From patchwork Fri May 27 14:51:55 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Maydell X-Patchwork-Id: 9138609 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id C5D526075A for ; Fri, 27 May 2016 14:56:19 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B87E627B90 for ; Fri, 27 May 2016 14:56:19 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AD63F28096; Fri, 27 May 2016 14:56:19 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 659FE27B90 for ; Fri, 27 May 2016 14:56:19 +0000 (UTC) Received: from localhost ([::1]:46453 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b6JBS-0003ko-ER for patchwork-qemu-devel@patchwork.kernel.org; Fri, 27 May 2016 10:56:18 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49547) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b6J9W-0002PN-Vr for qemu-devel@nongnu.org; Fri, 27 May 2016 10:54:19 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1b6J9V-0005nM-1M for qemu-devel@nongnu.org; Fri, 27 May 2016 10:54:17 -0400 Received: from orth.archaic.org.uk ([2001:8b0:1d0::2]:57388) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b6J9U-0005mS-Qc for qemu-devel@nongnu.org; Fri, 27 May 2016 10:54:16 -0400 Received: from pm215 by orth.archaic.org.uk with local (Exim 4.84_2) (envelope-from ) id 1b6J7Q-0004lN-G6; Fri, 27 May 2016 15:52:08 +0100 From: Peter Maydell To: qemu-devel@nongnu.org Date: Fri, 27 May 2016 15:51:55 +0100 Message-Id: <1464360721-14359-14-git-send-email-peter.maydell@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1464360721-14359-1-git-send-email-peter.maydell@linaro.org> References: <1464360721-14359-1-git-send-email-peter.maydell@linaro.org> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2001:8b0:1d0::2 Subject: [Qemu-devel] [PATCH v2 13/19] linux-user: pause() should not pause if signal pending 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: Riku Voipio , Timothy Edward Baldwin , patches@linaro.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Timothy E Baldwin Fix races between signal handling and the pause syscall by reimplementing it using block_signals() and sigsuspend(). (Using safe_syscall(pause) would also work, except that the pause syscall doesn't exist on all architectures.) Signed-off-by: Timothy Edward Baldwin Message-id: 1441497448-32489-28-git-send-email-T.E.Baldwin99@members.leeds.ac.uk [PMM: tweaked commit message] Reviewed-by: Peter Maydell Signed-off-by: Peter Maydell --- linux-user/syscall.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 5a34642..3fc9c8a 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -6418,7 +6418,10 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1, #endif #ifdef TARGET_NR_pause /* not on alpha */ case TARGET_NR_pause: - ret = get_errno(pause()); + if (!block_signals()) { + sigsuspend(&((TaskState *)cpu->opaque)->signal_mask); + } + ret = -TARGET_EINTR; break; #endif #ifdef TARGET_NR_utime