From: Eric Biggers Subject: [PATCH] crypto: arm/speck - fix building in Thumb2 mode Date: Mon, 18 Jun 2018 15:33:23 -0700 Message-ID: <20180618223323.130072-1-ebiggers@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Eric Biggers , Stefan Agner , linux-arm-kernel@lists.infradead.org, Ard Biesheuvel To: linux-crypto@vger.kernel.org, Herbert Xu Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org List-Id: linux-crypto.vger.kernel.org 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 Fixes: ede9622162fa ("crypto: arm/speck - add NEON-accelerated implementation of Speck-XTS") Signed-off-by: Eric Biggers --- 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