From patchwork Thu Apr 2 05:40:13 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: AKASHI Takahiro X-Patchwork-Id: 6144341 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 78DEE9F1BE for ; Thu, 2 Apr 2015 05:45:23 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8E49120225 for ; Thu, 2 Apr 2015 05:45:22 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9A3DF2015A for ; Thu, 2 Apr 2015 05:45:21 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YdXtZ-0007u5-9G; Thu, 02 Apr 2015 05:42:25 +0000 Received: from mail-pa0-f42.google.com ([209.85.220.42]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1YdXsd-0007Fk-S6 for linux-arm-kernel@lists.infradead.org; Thu, 02 Apr 2015 05:41:29 +0000 Received: by pacgg7 with SMTP id gg7so74021073pac.0 for ; Wed, 01 Apr 2015 22:41:06 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=9BcsgzZgf0v8HMg8/RAfNwopoEXiWfS7NqvlKOjTHKQ=; b=CFpyP1fYpb74goPHHmyTuBS+z+6/J5X1a+Sb0UEI7B/wP/lRoAw+Qhum/MjVW7GwUU 2DV8nYwF93Bo+zJR4p+VpSZDpypPsQingX5BiFQ//4FALUkb/R1EM/L3wbgXqtX7j5sI bgQL80i4DUeG27Qu4GEgBOziHmVFMkhMkRpEreZPvdFunb32PU6Wql2/uEKbSGDvCwQz Sb2oxfR1qDlWVp2q0QMfvuHgPOM59j0M5Odb6ab9jRIv2wVp9opIoSKlNDTwMZKedQX1 Z8h3pe9jYeN0Wc2RkhYcO90kvAKZd7+gDpmBV1Kl+IvCW9IBsLTb1fPFnUpsbKG6htky edDQ== X-Gm-Message-State: ALoCoQmR2mz5RMub+isAztS3hIaofYXBDOgDFfBcRWZW4nb/AIDxhFYuCaf+wItnepy885RHy6mT X-Received: by 10.66.167.232 with SMTP id zr8mr83432272pab.23.1427953266461; Wed, 01 Apr 2015 22:41:06 -0700 (PDT) Received: from localhost.localdomain (61-205-5-51m5.grp1.mineo.jp. [61.205.5.51]) by mx.google.com with ESMTPSA id hb6sm3854757pbd.88.2015.04.01.22.41.00 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 01 Apr 2015 22:41:05 -0700 (PDT) From: AKASHI Takahiro To: catalin.marinas@arm.com, will.deacon@arm.com, marc.zyngier@arm.com, mark.rutland@arm.com Subject: [v3 2/5] arm64: kvm: allow EL2 context to be reset on shutdown Date: Thu, 2 Apr 2015 14:40:13 +0900 Message-Id: <1427953216-11737-3-git-send-email-takahiro.akashi@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1427953216-11737-1-git-send-email-takahiro.akashi@linaro.org> References: <1427953216-11737-1-git-send-email-takahiro.akashi@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150401_224127_980207_35FA1A81 X-CRM114-Status: GOOD ( 14.99 ) X-Spam-Score: -0.7 (/) Cc: linux-arm-kernel@lists.infradead.org, linaro-kernel@lists.linaro.org, geoff@infradead.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, AKASHI Takahiro , broonie@kernel.org, david.griego@linaro.org, christoffer.dall@linaro.org, freddy77@gmail.com X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The current kvm implementation keeps EL2 vector table installed even when the system is shut down. This prevents kexec from putting the system with kvm back into EL2 when starting a new kernel. This patch resolves this issue by calling a cpu tear-down function via reboot notifier, kvm_reboot_notify(), which is invoked by kernel_restart_prepare() in kernel_kexec(). While kvm has a generic hook, kvm_reboot(), we can't use it here because a cpu teardown function will not be invoked, under current implementation, if no guest vm has been created by kvm_create_vm(). Please note that kvm_usage_count is zero in this case. We'd better, in the future, implement cpu hotplug support and put the arch-specific initialization into kvm_arch_hardware_enable/disable(). This way, we would be able to revert this patch. Signed-off-by: AKASHI Takahiro --- arch/arm/kvm/arm.c | 21 +++++++++++++++++++++ arch/arm64/kvm/Kconfig | 1 - 2 files changed, 21 insertions(+), 1 deletion(-) diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 39df694..f64713e 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include #include @@ -1100,6 +1101,23 @@ struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) return NULL; } +static int kvm_reboot_notify(struct notifier_block *nb, + unsigned long val, void *v) +{ + /* + * Reset each CPU in EL2 to initial state. + */ + on_each_cpu(kvm_cpu_reset, NULL, 1); + + return NOTIFY_DONE; +} + +static struct notifier_block kvm_reboot_nb = { + .notifier_call = kvm_reboot_notify, + .next = NULL, + .priority = 0, /* FIXME */ +}; + /** * Initialize Hyp-mode and memory mappings on all CPUs. */ @@ -1138,6 +1156,9 @@ int kvm_arch_init(void *opaque) hyp_cpu_pm_init(); kvm_coproc_table_init(); + + register_reboot_notifier(&kvm_reboot_nb); + return 0; out_err: cpu_notifier_register_done(); diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index 30ae7a7..f5590c8 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -18,7 +18,6 @@ if VIRTUALIZATION config KVM bool "Kernel-based Virtual Machine (KVM) support" - depends on !KEXEC select MMU_NOTIFIER select PREEMPT_NOTIFIERS select ANON_INODES