From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37177) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gW53y-0003og-2l for qemu-devel@nongnu.org; Sun, 09 Dec 2018 14:48:29 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gW53u-0000Yw-3x for qemu-devel@nongnu.org; Sun, 09 Dec 2018 14:48:26 -0500 Received: from mail-wm1-x344.google.com ([2a00:1450:4864:20::344]:35524) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1gW53q-0008Q4-4F for qemu-devel@nongnu.org; Sun, 09 Dec 2018 14:48:18 -0500 Received: by mail-wm1-x344.google.com with SMTP id c126so9116051wmh.0 for ; Sun, 09 Dec 2018 11:48:10 -0800 (PST) Sender: =?UTF-8?Q?Philippe_Mathieu=2DDaud=C3=A9?= References: <20181207170951.7307-1-richard.henderson@linaro.org> From: =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= Message-ID: Date: Sun, 9 Dec 2018 20:48:07 +0100 MIME-Version: 1.0 In-Reply-To: <20181207170951.7307-1-richard.henderson@linaro.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] target/i386: Generate #UD when applying LOCK to a register List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Richard Henderson , qemu-devel@nongnu.org, Alberto Ortega Cc: pbonzini@redhat.com Cc'ing Alberto On 12/7/18 6:09 PM, Richard Henderson wrote: > This covers inc, dec, and the bit test instructions. > > I believe we've finally covered all of the cases for > which we have an atomic path that would use the cpu_A0 > temp, which is only initialized for address sources. > Reported-by: Alberto Ortega > Fixes: https://bugs.launchpad.net/qemu/+bug/1803160/comments/4 > Signed-off-by: Richard Henderson > --- > target/i386/translate.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/target/i386/translate.c b/target/i386/translate.c > index 0dd5fbe45c..eb52322a47 100644 > --- a/target/i386/translate.c > +++ b/target/i386/translate.c > @@ -1398,6 +1398,11 @@ static void gen_op(DisasContext *s1, int op, TCGMemOp ot, int d) > static void gen_inc(DisasContext *s1, TCGMemOp ot, int d, int c) > { > if (s1->prefix & PREFIX_LOCK) { > + if (d != OR_TMP0) { > + /* Lock prefix when destination is not memory. */ > + gen_illegal_opcode(s1); > + return; > + } > tcg_gen_movi_tl(s1->T0, c > 0 ? 1 : -1); > tcg_gen_atomic_add_fetch_tl(s1->T0, s1->A0, s1->T0, > s1->mem_index, ot | MO_LE); > @@ -6764,6 +6769,9 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu) > gen_op_ld_v(s, ot, s->T0, s->A0); > } > } else { > + if (s->prefix & PREFIX_LOCK) { > + goto illegal_op; > + } > gen_op_mov_v_reg(s, ot, s->T0, rm); > } > /* load shift */ > @@ -6803,6 +6811,9 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu) > gen_op_ld_v(s, ot, s->T0, s->A0); > } > } else { > + if (s->prefix & PREFIX_LOCK) { > + goto illegal_op; > + } > gen_op_mov_v_reg(s, ot, s->T0, rm); > } > bt_op: >