From patchwork Tue Jun 7 16:50:46 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kalesh Singh X-Patchwork-Id: 12872146 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C79B1C43334 for ; Tue, 7 Jun 2022 16:57:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:From:Subject:References: Mime-Version:Message-Id:In-Reply-To:Date:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=wOpOOXXceBXQWPPNbiFPuXKzxm733B2qEMjCYFQkIW0=; b=IWLVjoIw7Vl/kBjnbnkewajQDY Lo77N5nMblvn9SfsjWZOHy+AjmetandLe49QPeqENXFWatqOC9AMaeIaH5u/Ycdq4hKViqOAWsONX PVIA83eH0IkDTUnlPw0DVOkJv+ff3SdKAfFv05Z8CX/8vEoPkFG4m5hs3TYW9H2RBSHfGODZVToQ5 sBb9/RIL/ClMXA+K7ZwT8Jla7yoOyxxeXTi+4QbY9A6z60/MGKl9cQjRcpHSTKsGRA6xlUsuxl1Qa DGt5oDL1MiJ5tgCt+3BCIS6bULA+YXjoovHTKyPP0RtQ7jofr6XB8olse1STNmYiFst6Syn26tU9v HHTMC4VA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nycUv-008VMI-Sr; Tue, 07 Jun 2022 16:56:06 +0000 Received: from mail-pj1-x1049.google.com ([2607:f8b0:4864:20::1049]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nycUs-008VLD-Uv for linux-arm-kernel@lists.infradead.org; Tue, 07 Jun 2022 16:56:04 +0000 Received: by mail-pj1-x1049.google.com with SMTP id hf12-20020a17090aff8c00b001e2c0a2584cso7100969pjb.1 for ; Tue, 07 Jun 2022 09:56:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=0VHqSpYj40pidwvqadPpnWxx4OZYKsR2ZljfrIJfKyE=; b=BeaU0wAa2g0Kiu5D1gmb5uJ76d5AlU9rIdKN+WKMfPZXCRaPDOZBeHGCb2YXAwixzI OCBny7z0nInd3F0lowOxrNMPOTwmqhRt9oX2f6UGqzs8Oen4JP8iVFII0AS/WKCB7LqD jIsycA3VZfWRs5Fm2yn5GtlJfWCb8qQJGPwObJYjk4GDn3r8aa9TSi+529JuJeETKo3/ 84fYQv31ibh/BGHYCOmG57ssI0vQEjktcHUHxnCJUxTUih+7EdUXIXmgq3d33ilfDCbA JFh/tPiGwAvstxtB5QdVm4cVf74EAJvixcorLVxLr1Bor3M/N6AqphbawD+oB21uPfm/ PlMw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=0VHqSpYj40pidwvqadPpnWxx4OZYKsR2ZljfrIJfKyE=; b=mPrpHANgdPYc5ZntMbcfgiZ2OmddDuVsjPCzYh/qJLNDqGsDZaaEKXw6670sgGxAVC QCa0PrDJw27v/1pOV2RQykp7fSzuQjHvRL60CDlaOjS+jX5JkrmB+OuhgP7noSrvmJJl bzGytqq8QR4p8mUj5UKUWQoy4iBvMf2kjk9qxH/liahNFOdaFIWqr0QtcFWz0d7YcFqz vZOUfyzT1oZV19y9uVlkjBPfWy9Wht43nxFLPUK3YCCB8fcAfhB07c4gYBG2VyKWTXCV lSgngMNXEQZy48KyigX3qN8h+U82Uxae5SJgD1vqpepRRwJK4S9aCKGeaU3IdLk3ApuX m7Tg== X-Gm-Message-State: AOAM531UUNA203oGYJib6SmEKKFXJp5dogGyja1INoVwIURR5RKdORay B9ZpBZBQl+uoz8LykyxmNomfZDrN48lJgv8smQ== X-Google-Smtp-Source: ABdhPJxgwIRDwveYRMn6jZYEppdEHf6zMGiXAbdouv/bN5rkU0F3Reqsgn5ZoRJJoWKi0KbuJ4cps8DTxTVzu+nyrA== X-Received: from kaleshsingh.mtv.corp.google.com ([2620:15c:211:200:7091:8518:ec1e:93dc]) (user=kaleshsingh job=sendgmr) by 2002:a17:90a:1f4c:b0:1e6:6f77:c573 with SMTP id y12-20020a17090a1f4c00b001e66f77c573mr34893288pjy.17.1654620960558; Tue, 07 Jun 2022 09:56:00 -0700 (PDT) Date: Tue, 7 Jun 2022 09:50:46 -0700 In-Reply-To: <20220607165105.639716-1-kaleshsingh@google.com> Message-Id: <20220607165105.639716-5-kaleshsingh@google.com> Mime-Version: 1.0 References: <20220607165105.639716-1-kaleshsingh@google.com> X-Mailer: git-send-email 2.36.1.255.ge46751e96f-goog Subject: [PATCH v3 4/5] KVM: arm64: Allocate shared stacktrace pages From: Kalesh Singh To: mark.rutland@arm.com, broonie@kernel.org, maz@kernel.org Cc: will@kernel.org, qperret@google.com, tabba@google.com, surenb@google.com, tjmercier@google.com, kernel-team@android.com, Kalesh Singh , James Morse , Alexandru Elisei , Suzuki K Poulose , Catalin Marinas , Masami Hiramatsu , Alexei Starovoitov , "Madhavan T. Venkataraman" , Peter Zijlstra , Andrew Jones , Zenghui Yu , Keir Fraser , Kefeng Wang , Ard Biesheuvel , Oliver Upton , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220607_095603_035984_7E8DB4DC X-CRM114-Status: GOOD ( 17.98 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The nVHE hypervisor can use this shared area to dump its stacktrace addresses on hyp_panic(). Symbolization and printing the stacktrace can then be handled by the host in EL1 (done in a later patch in this series). Signed-off-by: Kalesh Singh --- arch/arm64/include/asm/kvm_asm.h | 1 + arch/arm64/kvm/arm.c | 34 ++++++++++++++++++++++++++++++++ arch/arm64/kvm/hyp/nvhe/setup.c | 11 +++++++++++ 3 files changed, 46 insertions(+) diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index 2e277f2ed671..ad31ac68264f 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -174,6 +174,7 @@ struct kvm_nvhe_init_params { unsigned long hcr_el2; unsigned long vttbr; unsigned long vtcr; + unsigned long stacktrace_hyp_va; }; /* Translate a kernel address @ptr into its equivalent linear mapping */ diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 400bb0fe2745..c0a936a7623d 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -50,6 +50,7 @@ DEFINE_STATIC_KEY_FALSE(kvm_protected_mode_initialized); DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector); static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page); +DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stacktrace_page); unsigned long kvm_arm_hyp_percpu_base[NR_CPUS]; DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params); @@ -1554,6 +1555,7 @@ static void cpu_prepare_hyp_mode(int cpu) tcr |= (idmap_t0sz & GENMASK(TCR_TxSZ_WIDTH - 1, 0)) << TCR_T0SZ_OFFSET; params->tcr_el2 = tcr; + params->stacktrace_hyp_va = kern_hyp_va(per_cpu(kvm_arm_hyp_stacktrace_page, cpu)); params->pgd_pa = kvm_mmu_get_httbr(); if (is_protected_kvm_enabled()) params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS; @@ -1845,6 +1847,7 @@ static void teardown_hyp_mode(void) free_hyp_pgds(); for_each_possible_cpu(cpu) { free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); + free_page(per_cpu(kvm_arm_hyp_stacktrace_page, cpu)); free_pages(kvm_arm_hyp_percpu_base[cpu], nvhe_percpu_order()); } } @@ -1936,6 +1939,23 @@ static int init_hyp_mode(void) per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page; } + /* + * Allocate stacktrace pages for Hypervisor-mode. + * This is used by the hypervisor to share its stacktrace + * with the host on a hyp_panic(). + */ + for_each_possible_cpu(cpu) { + unsigned long stacktrace_page; + + stacktrace_page = __get_free_page(GFP_KERNEL); + if (!stacktrace_page) { + err = -ENOMEM; + goto out_err; + } + + per_cpu(kvm_arm_hyp_stacktrace_page, cpu) = stacktrace_page; + } + /* * Allocate and initialize pages for Hypervisor-mode percpu regions. */ @@ -2043,6 +2063,20 @@ static int init_hyp_mode(void) params->stack_hyp_va = hyp_addr + (2 * PAGE_SIZE); } + /* + * Map the hyp stacktrace pages. + */ + for_each_possible_cpu(cpu) { + char *stacktrace_page = (char *)per_cpu(kvm_arm_hyp_stacktrace_page, cpu); + + err = create_hyp_mappings(stacktrace_page, stacktrace_page + PAGE_SIZE, + PAGE_HYP); + if (err) { + kvm_err("Cannot map hyp stacktrace page\n"); + goto out_err; + } + } + for_each_possible_cpu(cpu) { char *percpu_begin = (char *)kvm_arm_hyp_percpu_base[cpu]; char *percpu_end = percpu_begin + nvhe_percpu_size(); diff --git a/arch/arm64/kvm/hyp/nvhe/setup.c b/arch/arm64/kvm/hyp/nvhe/setup.c index e8d4ea2fcfa0..9b81bf2d40d7 100644 --- a/arch/arm64/kvm/hyp/nvhe/setup.c +++ b/arch/arm64/kvm/hyp/nvhe/setup.c @@ -135,6 +135,17 @@ static int recreate_hyp_mappings(phys_addr_t phys, unsigned long size, /* Update stack_hyp_va to end of the stack's private VA range */ params->stack_hyp_va = hyp_addr + (2 * PAGE_SIZE); + + /* + * Map the stacktrace pages as shared and transfer ownership to + * the hypervisor. + */ + prot = pkvm_mkstate(PAGE_HYP, PKVM_PAGE_SHARED_OWNED); + start = (void *)params->stacktrace_hyp_va; + end = start + PAGE_SIZE; + ret = pkvm_create_mappings(start, end, prot); + if (ret) + return ret; } /*