From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC4B6C004C9 for ; Tue, 7 May 2019 14:08:09 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C0394205ED for ; Tue, 7 May 2019 14:08:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C0394205ED Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([127.0.0.1]:47419 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hO0lM-0006rq-T0 for qemu-devel@archiver.kernel.org; Tue, 07 May 2019 10:08:08 -0400 Received: from eggs.gnu.org ([209.51.188.92]:42442) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hO0kL-0006Q6-3d for qemu-devel@nongnu.org; Tue, 07 May 2019 10:07:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hO0kH-0004SU-7o for qemu-devel@nongnu.org; Tue, 07 May 2019 10:07:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34338) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hO0kF-0004Ol-Ag for qemu-devel@nongnu.org; Tue, 07 May 2019 10:07:01 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A662B59449; Tue, 7 May 2019 14:06:56 +0000 (UTC) Received: from [10.40.204.24] (ovpn-204-24.brq.redhat.com [10.40.204.24]) by smtp.corp.redhat.com (Postfix) with ESMTP id AB971627D8; Tue, 7 May 2019 14:06:55 +0000 (UTC) To: Richard Henderson , qemu-devel@nongnu.org References: <20190506173353.32206-1-richard.henderson@linaro.org> <20190506173353.32206-13-richard.henderson@linaro.org> From: Laurent Vivier Message-ID: <6a5967a8-4835-7f6c-a50b-0154d88a2aed@redhat.com> Date: Tue, 7 May 2019 16:06:54 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20190506173353.32206-13-richard.henderson@linaro.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Tue, 07 May 2019 14:06:56 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH v4 12/24] linux-user: Initialize pseudo-random seeds for all guest cpus X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Laurent Vivier Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 06/05/2019 19:33, Richard Henderson wrote: > When the -seed option is given, call qemu_guest_random_seed_main, > putting the subsystem into deterministic mode. Pass derived seeds > to each cpu created during clone; which is a no-op unless the > subsystem is in deterministic mode. >=20 > Cc: Laurent Vivier > Reviewed-by: Philippe Mathieu-Daud=C3=A9 > Signed-off-by: Richard Henderson > --- > linux-user/main.c | 21 ++++++++++----------- > linux-user/syscall.c | 3 +++ > 2 files changed, 13 insertions(+), 11 deletions(-) >=20 > diff --git a/linux-user/main.c b/linux-user/main.c > index 3d2230320b..7dfb202e5d 100644 > --- a/linux-user/main.c > +++ b/linux-user/main.c > @@ -34,6 +34,7 @@ > #include "tcg.h" > #include "qemu/timer.h" > #include "qemu/envlist.h" > +#include "qemu/guest-random.h" > #include "elf.h" > #include "trace/control.h" > #include "target_elf.h" > @@ -48,6 +49,7 @@ static int gdbstub_port; > static envlist_t *envlist; > static const char *cpu_model; > static const char *cpu_type; > +static const char *seed_optarg; > unsigned long mmap_min_addr; > unsigned long guest_base; > int have_guest_base; > @@ -290,15 +292,9 @@ static void handle_arg_pagesize(const char *arg) > } > } > =20 > -static void handle_arg_randseed(const char *arg) > +static void handle_arg_seed(const char *arg) > { > - unsigned long long seed; > - > - if (parse_uint_full(arg, &seed, 0) !=3D 0 || seed > UINT_MAX) { > - fprintf(stderr, "Invalid seed number: %s\n", arg); > - exit(EXIT_FAILURE); > - } > - srand(seed); It's a detail, but I think you can't remove this srand() in this patch:=20 you initialize qemu_guest_random() sequence but the code continues to=20 use rand() to have a random number, so the seed value is in fact=20 ignored. you can remove it in PATCH 16. Thanks, Laurent