Messages in this thread | | | Date | Tue, 23 Nov 2010 16:26:47 -0500 (EST) | From | Nicolas Pitre <> | Subject | Re: [PATCH] ARM: Fix find_next_zero_bit and related assembly |
| |
On Thu, 11 Nov 2010, James Jones wrote:
> 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. > > Signed-off-by: James Jones <jajones@nvidia.com> > Tested-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Please send to RMK's patch system.
> --- > arch/arm/lib/findbit.S | 6 ++++-- > 1 files changed, 4 insertions(+), 2 deletions(-) > > diff --git a/arch/arm/lib/findbit.S b/arch/arm/lib/findbit.S > index 1e4cbd4..64f6bc1 100644 > --- a/arch/arm/lib/findbit.S > +++ b/arch/arm/lib/findbit.S > @@ -174,8 +174,8 @@ ENDPROC(_find_next_bit_be) > */ > .L_found: > #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 > #endif > + cmp r1, r0 @ Clamp to maxbit > + movlo r0, r1 > mov pc, lr > > -- > 1.7.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >
| |