From 3c424f359898aff48c3d5bed608ac706f8a528c3 Mon Sep 17 00:00:00 2001
From: Pawel Moll <pawel.moll@arm.com>
Date: Thu, 26 Jan 2012 11:47:11 +0100
Subject: [PATCH] ARM: 7304/1: ioremap: fix boundary check when reusing static
 mapping

Since commit 576d2f2525612ecb5af029a76f21f22a3b82563d "ARM: add
generic ioremap optimization by reusing static mappings" ioremap()
is trying to reuse existing static mapping when possible.

The condition checking boundaries of the requested and existing
mappings didn't take in-page offset into consideration though,
which lead to obscure and hard to debug problems when requested
mapping crossed end of the static one.

Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
 arch/arm/mm/ioremap.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
index 80632e8d7538f..ba159370fa5f7 100644
--- a/arch/arm/mm/ioremap.c
+++ b/arch/arm/mm/ioremap.c
@@ -225,7 +225,8 @@ void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn,
 		if ((area->flags & VM_ARM_MTYPE_MASK) != VM_ARM_MTYPE(mtype))
 			continue;
 		if (__phys_to_pfn(area->phys_addr) > pfn ||
-		    __pfn_to_phys(pfn) + size-1 > area->phys_addr + area->size-1)
+		    __pfn_to_phys(pfn) + offset + size-1 >
+		    area->phys_addr + area->size-1)
 			continue;
 		/* we can drop the lock here as we know *area is static */
 		read_unlock(&vmlist_lock);
-- 
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