Building the kernel with CONFIG_THUMB2_KERNEL=y and
CONFIG_CRYPTO_SPECK_NEON set fails with the following errors:
arch/arm/crypto/speck-neon-core.S: Assembler messages:
arch/arm/crypto/speck-neon-core.S:419: Error: r13 not allowed here -- `bic sp,#0xf'
arch/arm/crypto/speck-neon-core.S:423: Error: r13 not allowed here -- `bic sp,#0xf'
arch/arm/crypto/speck-neon-core.S:427: Error: r13 not allowed here -- `bic sp,#0xf'
arch/arm/crypto/speck-neon-core.S:431: Error: r13 not allowed here -- `bic sp,#0xf'
The problem is that the 'bic' instruction can't operate on the 'sp'
register in Thumb2 mode. Fix it by using a temporary register. This
isn't in the main loop, so the performance difference is negligible.
This also matches what aes-neonbs-core.S does.
Reported-by: Stefan Agner <[email protected]>
Fixes: ede9622162fa ("crypto: arm/speck - add NEON-accelerated implementation of Speck-XTS")
Signed-off-by: Eric Biggers <[email protected]>
---
arch/arm/crypto/speck-neon-core.S | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/arch/arm/crypto/speck-neon-core.S b/arch/arm/crypto/speck-neon-core.S
index 3c1e203e53b9..57caa742016e 100644
--- a/arch/arm/crypto/speck-neon-core.S
+++ b/arch/arm/crypto/speck-neon-core.S
@@ -272,9 +272,11 @@
* Allocate stack space to store 128 bytes worth of tweaks. For
* performance, this space is aligned to a 16-byte boundary so that we
* can use the load/store instructions that declare 16-byte alignment.
+ * For Thumb2 compatibility, don't do the 'bic' directly on 'sp'.
*/
- sub sp, #128
- bic sp, #0xf
+ sub r12, sp, #128
+ bic r12, #0xf
+ mov sp, r12
.if \n == 64
// Load first tweak
--
2.18.0.rc1.244.gcf134e6275-goog
On 19 June 2018 at 00:33, Eric Biggers <[email protected]> wrote:
> Building the kernel with CONFIG_THUMB2_KERNEL=y and
> CONFIG_CRYPTO_SPECK_NEON set fails with the following errors:
>
> arch/arm/crypto/speck-neon-core.S: Assembler messages:
>
> arch/arm/crypto/speck-neon-core.S:419: Error: r13 not allowed here -- `bic sp,#0xf'
> arch/arm/crypto/speck-neon-core.S:423: Error: r13 not allowed here -- `bic sp,#0xf'
> arch/arm/crypto/speck-neon-core.S:427: Error: r13 not allowed here -- `bic sp,#0xf'
> arch/arm/crypto/speck-neon-core.S:431: Error: r13 not allowed here -- `bic sp,#0xf'
>
> The problem is that the 'bic' instruction can't operate on the 'sp'
> register in Thumb2 mode. Fix it by using a temporary register. This
> isn't in the main loop, so the performance difference is negligible.
> This also matches what aes-neonbs-core.S does.
>
> Reported-by: Stefan Agner <[email protected]>
> Fixes: ede9622162fa ("crypto: arm/speck - add NEON-accelerated implementation of Speck-XTS")
> Signed-off-by: Eric Biggers <[email protected]>
> ---
> arch/arm/crypto/speck-neon-core.S | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/crypto/speck-neon-core.S b/arch/arm/crypto/speck-neon-core.S
> index 3c1e203e53b9..57caa742016e 100644
> --- a/arch/arm/crypto/speck-neon-core.S
> +++ b/arch/arm/crypto/speck-neon-core.S
> @@ -272,9 +272,11 @@
> * Allocate stack space to store 128 bytes worth of tweaks. For
> * performance, this space is aligned to a 16-byte boundary so that we
> * can use the load/store instructions that declare 16-byte alignment.
> + * For Thumb2 compatibility, don't do the 'bic' directly on 'sp'.
> */
> - sub sp, #128
> - bic sp, #0xf
> + sub r12, sp, #128
> + bic r12, #0xf
> + mov sp, r12
>
> .if \n == 64
> // Load first tweak
Acked-by: Ard Biesheuvel <[email protected]>
On 19.06.2018 00:33, Eric Biggers wrote:
> Building the kernel with CONFIG_THUMB2_KERNEL=y and
> CONFIG_CRYPTO_SPECK_NEON set fails with the following errors:
>
> arch/arm/crypto/speck-neon-core.S: Assembler messages:
>
> arch/arm/crypto/speck-neon-core.S:419: Error: r13 not allowed here
> -- `bic sp,#0xf'
> arch/arm/crypto/speck-neon-core.S:423: Error: r13 not allowed here
> -- `bic sp,#0xf'
> arch/arm/crypto/speck-neon-core.S:427: Error: r13 not allowed here
> -- `bic sp,#0xf'
> arch/arm/crypto/speck-neon-core.S:431: Error: r13 not allowed here
> -- `bic sp,#0xf'
>
> The problem is that the 'bic' instruction can't operate on the 'sp'
> register in Thumb2 mode. Fix it by using a temporary register. This
> isn't in the main loop, so the performance difference is negligible.
> This also matches what aes-neonbs-core.S does.
>
> Reported-by: Stefan Agner <[email protected]>
> Fixes: ede9622162fa ("crypto: arm/speck - add NEON-accelerated
> implementation of Speck-XTS")
> Signed-off-by: Eric Biggers <[email protected]>
> ---
> arch/arm/crypto/speck-neon-core.S | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/crypto/speck-neon-core.S
> b/arch/arm/crypto/speck-neon-core.S
> index 3c1e203e53b9..57caa742016e 100644
> --- a/arch/arm/crypto/speck-neon-core.S
> +++ b/arch/arm/crypto/speck-neon-core.S
> @@ -272,9 +272,11 @@
> * Allocate stack space to store 128 bytes worth of tweaks. For
> * performance, this space is aligned to a 16-byte boundary so that we
> * can use the load/store instructions that declare 16-byte alignment.
> + * For Thumb2 compatibility, don't do the 'bic' directly on 'sp'.
> */
> - sub sp, #128
> - bic sp, #0xf
> + sub r12, sp, #128
> + bic r12, #0xf
> + mov sp, r12
Looks good to me and compiles fine here. Thanks!
Reviewed-by: Stefan Agner <[email protected]>
--
Stefan
>
> .if \n == 64
> // Load first tweak
On Mon, Jun 18, 2018 at 03:33:23PM -0700, Eric Biggers wrote:
> Building the kernel with CONFIG_THUMB2_KERNEL=y and
> CONFIG_CRYPTO_SPECK_NEON set fails with the following errors:
>
> arch/arm/crypto/speck-neon-core.S: Assembler messages:
>
> arch/arm/crypto/speck-neon-core.S:419: Error: r13 not allowed here -- `bic sp,#0xf'
> arch/arm/crypto/speck-neon-core.S:423: Error: r13 not allowed here -- `bic sp,#0xf'
> arch/arm/crypto/speck-neon-core.S:427: Error: r13 not allowed here -- `bic sp,#0xf'
> arch/arm/crypto/speck-neon-core.S:431: Error: r13 not allowed here -- `bic sp,#0xf'
>
> The problem is that the 'bic' instruction can't operate on the 'sp'
> register in Thumb2 mode. Fix it by using a temporary register. This
> isn't in the main loop, so the performance difference is negligible.
> This also matches what aes-neonbs-core.S does.
>
> Reported-by: Stefan Agner <[email protected]>
> Fixes: ede9622162fa ("crypto: arm/speck - add NEON-accelerated implementation of Speck-XTS")
> Signed-off-by: Eric Biggers <[email protected]>
Patch applied. Thanks.
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt