From patchwork Fri Jan 27 18:11:33 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Claudio Imbrenda X-Patchwork-Id: 9542467 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 7B82E601D7 for ; Fri, 27 Jan 2017 18:12:16 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6DDE827F54 for ; Fri, 27 Jan 2017 18:12:16 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 626F627FBB; Fri, 27 Jan 2017 18:12:16 +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 C54BA27F54 for ; Fri, 27 Jan 2017 18:12:15 +0000 (UTC) Received: from localhost ([::1]:47226 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cXB0Q-0001p0-R8 for patchwork-qemu-devel@patchwork.kernel.org; Fri, 27 Jan 2017 13:12:14 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39623) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cXB02-0001mb-BB for qemu-devel@nongnu.org; Fri, 27 Jan 2017 13:11:51 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cXAzx-0008Ib-NS for qemu-devel@nongnu.org; Fri, 27 Jan 2017 13:11:50 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:49219) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cXAzx-0008Hv-Dd for qemu-devel@nongnu.org; Fri, 27 Jan 2017 13:11:45 -0500 Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v0RI93Rd043621 for ; Fri, 27 Jan 2017 13:11:41 -0500 Received: from e06smtp08.uk.ibm.com (e06smtp08.uk.ibm.com [195.75.94.104]) by mx0a-001b2d01.pphosted.com with ESMTP id 2884kb04s2-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Fri, 27 Jan 2017 13:11:41 -0500 Received: from localhost by e06smtp08.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Fri, 27 Jan 2017 18:11:37 -0000 Received: from b06cxnps4075.portsmouth.uk.ibm.com (d06relay12.portsmouth.uk.ibm.com [9.149.109.197]) by d06dlp01.portsmouth.uk.ibm.com (Postfix) with ESMTP id 22A4E17D8056; Fri, 27 Jan 2017 18:14:35 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v0RIBa048847616; Fri, 27 Jan 2017 18:11:36 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 437674C04E; Fri, 27 Jan 2017 18:11:33 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 100DF4C040; Fri, 27 Jan 2017 18:11:33 +0000 (GMT) Received: from p-imbrenda.boeblingen.de.ibm.com (unknown [9.152.224.26]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Fri, 27 Jan 2017 18:11:33 +0000 (GMT) From: Claudio Imbrenda To: pbonzini@redhat.com Date: Fri, 27 Jan 2017 19:11:33 +0100 X-Mailer: git-send-email 1.9.1 In-Reply-To: <1485540693-31723-1-git-send-email-imbrenda@linux.vnet.ibm.com> References: <1485540693-31723-1-git-send-email-imbrenda@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 17012718-0032-0000-0000-000007127CAF X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17012718-0033-0000-0000-0000233AE1D7 Message-Id: <1485540693-31723-3-git-send-email-imbrenda@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-01-27_13:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=3 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1612050000 definitions=main-1701270177 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.156.1 Subject: [Qemu-devel] [PATCH v7 2/2] gdbstub: Fix vCont behaviour 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: borntraeger@de.ibm.com, alex.bennee@linaro.org, qemu-devel@nongnu.org, palves@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP When GDB issues a "vCont", QEMU was not handling it correctly when multiple VCPUs are active. For vCont, for each thread (VCPU), it can be specified whether to single step, continue or stop that thread. The default is to stop a thread. However, when (for example) "vCont;s:2" is issued, all VCPUs continue to run, although all but VCPU nr 2 are to be stopped. This patch completely rewrites the vCont parsing code. Please note that this improvement only works in system emulation mode, when in userspace emulation mode the old behaviour is preserved. Signed-off-by: Claudio Imbrenda --- gdbstub.c | 194 +++++++++++++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 147 insertions(+), 47 deletions(-) diff --git a/gdbstub.c b/gdbstub.c index de9b62b..c298bf0 100644 --- a/gdbstub.c +++ b/gdbstub.c @@ -386,6 +386,51 @@ static inline void gdb_continue(GDBState *s) #endif } +/* + * Resume execution, per CPU actions. For user-mode emulation it's + * equivalent to gdb_continue. + */ +static int gdb_continue_partial(GDBState *s, char *newstates) +{ + int res = 0; +#ifdef CONFIG_USER_ONLY + s->running_state = 1; +#else + CPUState *cpu; + int flag = 0; + + if (!runstate_needs_reset()) { + if (vm_prepare_start()) { + return 0; + } + + CPU_FOREACH(cpu) { + switch (newstates[cpu_index(cpu) - 1]) { + case 0: + case 1: + break; /* nothing to do here */ + case 's': + cpu_single_step(cpu, sstep_flags); + cpu_resume(cpu); + flag = 1; + break; + case 'c': + cpu_resume(cpu); + flag = 1; + break; + default: + res = -1; + break; + } + } + } + if (flag) { + qemu_clock_enable(QEMU_CLOCK_VIRTUAL, true); + } +#endif + return res; +} + static void put_buffer(GDBState *s, const uint8_t *buf, int len) { #ifdef CONFIG_USER_ONLY @@ -784,6 +829,101 @@ static int is_query_packet(const char *p, const char *query, char separator) (p[query_len] == '\0' || p[query_len] == separator); } +/** + * gdb_handle_vcont - Parses and handles a vCont packet. + * returns -ENOTSUP if a command is unsupported, -EINVAL or -ERANGE if there is + * a format error, 0 on success. + */ +static int gdb_handle_vcont(GDBState *s, const char *p) +{ + int res, idx, signal = 0; + char cur_action; + char *newstates; + unsigned long tmp; + CPUState *cpu; +#ifdef CONFIG_USER_ONLY + int max_cpus = 1; /* global variable max_cpus exists only in system mode */ + + CPU_FOREACH(cpu) { + max_cpus = max_cpus < cpu_index(cpu) ? cpu_index(cpu) : max_cpus; + } +#endif + /* uninitialised CPUs stay 0 */ + newstates = g_new0(char, max_cpus); + + /* mark valid CPUs with 1 */ + CPU_FOREACH(cpu) { + newstates[cpu_index(cpu) - 1] = 1; + } + + /* + * res keeps track of what error we are returning, with -1 meaning + * that the command is unknown or unsupported, and thus returning + * an empty packet, while -22 returns an E22 packet due to + * invalid or incorrect parameters passed. + */ + res = 0; + while (*p) { + if (*p++ != ';') { + res = -ENOTSUP; + goto out; + } + + cur_action = *p++; + if (cur_action == 'C' || cur_action == 'S') { + cur_action = tolower(cur_action); + res = qemu_strtoul(p + 1, &p, 16, &tmp); + if (res) { + goto out; + } + signal = gdb_signal_to_target(tmp); + } else if (cur_action != 'c' && cur_action != 's') { + /* unknown/invalid/unsupported command */ + res = -ENOTSUP; + goto out; + } + /* thread specification. special values: (none), -1 = all; 0 = any */ + if ((p[0] == ':' && p[1] == '-' && p[2] == '1') || (p[0] != ':')) { + if (*p == ':') { + p += 3; + } + for (idx = 0; idx < max_cpus; idx++) { + if (newstates[idx] == 1) { + newstates[idx] = cur_action; + } + } + } else if (*p == ':') { + p++; + res = qemu_strtoul(p, &p, 16, &tmp); + if (res) { + goto out; + } + idx = tmp; + /* 0 means any thread, so we pick the first valid CPU */ + if (!idx) { + idx = cpu_index(first_cpu); + } + + /* invalid CPU specified */ + if (!idx || idx > max_cpus || !newstates[idx - 1]) { + res = -EINVAL; + goto out; + } + /* only use if no previous match occourred */ + if (newstates[idx - 1] == 1) { + newstates[idx - 1] = cur_action; + } + } + } + s->signal = signal; + gdb_continue_partial(s, newstates); + +out: + g_free(newstates); + + return res; +} + static int gdb_handle_packet(GDBState *s, const char *line_buf) { CPUState *cpu; @@ -829,60 +969,20 @@ static int gdb_handle_packet(GDBState *s, const char *line_buf) return RS_IDLE; case 'v': if (strncmp(p, "Cont", 4) == 0) { - int res_signal, res_thread; - p += 4; if (*p == '?') { put_packet(s, "vCont;c;C;s;S"); break; } - res = 0; - res_signal = 0; - res_thread = 0; - while (*p) { - int action, signal; - - if (*p++ != ';') { - res = 0; - break; - } - action = *p++; - signal = 0; - if (action == 'C' || action == 'S') { - signal = gdb_signal_to_target(strtoul(p, (char **)&p, 16)); - if (signal == -1) { - signal = 0; - } - } else if (action != 'c' && action != 's') { - res = 0; - break; - } - thread = 0; - if (*p == ':') { - thread = strtoull(p+1, (char **)&p, 16); - } - action = tolower(action); - if (res == 0 || (res == 'c' && action == 's')) { - res = action; - res_signal = signal; - res_thread = thread; - } - } + + res = gdb_handle_vcont(s, p); + if (res) { - if (res_thread != -1 && res_thread != 0) { - cpu = find_cpu(res_thread); - if (cpu == NULL) { - put_packet(s, "E22"); - break; - } - s->c_cpu = cpu; - } - if (res == 's') { - cpu_single_step(s->c_cpu, sstep_flags); + if ((res == -EINVAL) || (res == -ERANGE)) { + put_packet(s, "E22"); + break; } - s->signal = res_signal; - gdb_continue(s); - return RS_IDLE; + goto unknown_command; } break; } else {