path: root/arch/arm/lib
diff options
authorJames Jones <jajones@nvidia.com>2010-11-24 00:21:37 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2010-11-24 20:17:46 +0000
commit0e91ec0c06d2cd15071a6021c94840a50e6671aa (patch)
tree1d0cb8bbdbab498af1f2513d9f0637105b2d2c3b /arch/arm/lib
parent28c22d7dc99486ef4186dde41d5260e75b3076f7 (diff)
ARM: 6482/2: Fix find_next_zero_bit and related assembly
The find_next_bit, find_first_bit, find_next_zero_bit and find_first_zero_bit functions were not properly clamping to the maxbit argument at the bit level. They were instead only checking maxbit at the byte level. To fix this, add a compare and a conditional move instruction to the end of the common bit-within-the- byte code used by all the functions and be sure not to clobber the maxbit argument before it is used. Cc: <stable@kernel.org> Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org> Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: James Jones <jajones@nvidia.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/lib')
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/arm/lib/findbit.S b/arch/arm/lib/findbit.S
index 1e4cbd4e7be9..64f6bc1a9132 100644
--- a/arch/arm/lib/findbit.S
+++ b/arch/arm/lib/findbit.S
@@ -174,8 +174,8 @@ ENDPROC(_find_next_bit_be)
#if __LINUX_ARM_ARCH__ >= 5
- rsb r1, r3, #0
- and r3, r3, r1
+ rsb r0, r3, #0
+ and r3, r3, r0
clz r3, r3
rsb r3, r3, #31
add r0, r2, r3
@@ -190,5 +190,7 @@ ENDPROC(_find_next_bit_be)
addeq r2, r2, #1
mov r0, r2
+ cmp r1, r0 @ Clamp to maxbit
+ movlo r0, r1
mov pc, lr