releases/4.14.27/mm-memblock.c-hardcode-the-end_pfn-being-1.patch

From 379b03b7fa05f7db521b7732a52692448a3c34fe Mon Sep 17 00:00:00 2001
From: Daniel Vacek <neelx@redhat.com>
Date: Fri, 9 Mar 2018 15:51:09 -0800
Subject: mm/memblock.c: hardcode the end_pfn being -1

From: Daniel Vacek <neelx@redhat.com>

commit 379b03b7fa05f7db521b7732a52692448a3c34fe upstream.

This is just a cleanup.  It aids handling the special end case in the
next commit.

[akpm@linux-foundation.org: make it work against current -linus, not against -mm]
[akpm@linux-foundation.org: make it work against current -linus, not against -mm some more]
Link: http://lkml.kernel.org/r/1ca478d4269125a99bcfb1ca04d7b88ac1aee924.1520011944.git.neelx@redhat.com
Signed-off-by: Daniel Vacek <neelx@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 mm/memblock.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -1107,7 +1107,7 @@ unsigned long __init_memblock memblock_n
 	struct memblock_type *type = &memblock.memory;
 	unsigned int right = type->cnt;
 	unsigned int mid, left = 0;
-	phys_addr_t addr = PFN_PHYS(pfn + 1);
+	phys_addr_t addr = PFN_PHYS(++pfn);
 
 	do {
 		mid = (right + left) / 2;
@@ -1118,15 +1118,15 @@ unsigned long __init_memblock memblock_n
 				  type->regions[mid].size))
 			left = mid + 1;
 		else {
-			/* addr is within the region, so pfn + 1 is valid */
-			return min(pfn + 1, max_pfn);
+			/* addr is within the region, so pfn is valid */
+			return pfn;
 		}
 	} while (left < right);
 
 	if (right == type->cnt)
-		return max_pfn;
+		return -1UL;
 	else
-		return min(PHYS_PFN(type->regions[right].base), max_pfn);
+		return PHYS_PFN(type->regions[right].base);
 }
 
 /**