From nobody Mon Feb 9 22:27:02 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1662709036563424.2287555391471; Fri, 9 Sep 2022 00:37:16 -0700 (PDT) Received: from localhost ([::1]:36592 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oWYZe-0003At-8x for importer@patchew.org; Fri, 09 Sep 2022 03:37:14 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:55740) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oWYWu-0002KA-7R for qemu-devel@nongnu.org; Fri, 09 Sep 2022 03:34:25 -0400 Received: from mail.loongson.cn ([114.242.206.163]:45700 helo=loongson.cn) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oWYWo-00060I-6E for qemu-devel@nongnu.org; Fri, 09 Sep 2022 03:34:24 -0400 Received: from localhost.localdomain (unknown [10.2.5.185]) by localhost.localdomain (Coremail) with SMTP id AQAAf8CxkOBr7Bpj4jQVAA--.20312S2; Fri, 09 Sep 2022 15:34:03 +0800 (CST) From: Song Gao To: qemu-devel@nongnu.org Cc: peter.maydell@linaro.org, richard.henderson@linaro.org, alex.bennee@linaro.org, maobibo@loongson.cn, gaosong@loongson.cn Subject: [RISU PATCH] risu: Use altermate stack Date: Fri, 9 Sep 2022 15:34:03 +0800 Message-Id: <20220909073403.159563-1-gaosong@loongson.cn> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: AQAAf8CxkOBr7Bpj4jQVAA--.20312S2 X-Coremail-Antispam: 1UD129KBjvJXoW7AryUWw4UtryUXw43uFyxAFb_yoW8JF43pw 43Ca4ftrZ8trW7X39xCrWkW39xJwn7A34UuF43Z3yUXayDGr9Yv3WDGFy3uFyxGFs8A3yD ZrZYka15uF4DCrJanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnUUvcSsGvfC2KfnxnUUI43ZEXa7xR_UUUUUUUUU== X-CM-SenderInfo: 5jdr20tqj6z05rqj20fqof0/ Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=114.242.206.163; envelope-from=gaosong@loongson.cn; helo=loongson.cn X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZM-MESSAGEID: 1662709038413100001 Content-Type: text/plain; charset="utf-8" We can use altermate stack, so that we can use sp register as intput/ouput = register. I had tested aarch64/LoongArch architecture. Signed-off-by: Song Gao --- risu.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/risu.c b/risu.c index 1c096a8..98dba94 100644 --- a/risu.c +++ b/risu.c @@ -329,7 +329,7 @@ static void set_sigill_handler(void (*fn) (int, siginfo= _t *, void *)) memset(&sa, 0, sizeof(struct sigaction)); =20 sa.sa_sigaction =3D fn; - sa.sa_flags =3D SA_SIGINFO; + sa.sa_flags =3D SA_SIGINFO | SA_ONSTACK; sigemptyset(&sa.sa_mask); if (sigaction(SIGILL, &sa, 0) !=3D 0) { perror("sigaction"); @@ -550,6 +550,7 @@ int main(int argc, char **argv) char *trace_fn =3D NULL; struct option *longopts; char *shortopts; + stack_t ss; =20 longopts =3D setup_options(&shortopts); =20 @@ -617,6 +618,19 @@ int main(int argc, char **argv) =20 load_image(imgfile); =20 + /* create altermate stack */ + ss.ss_sp =3D malloc(SIGSTKSZ); + if (ss.ss_sp =3D=3D NULL) { + perror("malloc"); + exit(EXIT_FAILURE); + } + ss.ss_size =3D SIGSTKSZ; + ss.ss_flags =3D 0; + if (sigaltstack(&ss, NULL) =3D=3D -1) { + perror("sigaltstac"); + exit(EXIT_FAILURE); + } + /* E.g. select requested SVE vector length. */ arch_init(); =20 --=20 2.31.1