From patchwork Mon Oct 25 12:21:10 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tianyu Lan X-Patchwork-Id: 12581707 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65412C433FE for ; Mon, 25 Oct 2021 12:22:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4DC98610A0 for ; Mon, 25 Oct 2021 12:22:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233394AbhJYMYW (ORCPT ); Mon, 25 Oct 2021 08:24:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38768 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233247AbhJYMXt (ORCPT ); Mon, 25 Oct 2021 08:23:49 -0400 Received: from mail-pf1-x433.google.com (mail-pf1-x433.google.com [IPv6:2607:f8b0:4864:20::433]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1ECD4C061229; Mon, 25 Oct 2021 05:21:27 -0700 (PDT) Received: by mail-pf1-x433.google.com with SMTP id 187so10550099pfc.10; Mon, 25 Oct 2021 05:21:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=+7pz2foD/4GwcDIE39vmWSuWuTwJleRXg4SRKQkhN+E=; b=AESlPeorHAIJn0wVvqn0Bv4CDXtMzlW0FjCvNlhqyF6ZeJf+jeKMOmkK+zhgQmYum7 5S4GI+yN/Vh7C0riiXRyi9TtNa11cdhW1GRp7+7Xj0CY2j439Sfkrhp40j0QFxX5p3P9 HQ1lCyM78JM0ZBe/PYgl/cK+1otfq5zUJ0vT12ouw5B8Fx8Z5HFuy5GBj/DpZlIzQQwi nbJiPo2UDd/Rwwqygf4r1IBggqUBj08RQhdkGYRxWEOVDdQNPUtViERVRClxmHS7KgQd pIgkDPzRFbG51vCat99NTMtSpzk/xQP6QUzGtRKIyEgdYZVwn7u39uGzkoKZxqsDPv/F 7L8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=+7pz2foD/4GwcDIE39vmWSuWuTwJleRXg4SRKQkhN+E=; b=cA7nWL02hf3seGyj2LOu+6GzI7V81cYPnEYXRU+e6UthpchJwkOcK8zz03QjA777e3 TQBA5LS+XNsDr1ISHwzWtDudCYwxVWepLlQwn/kpXDRl5AjNHS5Mzarc6KLD+4suhqkZ ENZwQDyMJl9M66sxMZeMlefKi7VToW29BjR5mK4jEWlXpWn3mqjFgGFkuqXEjMjZ4MhB KUs/dqKIfdyCexVwXkkd3//zfylFosVOfawqHWyVzQhpv1lWbJnxmEsIHJUTgnRp/kao hBH1QYTpkNcxLqgPEoK9O1ZKJBJ3S/IiNhUG9yi9A7JhOjwdpk3+x2yIquxW0siQNr4Y byOQ== X-Gm-Message-State: AOAM532jk1oESXBlMy1bo/o3Xk4SRDIy7PvsppHXB2LZSP0jtFqrjEbD U7Hx2tinF7xl/MOf78TjB8s= X-Google-Smtp-Source: ABdhPJxiQwKVDxPVQectkbll0gJHvEm/RE73L9RH9DkEJqD9OrwlNI/ZgmMNTcozf3GE7ND4UQUXsA== X-Received: by 2002:a62:5304:0:b0:44c:719c:a2c with SMTP id h4-20020a625304000000b0044c719c0a2cmr17538108pfb.13.1635164486657; Mon, 25 Oct 2021 05:21:26 -0700 (PDT) Received: from ubuntu-Virtual-Machine.corp.microsoft.com ([2001:4898:80e8:8:bcf6:9813:137f:2b6]) by smtp.gmail.com with ESMTPSA id mi11sm2786166pjb.5.2021.10.25.05.21.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 Oct 2021 05:21:26 -0700 (PDT) From: Tianyu Lan To: kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, dave.hansen@linux.intel.com, luto@kernel.org, peterz@infradead.org, davem@davemloft.net, kuba@kernel.org, gregkh@linuxfoundation.org, arnd@arndb.de, brijesh.singh@amd.com, jroedel@suse.de, mikelley@microsoft.com, Tianyu.Lan@microsoft.com, thomas.lendacky@amd.com, pgonda@google.com, akpm@linux-foundation.org, rppt@kernel.org, kirill.shutemov@linux.intel.com, saravanand@fb.com, aneesh.kumar@linux.ibm.com, sfr@canb.auug.org.au, david@redhat.com, michael.h.kelley@microsoft.com Cc: linux-arch@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, vkuznets@redhat.com, konrad.wilk@oracle.com, hch@lst.de, robin.murphy@arm.com, joro@8bytes.org, parri.andrea@gmail.com, dave.hansen@intel.com Subject: [PATCH V9 5/9] x86/sev-es: Expose sev_es_ghcb_hv_call() to call ghcb hv call out of sev code Date: Mon, 25 Oct 2021 08:21:10 -0400 Message-Id: <20211025122116.264793-6-ltykernel@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211025122116.264793-1-ltykernel@gmail.com> References: <20211025122116.264793-1-ltykernel@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Tianyu Lan Hyper-V needs to call ghcb hv call to write/read MSR in Isolation VM. So expose sev_es_ghcb_hv_call() to call it in the Hyper-V code. Hyper-V Isolation VM is unenlightened guests and run a paravisor in the VMPL0 for communicating and GHCB pages are being allocated and set up by that paravisor. Linux gets ghcb page pa via MSR_AMD64_SEV_ES_GHCB from paravisor and should not change it. Add set_ghcb_msr parameter for sev_es_ghcb_hv_call() and not set ghcb page pa when it's false. Reviewed-by: Michael Kelley Signed-off-by: Tianyu Lan --- Change since v8: - Remove sev_es_ghcb_hv_call() stub function. arch/x86/include/asm/sev.h | 5 +++++ arch/x86/kernel/sev-shared.c | 25 ++++++++++++++++--------- arch/x86/kernel/sev.c | 13 +++++++------ 3 files changed, 28 insertions(+), 15 deletions(-) diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h index fa5cd05d3b5b..e3576916215d 100644 --- a/arch/x86/include/asm/sev.h +++ b/arch/x86/include/asm/sev.h @@ -81,6 +81,11 @@ static __always_inline void sev_es_nmi_complete(void) __sev_es_nmi_complete(); } extern int __init sev_es_efi_map_ghcbs(pgd_t *pgd); +extern enum es_result sev_es_ghcb_hv_call(struct ghcb *ghcb, + bool set_ghcb_msr, + struct es_em_ctxt *ctxt, + u64 exit_code, u64 exit_info_1, + u64 exit_info_2); #else static inline void sev_es_ist_enter(struct pt_regs *regs) { } static inline void sev_es_ist_exit(void) { } diff --git a/arch/x86/kernel/sev-shared.c b/arch/x86/kernel/sev-shared.c index ea9abd69237e..e1863a6d76b8 100644 --- a/arch/x86/kernel/sev-shared.c +++ b/arch/x86/kernel/sev-shared.c @@ -124,10 +124,9 @@ static enum es_result verify_exception_info(struct ghcb *ghcb, struct es_em_ctxt return ES_VMM_ERROR; } -static enum es_result sev_es_ghcb_hv_call(struct ghcb *ghcb, - struct es_em_ctxt *ctxt, - u64 exit_code, u64 exit_info_1, - u64 exit_info_2) +enum es_result sev_es_ghcb_hv_call(struct ghcb *ghcb, bool set_ghcb_msr, + struct es_em_ctxt *ctxt, u64 exit_code, + u64 exit_info_1, u64 exit_info_2) { /* Fill in protocol and format specifiers */ ghcb->protocol_version = GHCB_PROTOCOL_MAX; @@ -137,7 +136,14 @@ static enum es_result sev_es_ghcb_hv_call(struct ghcb *ghcb, ghcb_set_sw_exit_info_1(ghcb, exit_info_1); ghcb_set_sw_exit_info_2(ghcb, exit_info_2); - sev_es_wr_ghcb_msr(__pa(ghcb)); + /* + * Hyper-V unenlightened guests use a paravisor for communicating and + * GHCB pages are being allocated and set up by that paravisor. Linux + * should not change the GHCB page's physical address. + */ + if (set_ghcb_msr) + sev_es_wr_ghcb_msr(__pa(ghcb)); + VMGEXIT(); return verify_exception_info(ghcb, ctxt); @@ -417,7 +423,7 @@ static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) */ sw_scratch = __pa(ghcb) + offsetof(struct ghcb, shared_buffer); ghcb_set_sw_scratch(ghcb, sw_scratch); - ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_IOIO, + ret = sev_es_ghcb_hv_call(ghcb, true, ctxt, SVM_EXIT_IOIO, exit_info_1, exit_info_2); if (ret != ES_OK) return ret; @@ -459,7 +465,8 @@ static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) ghcb_set_rax(ghcb, rax); - ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_IOIO, exit_info_1, 0); + ret = sev_es_ghcb_hv_call(ghcb, true, ctxt, + SVM_EXIT_IOIO, exit_info_1, 0); if (ret != ES_OK) return ret; @@ -490,7 +497,7 @@ static enum es_result vc_handle_cpuid(struct ghcb *ghcb, /* xgetbv will cause #GP - use reset value for xcr0 */ ghcb_set_xcr0(ghcb, 1); - ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_CPUID, 0, 0); + ret = sev_es_ghcb_hv_call(ghcb, true, ctxt, SVM_EXIT_CPUID, 0, 0); if (ret != ES_OK) return ret; @@ -515,7 +522,7 @@ static enum es_result vc_handle_rdtsc(struct ghcb *ghcb, bool rdtscp = (exit_code == SVM_EXIT_RDTSCP); enum es_result ret; - ret = sev_es_ghcb_hv_call(ghcb, ctxt, exit_code, 0, 0); + ret = sev_es_ghcb_hv_call(ghcb, true, ctxt, exit_code, 0, 0); if (ret != ES_OK) return ret; diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c index a6895e440bc3..bb62a1d15d6c 100644 --- a/arch/x86/kernel/sev.c +++ b/arch/x86/kernel/sev.c @@ -648,7 +648,8 @@ static enum es_result vc_handle_msr(struct ghcb *ghcb, struct es_em_ctxt *ctxt) ghcb_set_rdx(ghcb, regs->dx); } - ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_MSR, exit_info_1, 0); + ret = sev_es_ghcb_hv_call(ghcb, true, ctxt, SVM_EXIT_MSR, + exit_info_1, 0); if ((ret == ES_OK) && (!exit_info_1)) { regs->ax = ghcb->save.rax; @@ -867,7 +868,7 @@ static enum es_result vc_do_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt, ghcb_set_sw_scratch(ghcb, ghcb_pa + offsetof(struct ghcb, shared_buffer)); - return sev_es_ghcb_hv_call(ghcb, ctxt, exit_code, exit_info_1, exit_info_2); + return sev_es_ghcb_hv_call(ghcb, true, ctxt, exit_code, exit_info_1, exit_info_2); } static enum es_result vc_handle_mmio_twobyte_ops(struct ghcb *ghcb, @@ -1117,7 +1118,7 @@ static enum es_result vc_handle_dr7_write(struct ghcb *ghcb, /* Using a value of 0 for ExitInfo1 means RAX holds the value */ ghcb_set_rax(ghcb, val); - ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_WRITE_DR7, 0, 0); + ret = sev_es_ghcb_hv_call(ghcb, true, ctxt, SVM_EXIT_WRITE_DR7, 0, 0); if (ret != ES_OK) return ret; @@ -1147,7 +1148,7 @@ static enum es_result vc_handle_dr7_read(struct ghcb *ghcb, static enum es_result vc_handle_wbinvd(struct ghcb *ghcb, struct es_em_ctxt *ctxt) { - return sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_WBINVD, 0, 0); + return sev_es_ghcb_hv_call(ghcb, true, ctxt, SVM_EXIT_WBINVD, 0, 0); } static enum es_result vc_handle_rdpmc(struct ghcb *ghcb, struct es_em_ctxt *ctxt) @@ -1156,7 +1157,7 @@ static enum es_result vc_handle_rdpmc(struct ghcb *ghcb, struct es_em_ctxt *ctxt ghcb_set_rcx(ghcb, ctxt->regs->cx); - ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_RDPMC, 0, 0); + ret = sev_es_ghcb_hv_call(ghcb, true, ctxt, SVM_EXIT_RDPMC, 0, 0); if (ret != ES_OK) return ret; @@ -1197,7 +1198,7 @@ static enum es_result vc_handle_vmmcall(struct ghcb *ghcb, if (x86_platform.hyper.sev_es_hcall_prepare) x86_platform.hyper.sev_es_hcall_prepare(ghcb, ctxt->regs); - ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_VMMCALL, 0, 0); + ret = sev_es_ghcb_hv_call(ghcb, true, ctxt, SVM_EXIT_VMMCALL, 0, 0); if (ret != ES_OK) return ret;