From: Steven Capper <steve.capper@linaro.org>
Date: Mon, 16 Dec 2013 16:25:52 +0000 (+0100)
Subject: ARM: 7923/1: mm: fix dcache flush logic for compound high pages
X-Git-Tag: v3.12.8~28
X-Git-Url: https://git.fsl.cs.sunysb.edu/?a=commitdiff_plain;h=8c3d0f1f021aca05e1ba4ff47c7231c2d7ef95fe;p=unionfs-2.6.39.y.git

ARM: 7923/1: mm: fix dcache flush logic for compound high pages

commit 2a7cfcbc0553365d75716f69ee7b704cac7c9248 upstream.

When given a compound high page, __flush_dcache_page will only flush
the first page of the compound page repeatedly rather than the entire
set of constituent pages.

This error was introduced by:
   0b19f93 ARM: mm: Add support for flushing HugeTLB pages.

This patch corrects the logic such that all constituent pages are now
flushed.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index 6d5ba9afb16..3387e60e4ea 100644
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -175,16 +175,16 @@ void __flush_dcache_page(struct address_space *mapping, struct page *page)
 		unsigned long i;
 		if (cache_is_vipt_nonaliasing()) {
 			for (i = 0; i < (1 << compound_order(page)); i++) {
-				void *addr = kmap_atomic(page);
+				void *addr = kmap_atomic(page + i);
 				__cpuc_flush_dcache_area(addr, PAGE_SIZE);
 				kunmap_atomic(addr);
 			}
 		} else {
 			for (i = 0; i < (1 << compound_order(page)); i++) {
-				void *addr = kmap_high_get(page);
+				void *addr = kmap_high_get(page + i);
 				if (addr) {
 					__cpuc_flush_dcache_area(addr, PAGE_SIZE);
-					kunmap_high(page);
+					kunmap_high(page + i);
 				}
 			}
 		}