From: Martin Schwidefsky Date: Fri, 4 Oct 2013 09:12:16 +0000 (+0200) Subject: s390/bpf,jit: fix prolog oddity X-Git-Tag: next-20131018~95^2~20 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=56388e90a20904a1e274162622687571d9956473;p=karo-tx-linux.git s390/bpf,jit: fix prolog oddity The prolog of functions generated by the bpf jit compiler uses an instruction sequence with an "ahi" instruction to create stack space instead of using an "aghi" instruction. Using the 32-bit "ahi" is not wrong as the stack we are operating on is an order-4 allocation which is always aligned to 16KB. But it is more consistent to use an "aghi" as the stack pointer is a 64-bit value. Signed-off-by: Martin Schwidefsky --- diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index b3444b44c4e6..b32188855997 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -156,8 +156,8 @@ static void bpf_jit_prologue(struct bpf_jit *jit) EMIT6(0xeb8ff058, 0x0024); /* lgr %r14,%r15 */ EMIT4(0xb90400ef); - /* ahi %r15, */ - EMIT4_IMM(0xa7fa0000, (jit->seen & SEEN_MEM) ? -112 : -80); + /* aghi %r15, */ + EMIT4_IMM(0xa7fb0000, (jit->seen & SEEN_MEM) ? -112 : -80); /* stg %r14,152(%r15) */ EMIT6(0xe3e0f098, 0x0024); } else if ((jit->seen & SEEN_XREG) && (jit->seen & SEEN_LITERAL))