko@kernel.org Signed-off-by: Michal Hocko Acked-by: Vlastimil Babka Cc: Reza Arbab Cc: Andi Kleen Cc: Andrea Arcangeli Cc: Balbir Singh Cc: Dan Williams Cc: Daniel Kiper Cc: David Rientjes Cc: Heiko Carstens Cc: Igor Mammedov Cc: Jerome Glisse Cc: Joonsoo Kim Cc: Martin Schwidefsky Cc: Mel Gorman Cc: Tobias Regnery Cc: Toshi Kani Cc: Vitaly Kuznetsov Cc: Xishi Qiu Cc: Yasuaki Ishimatsu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/base/node.c | 7 ------- 1 file changed, 7 deletions(-) diff --git a/drivers/base/node.c b/drivers/base/node.c index 0440d95c9b5b..db769d3148b7 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -368,21 +368,14 @@ int unregister_cpu_under_node(unsigned int cpu, unsigned int nid) } #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE -#define page_initialized(page) (page->lru.next) - static int __ref get_nid_for_pfn(unsigned long pfn) { - struct page *page; - if (!pfn_valid_within(pfn)) return -1; #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT if (system_state < SYSTEM_RUNNING) return early_pfn_to_nid(pfn); #endif - page = pfn_to_page(pfn); - if (!page_initialized(page)) - return -1; return pfn_to_nid(pfn); } -- 2.39.2