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author | Aurelien Jarno <aurelien@aurel32.net> | 2015-09-05 18:46:57 +0200 |
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committer | Ralf Baechle <ralf@linux-mips.org> | 2015-09-22 19:05:17 +0200 |
commit | b259e51f2e29390518021f9b8df55a3de42f371b (patch) | |
tree | 32f1e90749e9f2617805135817321f11b6bc640d | |
parent | MIPS: BPF: Avoid unreachable code on little endian (diff) | |
download | linux-b259e51f2e29390518021f9b8df55a3de42f371b.tar.xz linux-b259e51f2e29390518021f9b8df55a3de42f371b.zip |
MIPS: BPF: Fix build on pre-R2 little endian CPUs
The rotr, seh and wsbh instructions have been introduced with the R2
ISA. Thus the current BPF code fails to build on pre-R2 little endian
CPUs:
CC arch/mips/net/bpf_jit.o
AS arch/mips/net/bpf_jit_asm.o
/home/aurel32/linux-4.2/arch/mips/net/bpf_jit_asm.S: Assembler messages:
/home/aurel32/linux-4.2/arch/mips/net/bpf_jit_asm.S:67: Error: opcode not supported on this processor: mips32 (mips32) `wsbh $8,$19'
/home/aurel32/linux-4.2/arch/mips/net/bpf_jit_asm.S:68: Error: opcode not supported on this processor: mips32 (mips32) `rotr $19,$8,16'
/home/aurel32/linux-4.2/arch/mips/net/bpf_jit_asm.S:83: Error: opcode not supported on this processor: mips32 (mips32) `wsbh $8,$19'
/home/aurel32/linux-4.2/arch/mips/net/bpf_jit_asm.S:84: Error: opcode not supported on this processor: mips32 (mips32) `seh $19,$8'
/home/aurel32/linux-4.2/arch/mips/net/bpf_jit_asm.S:151: Error: opcode not supported on this processor: mips32 (mips32) `wsbh $8,$12'
/home/aurel32/linux-4.2/arch/mips/net/bpf_jit_asm.S:153: Error: opcode not supported on this processor: mips32 (mips32) `rotr $19,$8,16'
/home/aurel32/linux-4.2/arch/mips/net/bpf_jit_asm.S:164: Error: opcode not supported on this processor: mips32 (mips32) `wsbh $19,$12'
/home/aurel32/linux-4.2/scripts/Makefile.build:294: recipe for target 'arch/mips/net/bpf_jit_asm.o' failed
Fix that by providing equivalent code for these CPUs.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: stable@vger.kernel.org # v4.2+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11098/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
-rw-r--r-- | arch/mips/net/bpf_jit_asm.S | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/arch/mips/net/bpf_jit_asm.S b/arch/mips/net/bpf_jit_asm.S index 4f54cb18f104..dabf4179cd7e 100644 --- a/arch/mips/net/bpf_jit_asm.S +++ b/arch/mips/net/bpf_jit_asm.S @@ -64,8 +64,20 @@ sk_load_word_positive: PTR_ADDU t1, $r_skb_data, offset lw $r_A, 0(t1) #ifdef CONFIG_CPU_LITTLE_ENDIAN +# if defined(__mips_isa_rev) && (__mips_isa_rev >= 2) wsbh t0, $r_A rotr $r_A, t0, 16 +# else + sll t0, $r_A, 24 + srl t1, $r_A, 24 + srl t2, $r_A, 8 + or t0, t0, t1 + andi t2, t2, 0xff00 + andi t1, $r_A, 0xff00 + or t0, t0, t2 + sll t1, t1, 8 + or $r_A, t0, t1 +# endif #endif jr $r_ra move $r_ret, zero @@ -80,8 +92,16 @@ sk_load_half_positive: PTR_ADDU t1, $r_skb_data, offset lh $r_A, 0(t1) #ifdef CONFIG_CPU_LITTLE_ENDIAN +# if defined(__mips_isa_rev) && (__mips_isa_rev >= 2) wsbh t0, $r_A seh $r_A, t0 +# else + sll t0, $r_A, 24 + andi t1, $r_A, 0xff00 + sra t0, t0, 16 + srl t1, t1, 8 + or $r_A, t0, t1 +# endif #endif jr $r_ra move $r_ret, zero @@ -148,9 +168,22 @@ sk_load_byte_positive: NESTED(bpf_slow_path_word, (6 * SZREG), $r_sp) bpf_slow_path_common(4) #ifdef CONFIG_CPU_LITTLE_ENDIAN +# if defined(__mips_isa_rev) && (__mips_isa_rev >= 2) wsbh t0, $r_s0 jr $r_ra rotr $r_A, t0, 16 +# else + sll t0, $r_s0, 24 + srl t1, $r_s0, 24 + srl t2, $r_s0, 8 + or t0, t0, t1 + andi t2, t2, 0xff00 + andi t1, $r_s0, 0xff00 + or t0, t0, t2 + sll t1, t1, 8 + jr $r_ra + or $r_A, t0, t1 +# endif #else jr $r_ra move $r_A, $r_s0 @@ -161,8 +194,17 @@ NESTED(bpf_slow_path_word, (6 * SZREG), $r_sp) NESTED(bpf_slow_path_half, (6 * SZREG), $r_sp) bpf_slow_path_common(2) #ifdef CONFIG_CPU_LITTLE_ENDIAN +# if defined(__mips_isa_rev) && (__mips_isa_rev >= 2) jr $r_ra wsbh $r_A, $r_s0 +# else + sll t0, $r_s0, 8 + andi t1, $r_s0, 0xff00 + andi t0, t0, 0xff00 + srl t1, t1, 8 + jr $r_ra + or $r_A, t0, t1 +# endif #else jr $r_ra move $r_A, $r_s0 |