From patchwork Sun Mar 10 08:26:18 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gibson X-Patchwork-Id: 10846153 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 CEDBE1575 for ; Sun, 10 Mar 2019 08:41:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B713128F82 for ; Sun, 10 Mar 2019 08:41:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A732D28F84; Sun, 10 Mar 2019 08:41:54 +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=-2.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 9A4DD28F82 for ; Sun, 10 Mar 2019 08:41:53 +0000 (UTC) Received: from localhost ([127.0.0.1]:41914 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1h2u1o-0004mu-Kb for patchwork-qemu-devel@patchwork.kernel.org; Sun, 10 Mar 2019 04:41:52 -0400 Received: from eggs.gnu.org ([209.51.188.92]:42734) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1h2to4-0000sJ-Ag for qemu-devel@nongnu.org; Sun, 10 Mar 2019 04:27:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1h2to2-0001Hv-TP for qemu-devel@nongnu.org; Sun, 10 Mar 2019 04:27:40 -0400 Received: from ozlabs.org ([2401:3900:2:1::2]:50977) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1h2to2-00019M-1x; Sun, 10 Mar 2019 04:27:38 -0400 Received: by ozlabs.org (Postfix, from userid 1007) id 44HDqm2jSRz9sNd; Sun, 10 Mar 2019 19:27:15 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gibson.dropbear.id.au; s=201602; t=1552206436; bh=EPFCFM0Wz3Smeb5tbcd/vlOcxxIXdN7YVkJgNHCsTME=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WXCtI69Xf4mAdJXVLK6QN3KGMcEGI25i7EYj9WF27z1JSi6wFu3ha4BTm9HTnFDh/ 6T7D3FfW+Jsn7A7xw2jxeZR0xLbRaGsOXGlk6zDQCmk814HV9KhKTnesBTDmDkJPsS LMeDSqgrkL01uqn4rxF+KcZk33uEmedIshWVezuU= From: David Gibson To: peter.maydell@linaro.org Date: Sun, 10 Mar 2019 19:26:18 +1100 Message-Id: <20190310082703.1245-16-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190310082703.1245-1-david@gibson.dropbear.id.au> References: <20190310082703.1245-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2401:3900:2:1::2 Subject: [Qemu-devel] [PULL 15/60] 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, Fabiano Rosas , Alexey Kardashevskiy , groug@kaod.org, qemu-devel@nongnu.org, qemu-ppc@nongnu.org, David Gibson 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 996b08a1d3..4e3f1e4b78 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)