crypto: arm/aes-neonbs - avoid hacks to prevent Thumb2 mode switches

Instead of using a homegrown macrofied version of the adr instruction
that sets the Thumb bit in the output value, only to ensure that any
bx instructions consuming that value will not switch out of Thumb mode
when branching, use non-interworking mov (to PC) instructions, which
achieve the same thing.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/arch/arm/crypto/aes-neonbs-core.S b/arch/arm/crypto/aes-neonbs-core.S
index cfaed4e67535f5ef7453c76336b474cd1923868c..07cde1374bb042f610d9d95810aab8455c4e1fca 100644 (file)
--- a/arch/arm/crypto/aes-neonbs-core.S
+++ b/arch/arm/crypto/aes-neonbs-core.S
@@ -77,11 +77,6 @@
        vldr            \out\()h, \sym + 8
        .endm
 
-       .macro          __adr, reg, lbl
-       adr             \reg, \lbl
-THUMB( orr             \reg, \reg, #1          )
-       .endm
-
        .macro          in_bs_ch, b0, b1, b2, b3, b4, b5, b6, b7
        veor            \b2, \b2, \b1
        veor            \b5, \b5, \b6
@@ -629,11 +624,11 @@ ENDPROC(aesbs_decrypt8)
        push            {r4-r6, lr}
        ldr             r5, [sp, #16]           // number of blocks
 
-99:    __adr           ip, 0f
+99:    adr             ip, 0f
        and             lr, r5, #7
        cmp             r5, #8
        sub             ip, ip, lr, lsl #2
-       bxlt            ip                      // computed goto if blocks < 8
+       movlt           pc, ip                  // computed goto if blocks < 8
 
        vld1.8          {q0}, [r1]!
        vld1.8          {q1}, [r1]!
@@ -648,11 +643,11 @@ ENDPROC(aesbs_decrypt8)
        mov             rounds, r3
        bl              \do8
 
-       __adr           ip, 1f
+       adr             ip, 1f
        and             lr, r5, #7
        cmp             r5, #8
        sub             ip, ip, lr, lsl #2
-       bxlt            ip                      // computed goto if blocks < 8
+       movlt           pc, ip                  // computed goto if blocks < 8
 
        vst1.8          {\o0}, [r0]!
        vst1.8          {\o1}, [r0]!
@@ -689,12 +684,12 @@ ENTRY(aesbs_cbc_decrypt)
        push            {r4-r6, lr}
        ldm             ip, {r5-r6}             // load args 4-5
 
-99:    __adr           ip, 0f
+99:    adr             ip, 0f
        and             lr, r5, #7
        cmp             r5, #8
        sub             ip, ip, lr, lsl #2
        mov             lr, r1
-       bxlt            ip                      // computed goto if blocks < 8
+       movlt           pc, ip                  // computed goto if blocks < 8
 
        vld1.8          {q0}, [lr]!
        vld1.8          {q1}, [lr]!
@@ -718,11 +713,11 @@ ENTRY(aesbs_cbc_decrypt)
        vmov            q14, q8
        vmov            q15, q8
 
-       __adr           ip, 1f
+       adr             ip, 1f
        and             lr, r5, #7
        cmp             r5, #8
        sub             ip, ip, lr, lsl #2
-       bxlt            ip                      // computed goto if blocks < 8
+       movlt           pc, ip                  // computed goto if blocks < 8
 
        vld1.8          {q9}, [r1]!
        vld1.8          {q10}, [r1]!
@@ -733,9 +728,9 @@ ENTRY(aesbs_cbc_decrypt)
        vld1.8          {q15}, [r1]!
        W(nop)
 
-1:     __adr           ip, 2f
+1:     adr             ip, 2f
        sub             ip, ip, lr, lsl #3
-       bxlt            ip                      // computed goto if blocks < 8
+       movlt           pc, ip                  // computed goto if blocks < 8
 
        veor            q0, q0, q8
        vst1.8          {q0}, [r0]!
@@ -804,13 +799,13 @@ ENTRY(aesbs_ctr_encrypt)
        vmov            q6, q0
        vmov            q7, q0
 
-       __adr           ip, 0f
+       adr             ip, 0f
        sub             lr, r5, #1
        and             lr, lr, #7
        cmp             r5, #8
        sub             ip, ip, lr, lsl #5
        sub             ip, ip, lr, lsl #2
-       bxlt            ip                      // computed goto if blocks < 8
+       movlt           pc, ip                  // computed goto if blocks < 8
 
        next_ctr        q1
        next_ctr        q2
@@ -824,13 +819,13 @@ ENTRY(aesbs_ctr_encrypt)
        mov             rounds, r3
        bl              aesbs_encrypt8
 
-       __adr           ip, 1f
+       adr             ip, 1f
        and             lr, r5, #7
        cmp             r5, #8
        movgt           r4, #0
        ldrle           r4, [sp, #40]           // load final in the last round
        sub             ip, ip, lr, lsl #2
-       bxlt            ip                      // computed goto if blocks < 8
+       movlt           pc, ip                  // computed goto if blocks < 8
 
        vld1.8          {q8}, [r1]!
        vld1.8          {q9}, [r1]!
@@ -843,10 +838,10 @@ ENTRY(aesbs_ctr_encrypt)
 1:     bne             2f
        vld1.8          {q15}, [r1]!
 
-2:     __adr           ip, 3f
+2:     adr             ip, 3f
        cmp             r5, #8
        sub             ip, ip, lr, lsl #3
-       bxlt            ip                      // computed goto if blocks < 8
+       movlt           pc, ip                  // computed goto if blocks < 8
 
        veor            q0, q0, q8
        vst1.8          {q0}, [r0]!
@@ -900,12 +895,12 @@ __xts_prepare8:
        vshr.u64        d30, d31, #7
        vmov            q12, q14
 
-       __adr           ip, 0f
+       adr             ip, 0f
        and             r4, r6, #7
        cmp             r6, #8
        sub             ip, ip, r4, lsl #5
        mov             r4, sp
-       bxlt            ip                      // computed goto if blocks < 8
+       movlt           pc, ip                  // computed goto if blocks < 8
 
        vld1.8          {q0}, [r1]!
        next_tweak      q12, q14, q15, q13
@@ -973,12 +968,12 @@ ENDPROC(__xts_prepare8)
        mov             rounds, r3
        bl              \do8
 
-       __adr           ip, 0f
+       adr             ip, 0f
        and             lr, r6, #7
        cmp             r6, #8
        sub             ip, ip, lr, lsl #2
        mov             r4, sp
-       bxlt            ip                      // computed goto if blocks < 8
+       movlt           pc, ip                  // computed goto if blocks < 8
 
        vld1.8          {q8}, [r4, :128]!
        vld1.8          {q9}, [r4, :128]!
@@ -989,9 +984,9 @@ ENDPROC(__xts_prepare8)
        vld1.8          {q14}, [r4, :128]!
        vld1.8          {q15}, [r4, :128]
 
-0:     __adr           ip, 1f
+0:     adr             ip, 1f
        sub             ip, ip, lr, lsl #3
-       bxlt            ip                      // computed goto if blocks < 8
+       movlt           pc, ip                  // computed goto if blocks < 8
 
        veor            \o0, \o0, q8
        vst1.8          {\o0}, [r0]!