From 54a75157d97976f35e63e37e31e39bda622cbf39 Mon Sep 17 00:00:00 2001
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Date: Thu, 6 Aug 2020 23:19:48 -0700
Subject: [PATCH] mm/debug: print hashed address of struct page

The actual address of the struct page isn't particularly helpful, while
the hashed address helps match with other messages elsewhere.  Add the PFN
that the page refers to in order to help diagnose problems where the page
is improperly aligned for the purpose.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: William Kucharski <william.kucharski@oracle.com>
Link: http://lkml.kernel.org/r/20200709202117.7216-7-willy@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 mm/debug.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/mm/debug.c b/mm/debug.c
index c4dbe4def83da..8f569db9a5146 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -95,17 +95,17 @@ void __dump_page(struct page *page, const char *reason)
 	 */
 	mapcount = PageSlab(head) ? 0 : page_mapcount(page);
 
-	pr_warn("page:%px refcount:%d mapcount:%d mapping:%p index:%#lx\n",
+	pr_warn("page:%p refcount:%d mapcount:%d mapping:%p index:%#lx pfn:%#lx\n",
 			page, page_ref_count(head), mapcount, mapping,
-			page_to_pgoff(page));
+			page_to_pgoff(page), page_to_pfn(page));
 	if (compound) {
 		if (hpage_pincount_available(page)) {
-			pr_warn("head:%px order:%u compound_mapcount:%d compound_pincount:%d\n",
+			pr_warn("head:%p order:%u compound_mapcount:%d compound_pincount:%d\n",
 					head, compound_order(head),
 					compound_mapcount(head),
 					compound_pincount(head));
 		} else {
-			pr_warn("head:%px order:%u compound_mapcount:%d\n",
+			pr_warn("head:%p order:%u compound_mapcount:%d\n",
 					head, compound_order(head),
 					compound_mapcount(head));
 		}
-- 
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