4.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Biggers <ebiggers@xxxxxxxxxx> [ Upstream commit a068b94d74ddb7776ca707b6d39d1ac0d2d057e6 ] 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 <stefan@xxxxxxxx> Fixes: ede9622162fa ("crypto: arm/speck - add NEON-accelerated implementation of Speck-XTS") Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> Acked-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> Reviewed-by: Stefan Agner <stefan@xxxxxxxx> Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm/crypto/speck-neon-core.S | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- 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