From patchwork Tue Mar 12 08:52:29 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gibson X-Patchwork-Id: 10849023 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 314C91669 for ; Tue, 12 Mar 2019 10:14:07 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1FBEB28E8B for ; Tue, 12 Mar 2019 10:14:07 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1338828F23; Tue, 12 Mar 2019 10:14:07 +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=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI autolearn=ham version=3.3.1 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.wl.linuxfoundation.org (Postfix) with ESMTPS id 9062128E8B for ; Tue, 12 Mar 2019 10:14:06 +0000 (UTC) Received: from localhost ([127.0.0.1]:48873 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1h3eQ9-0003WS-SJ for patchwork-qemu-devel@patchwork.kernel.org; Tue, 12 Mar 2019 06:14:05 -0400 Received: from eggs.gnu.org ([209.51.188.92]:52411) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1h3dUG-0007ay-UI for qemu-devel@nongnu.org; Tue, 12 Mar 2019 05:14:18 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1h3dFf-00049V-2C for qemu-devel@nongnu.org; Tue, 12 Mar 2019 04:59:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59358) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1h3dFe-00047h-Ql; Tue, 12 Mar 2019 04:59:11 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 74A4E8552E; Tue, 12 Mar 2019 08:54:09 +0000 (UTC) Received: from umbus.redhat.com (vpn2-54-33.bne.redhat.com [10.64.54.33]) by smtp.corp.redhat.com (Postfix) with ESMTP id 22D376013E; Tue, 12 Mar 2019 08:54:06 +0000 (UTC) From: David Gibson To: peter.maydell@linaro.org Date: Tue, 12 Mar 2019 19:52:29 +1100 Message-Id: <20190312085316.8054-16-dgibson@redhat.com> In-Reply-To: <20190312085316.8054-1-dgibson@redhat.com> References: <20190312085316.8054-1-dgibson@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Tue, 12 Mar 2019 08:54:09 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 15/62] target/ppc: Refactor kvm_handle_debug 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: lvivier@redhat.com, clg@kaod.org, qemu-ppc@nongnu.org, qemu-devel@nongnu.org, groug@kaod.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Fabiano Rosas There are four scenarios being handled in this function: - single stepping - hardware breakpoints - software breakpoints - fallback (no debug supported) A future patch will add code to handle specific single step and software breakpoints cases so let's split each scenario into its own function now to avoid hurting readability. Signed-off-by: Fabiano Rosas Reviewed-by: Alexey Kardashevskiy Message-Id: <20190228225759.21328-5-farosas@linux.ibm.com> Signed-off-by: David Gibson --- target/ppc/kvm.c | 86 ++++++++++++++++++++++++++++-------------------- 1 file changed, 50 insertions(+), 36 deletions(-) diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c index a54fb9f0a8..4a79a75f63 100644 --- a/target/ppc/kvm.c +++ b/target/ppc/kvm.c @@ -1624,52 +1624,66 @@ static int kvm_handle_hw_breakpoint(CPUState *cs, return handle; } +static int kvm_handle_singlestep(void) +{ + return 1; +} + +static int kvm_handle_sw_breakpoint(void) +{ + return 1; +} + static int kvm_handle_debug(PowerPCCPU *cpu, struct kvm_run *run) { CPUState *cs = CPU(cpu); CPUPPCState *env = &cpu->env; struct kvm_debug_exit_arch *arch_info = &run->debug.arch; - int handle = 0; if (cs->singlestep_enabled) { - handle = 1; - } else if (arch_info->status) { - handle = kvm_handle_hw_breakpoint(cs, arch_info); - } else if (kvm_find_sw_breakpoint(cs, arch_info->address)) { - handle = 1; - } else { - /* QEMU is not able to handle debug exception, so inject - * program exception to guest; - * Yes program exception NOT debug exception !! - * When QEMU is using debug resources then debug exception must - * be always set. To achieve this we set MSR_DE and also set - * MSRP_DEP so guest cannot change MSR_DE. - * When emulating debug resource for guest we want guest - * to control MSR_DE (enable/disable debug interrupt on need). - * Supporting both configurations are NOT possible. - * So the result is that we cannot share debug resources - * between QEMU and Guest on BOOKE architecture. - * In the current design QEMU gets the priority over guest, - * this means that if QEMU is using debug resources then guest - * cannot use them; - * For software breakpoint QEMU uses a privileged instruction; - * So there cannot be any reason that we are here for guest - * set debug exception, only possibility is guest executed a - * privileged / illegal instruction and that's why we are - * injecting a program interrupt. - */ + return kvm_handle_singlestep(); + } - cpu_synchronize_state(cs); - /* env->nip is PC, so increment this by 4 to use - * ppc_cpu_do_interrupt(), which set srr0 = env->nip - 4. - */ - env->nip += 4; - cs->exception_index = POWERPC_EXCP_PROGRAM; - env->error_code = POWERPC_EXCP_INVAL; - ppc_cpu_do_interrupt(cs); + if (arch_info->status) { + return kvm_handle_hw_breakpoint(cs, arch_info); } - return handle; + if (kvm_find_sw_breakpoint(cs, arch_info->address)) { + return kvm_handle_sw_breakpoint(); + } + + /* + * QEMU is not able to handle debug exception, so inject + * program exception to guest; + * Yes program exception NOT debug exception !! + * When QEMU is using debug resources then debug exception must + * be always set. To achieve this we set MSR_DE and also set + * MSRP_DEP so guest cannot change MSR_DE. + * When emulating debug resource for guest we want guest + * to control MSR_DE (enable/disable debug interrupt on need). + * Supporting both configurations are NOT possible. + * So the result is that we cannot share debug resources + * between QEMU and Guest on BOOKE architecture. + * In the current design QEMU gets the priority over guest, + * this means that if QEMU is using debug resources then guest + * cannot use them; + * For software breakpoint QEMU uses a privileged instruction; + * So there cannot be any reason that we are here for guest + * set debug exception, only possibility is guest executed a + * privileged / illegal instruction and that's why we are + * injecting a program interrupt. + */ + cpu_synchronize_state(cs); + /* + * env->nip is PC, so increment this by 4 to use + * ppc_cpu_do_interrupt(), which set srr0 = env->nip - 4. + */ + env->nip += 4; + cs->exception_index = POWERPC_EXCP_PROGRAM; + env->error_code = POWERPC_EXCP_INVAL; + ppc_cpu_do_interrupt(cs); + + return 0; } int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run)