From patchwork Fri Jan 6 01:32:44 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: James Hogan X-Patchwork-Id: 9499835 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 3C3BA606DE for ; Fri, 6 Jan 2017 01:33:58 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2FE2328477 for ; Fri, 6 Jan 2017 01:33:58 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 24D3F2848B; Fri, 6 Jan 2017 01:33:58 +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 vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C1C3428477 for ; Fri, 6 Jan 2017 01:33:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752185AbdAFBdz (ORCPT ); Thu, 5 Jan 2017 20:33:55 -0500 Received: from mailapp01.imgtec.com ([195.59.15.196]:42955 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752111AbdAFBdk (ORCPT ); Thu, 5 Jan 2017 20:33:40 -0500 Received: from HHMAIL01.hh.imgtec.org (unknown [10.100.10.19]) by Forcepoint Email with ESMTPS id 1EEECE3D3EE8; Fri, 6 Jan 2017 01:33:37 +0000 (GMT) Received: from jhogan-linux.le.imgtec.org (192.168.154.110) by HHMAIL01.hh.imgtec.org (10.100.10.21) with Microsoft SMTP Server (TLS) id 14.3.294.0; Fri, 6 Jan 2017 01:33:37 +0000 From: James Hogan To: CC: James Hogan , Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Ralf Baechle , Subject: [PATCH 12/30] KVM: MIPS/T&E: active_mm = init_mm in guest context Date: Fri, 6 Jan 2017 01:32:44 +0000 Message-ID: <2cb054b4510d0cd88605f1ec258843f86b83000b.1483665879.git-series.james.hogan@imgtec.com> X-Mailer: git-send-email 2.11.0 MIME-Version: 1.0 In-Reply-To: References: X-Originating-IP: [192.168.154.110] Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Set init_mm as the active_mm and update mm_cpumask(current->mm) to reflect that it isn't active when in guest context. This prevents cache management code from attempting cache flushes on host virtual addresses while in guest context, for example due to a cache management IPIs or later when writing of dynamically translated code hits copy on write. Signed-off-by: James Hogan Cc: Paolo Bonzini Cc: "Radim Krčmář" Cc: Ralf Baechle Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org --- arch/mips/kvm/trap_emul.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/mips/kvm/trap_emul.c b/arch/mips/kvm/trap_emul.c index 3e1dbcbcea85..ab3750f6a768 100644 --- a/arch/mips/kvm/trap_emul.c +++ b/arch/mips/kvm/trap_emul.c @@ -670,6 +670,8 @@ static int kvm_trap_emul_vcpu_load(struct kvm_vcpu *vcpu, int cpu) write_c0_entryhi(cpu_asid(cpu, kern_mm)); else write_c0_entryhi(cpu_asid(cpu, user_mm)); + cpumask_clear_cpu(cpu, mm_cpumask(current->active_mm)); + current->active_mm = &init_mm; ehb(); } @@ -689,6 +691,8 @@ static int kvm_trap_emul_vcpu_put(struct kvm_vcpu *vcpu, int cpu) get_new_mmu_context(current->mm, cpu); } write_c0_entryhi(cpu_asid(cpu, current->mm)); + cpumask_set_cpu(cpu, mm_cpumask(current->mm)); + current->active_mm = current->mm; ehb(); } @@ -723,7 +727,7 @@ static void kvm_trap_emul_vcpu_reenter(struct kvm_run *run, static int kvm_trap_emul_vcpu_run(struct kvm_run *run, struct kvm_vcpu *vcpu) { - int cpu; + int cpu = smp_processor_id(); int r; /* Check if we have any exceptions/interrupts pending */ @@ -735,6 +739,14 @@ static int kvm_trap_emul_vcpu_run(struct kvm_run *run, struct kvm_vcpu *vcpu) /* Disable hardware page table walking while in guest */ htw_stop(); + /* + * While in guest context we're in the guest's address space, not the + * host process address space, so we need to be careful not to confuse + * e.g. cache management IPIs. + */ + cpumask_clear_cpu(cpu, mm_cpumask(current->active_mm)); + current->active_mm = &init_mm; + r = vcpu->arch.vcpu_run(run, vcpu); /* We may have migrated while handling guest exits */ @@ -745,6 +757,8 @@ static int kvm_trap_emul_vcpu_run(struct kvm_run *run, struct kvm_vcpu *vcpu) asid_version_mask(cpu))) get_new_mmu_context(current->mm, cpu); write_c0_entryhi(cpu_asid(cpu, current->mm)); + cpumask_set_cpu(cpu, mm_cpumask(current->mm)); + current->active_mm = current->mm; htw_start();