s390/bpf: Fix ALU_NEG (A = -A)
Currently the LOAD NEGATIVE (lnr) instruction is used for ALU_NEG. This
instruction always loads the negative value. Therefore, if A is already
negative, it remains unchanged. To fix this use LOAD COMPLEMENT (lcr)
instead.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index c52ac77..8bc474f 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -431,8 +431,8 @@
EMIT4_DISP(0x88500000, K);
break;
case BPF_ALU | BPF_NEG: /* A = -A */
- /* lnr %r5,%r5 */
- EMIT2(0x1155);
+ /* lcr %r5,%r5 */
+ EMIT2(0x1355);
break;
case BPF_JMP | BPF_JA: /* ip += K */
offset = addrs[i + K] + jit->start - jit->prg;