From patchwork Tue Sep 19 19:17:55 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Helge Deller X-Patchwork-Id: 13391788 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C8DA8CE79A9 for ; Tue, 19 Sep 2023 19:19:16 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qigEq-00064b-UE; Tue, 19 Sep 2023 15:18:24 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qigEm-000613-Hl; Tue, 19 Sep 2023 15:18:20 -0400 Received: from sin.source.kernel.org ([2604:1380:40e1:4800::1]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qigEk-0008A7-OU; Tue, 19 Sep 2023 15:18:20 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 0A87ECE1302; Tue, 19 Sep 2023 19:18:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C4E8EC433C9; Tue, 19 Sep 2023 19:18:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1695151093; bh=XmuE9aZ81k3K7jMFdg2gxPS8pizbwALL2hfdIcy4sdY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TeGT28BJSAeZ7+IFXjnwrLRflgG1ytedG5/QvsiDAg86unC3C+dHX0k8KYlJS0a8b M+t8ekUWSMeiBd1zNYRODUdxdxWTp2Hv+3DPtquK+SCrGJeaBG1n+gY165KbVYJfKJ +YZO9RCYyL+qV2jBpQEl57MC14+4yNKeO9SjcdpecFJPwrw07Ejlfti9GNqPBIyT05 KA1T9geYmvTRdTEAjhx5ZmspN4mUpEQngbTWBdK0kJbGw1GTPrfkSSgzodjTgsDi1+ OALyRZ2PMarNTzlPJ73TlOIl0HwRA/v4JMvedSKMrtHNu6TFlJHK2D3JF4tL8m2tmB XNK8etrpz+RQQ== From: deller@kernel.org To: qemu-devel@nongnu.org Cc: Helge Deller , Richard Henderson , Laurent Vivier , Mikulas Patocka , qemu-stable@nongnu.org Subject: [PULL v2 7/8] linux-user/hppa: clear the PSW 'N' bit when delivering signals Date: Tue, 19 Sep 2023 21:17:55 +0200 Message-ID: <20230919191757.98889-8-deller@kernel.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230919191757.98889-1-deller@kernel.org> References: <20230919191757.98889-1-deller@kernel.org> MIME-Version: 1.0 Received-SPF: pass client-ip=2604:1380:40e1:4800::1; envelope-from=deller@kernel.org; helo=sin.source.kernel.org X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Mikulas Patocka qemu-hppa may crash when delivering a signal. It can be demonstrated with this program. Compile the program with "hppa-linux-gnu-gcc -O2 signal.c" and run it with "qemu-hppa -one-insn-per-tb a.out". It reports that the address of the flag is 0xb4 and it crashes when attempting to touch it. #include #include #include #include sig_atomic_t flag; void sig(int n) { printf("&flag: %p\n", &flag); flag = 1; } int main(void) { struct sigaction sa; struct itimerval it; sa.sa_handler = sig; sigemptyset(&sa.sa_mask); sa.sa_flags = SA_RESTART; if (sigaction(SIGALRM, &sa, NULL)) perror("sigaction"), exit(1); it.it_interval.tv_sec = 0; it.it_interval.tv_usec = 100; it.it_value.tv_sec = it.it_interval.tv_sec; it.it_value.tv_usec = it.it_interval.tv_usec; if (setitimer(ITIMER_REAL, &it, NULL)) perror("setitimer"), exit(1); while (1) { } } The reason for the crash is that the signal handling routine doesn't clear the 'N' flag in the PSW. If the signal interrupts a thread when the 'N' flag is set, the flag remains set at the beginning of the signal handler and the first instruction of the signal handler is skipped. Signed-off-by: Mikulas Patocka Acked-by: Helge Deller Cc: qemu-stable@nongnu.org Signed-off-by: Helge Deller --- linux-user/hppa/signal.c | 1 + 1 file changed, 1 insertion(+) diff --git a/linux-user/hppa/signal.c b/linux-user/hppa/signal.c index f253a15864..3a976ac693 100644 --- a/linux-user/hppa/signal.c +++ b/linux-user/hppa/signal.c @@ -159,6 +159,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, } env->iaoq_f = haddr; env->iaoq_b = haddr + 4; + env->psw_n = 0; return; give_sigsegv: