From: Vladimir Murzin <vladimir.murzin@arm.com>
Date: Tue, 19 Apr 2016 11:35:55 +0000 (+0100)
Subject: ARM: 8564/1: fix cpu feature extracting helper
X-Git-Tag: v4.9.8~1945^2~4
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=ac36a881b72a1e9831f1c59abf935868c90685cf;p=platform%2Fkernel%2Flinux-rpi3.git

ARM: 8564/1: fix cpu feature extracting helper

Commit b8c9592 "ARM: 8318/1: treat CPU feature register fields as signed
quantities" introduced helper to extract signed quantities of 4-bit
blocks. However, with a current code feature with value 0b1000 isn't
rejected as negative. So fix the "if" condition.

Reported-by: Jonathan Brawn <Jon.Brawn@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---

diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
index b23c6c8..1ee94c7 100644
--- a/arch/arm/include/asm/cputype.h
+++ b/arch/arm/include/asm/cputype.h
@@ -276,7 +276,7 @@ static inline int __attribute_const__ cpuid_feature_extract_field(u32 features,
 	int feature = (features >> field) & 15;
 
 	/* feature registers are signed values */
-	if (feature > 8)
+	if (feature > 7)
 		feature -= 16;
 
 	return feature;