From nobody Sun Sep 7 13:33:51 2025 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CD3CBEB64DA for ; Tue, 18 Jul 2023 03:24:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229541AbjGRDYU (ORCPT ); Mon, 17 Jul 2023 23:24:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33120 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231207AbjGRDXq (ORCPT ); Mon, 17 Jul 2023 23:23:46 -0400 Received: from mail-oo1-xc34.google.com (mail-oo1-xc34.google.com [IPv6:2607:f8b0:4864:20::c34]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 85B78171B; Mon, 17 Jul 2023 20:23:22 -0700 (PDT) Received: by mail-oo1-xc34.google.com with SMTP id 006d021491bc7-5634d8d1db0so3225640eaf.0; Mon, 17 Jul 2023 20:23:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1689650601; x=1692242601; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=bSMrDEwxkhYrlz2QgyYImrZKuicJf1LqTrgFv+twk64=; b=PIBfVH4lx4su5LTNvllbFqSeHldg6NPwn0x1M9u78QkqGGgoCrJUuTKhbiBmLanV2u Z6xU5Pah2k+8BJYh88dh+wAN5FeQVK2yMK3ASi4KlH7n4MBBYfhamIbC7/r28vT6nA7J 5jp1p+JbC++/p0TmzVTUgMZjPBDrqLtHdNxHDtp15n07Mr0aHFcEmQJ3pyP9Ix23UaLK bKb7Lj0d5OzVPAZFgIAX9QY+bTDQhVOl1hQfesyeh+hbIuXTry1LL4dqKxoA3hgcbp+g k/nlAPoHdJV85JEbUhnJDVouKVzQ0DrB9y8oX8+5hbyytEhtfaGUqfRtso6uk4+zBoZP gzEQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689650601; x=1692242601; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=bSMrDEwxkhYrlz2QgyYImrZKuicJf1LqTrgFv+twk64=; b=faVJr7d9uCOdCZ1tKVViy7AhCFDO56PEhhwdgaiazlpzlpbJykg5p9Vl+bzAcxJm60 IPFm2hFmEdC1tYRi5elkOBLHFI64ylnHKUydaR634J2wFddvM5tlUrpWlJHtQmszacbo M2C2WWE6UMPvK5YW/UQtFPZCBAd870RWoMdxh606VXVh21/MHOAiZ8I0tU5kb48y0bRB TCJ7Dny5pXILhivwRKG/2IlkxYM2R7DElcD7/sYx37yhMl8rgRlH18GqXUbetrySGwnO gsL20m88pKrejKYtOC6JOeRQ2DePocn2Mvy7SHHLyRW/I9zdB9ZgLvK79d+wr0HbR7Jd wU7g== X-Gm-Message-State: ABy/qLYaYVoeDwdR/5V0nh6/0J1vVuwxtlJ6nedlZd93MycVdoFgZKP2 ROW5fta73DUVI08IKeC0hUg= X-Google-Smtp-Source: APBJJlHEeTZWvAn8Q9W86MaZ8eS7GKrzqZfkP3AsMB7N5Ek9MRV9jW2DJUAgCljsFOjJ2EeRyq3ijQ== X-Received: by 2002:aca:bb0b:0:b0:3a3:78dc:8c4c with SMTP id l11-20020acabb0b000000b003a378dc8c4cmr12856863oif.46.1689650601176; Mon, 17 Jul 2023 20:23:21 -0700 (PDT) Received: from ubuntu-Virtual-Machine.corp.microsoft.com ([2001:4898:80e8:37:c5e9:2003:6c97:8057]) by smtp.gmail.com with ESMTPSA id s92-20020a17090a2f6500b00263f41a655esm504040pjd.43.2023.07.17.20.23.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 Jul 2023 20:23:20 -0700 (PDT) From: Tianyu Lan To: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, daniel.lezcano@linaro.org, arnd@arndb.de, michael.h.kelley@microsoft.com Cc: Tianyu Lan , linux-arch@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, vkuznets@redhat.com, Michael Kelley Subject: [PATCH V3 8/9] x86/hyperv: Add smp support for SEV-SNP guest Date: Mon, 17 Jul 2023 23:23:02 -0400 Message-Id: <20230718032304.136888-9-ltykernel@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230718032304.136888-1-ltykernel@gmail.com> References: <20230718032304.136888-1-ltykernel@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Tianyu Lan In the AMD SEV-SNP guest, AP needs to be started up via sev es save area and Hyper-V requires to call HVCALL_START_VP hypercall to pass the gpa of sev es save area with AP's vp index and VTL(Virtual trust level) parameters. Override wakeup_secondary_cpu_64 callback with hv_snp_boot_ap. Reviewed-by: Michael Kelley Signed-off-by: Tianyu Lan --- arch/x86/hyperv/ivm.c | 95 +++++++++++++++++++++++++++++++ arch/x86/include/asm/mshyperv.h | 9 +++ arch/x86/kernel/cpu/mshyperv.c | 13 ++++- include/asm-generic/hyperv-tlfs.h | 1 + 4 files changed, 116 insertions(+), 2 deletions(-) diff --git a/arch/x86/hyperv/ivm.c b/arch/x86/hyperv/ivm.c index ede47c8264e0..2eda4e69849d 100644 --- a/arch/x86/hyperv/ivm.c +++ b/arch/x86/hyperv/ivm.c @@ -23,11 +23,15 @@ #include #include #include +#include =20 #ifdef CONFIG_AMD_MEM_ENCRYPT =20 #define GHCB_USAGE_HYPERV_CALL 1 =20 +static u8 ap_start_input_arg[PAGE_SIZE] __bss_decrypted __aligned(PAGE_SIZ= E); +static u8 ap_start_stack[PAGE_SIZE] __aligned(PAGE_SIZE); + union hv_ghcb { struct ghcb ghcb; struct { @@ -450,6 +454,97 @@ __init void hv_sev_init_mem_and_cpu(void) } } =20 +#define hv_populate_vmcb_seg(seg, gdtr_base) \ +do { \ + if (seg.selector) { \ + seg.base =3D 0; \ + seg.limit =3D HV_AP_SEGMENT_LIMIT; \ + seg.attrib =3D *(u16 *)(gdtr_base + seg.selector + 5); \ + seg.attrib =3D (seg.attrib & 0xFF) | ((seg.attrib >> 4) & 0xF00); \ + } \ +} while (0) \ + +int hv_snp_boot_ap(int cpu, unsigned long start_ip) +{ + struct sev_es_save_area *vmsa =3D (struct sev_es_save_area *) + __get_free_page(GFP_KERNEL | __GFP_ZERO); + struct desc_ptr gdtr; + u64 ret, rmp_adjust, retry =3D 5; + struct hv_enable_vp_vtl *start_vp_input; + unsigned long flags; + + native_store_gdt(&gdtr); + + vmsa->gdtr.base =3D gdtr.address; + vmsa->gdtr.limit =3D gdtr.size; + + asm volatile("movl %%es, %%eax;" : "=3Da" (vmsa->es.selector)); + hv_populate_vmcb_seg(vmsa->es, vmsa->gdtr.base); + + asm volatile("movl %%cs, %%eax;" : "=3Da" (vmsa->cs.selector)); + hv_populate_vmcb_seg(vmsa->cs, vmsa->gdtr.base); + + asm volatile("movl %%ss, %%eax;" : "=3Da" (vmsa->ss.selector)); + hv_populate_vmcb_seg(vmsa->ss, vmsa->gdtr.base); + + asm volatile("movl %%ds, %%eax;" : "=3Da" (vmsa->ds.selector)); + hv_populate_vmcb_seg(vmsa->ds, vmsa->gdtr.base); + + vmsa->efer =3D native_read_msr(MSR_EFER); + + asm volatile("movq %%cr4, %%rax;" : "=3Da" (vmsa->cr4)); + asm volatile("movq %%cr3, %%rax;" : "=3Da" (vmsa->cr3)); + asm volatile("movq %%cr0, %%rax;" : "=3Da" (vmsa->cr0)); + + vmsa->xcr0 =3D 1; + vmsa->g_pat =3D HV_AP_INIT_GPAT_DEFAULT; + vmsa->rip =3D (u64)secondary_startup_64_no_verify; + vmsa->rsp =3D (u64)&ap_start_stack[PAGE_SIZE]; + + /* + * Set the SNP-specific fields for this VMSA: + * VMPL level + * SEV_FEATURES (matches the SEV STATUS MSR right shifted 2 bits) + */ + vmsa->vmpl =3D 0; + vmsa->sev_features =3D sev_status >> 2; + + /* + * Running at VMPL0 allows the kernel to change the VMSA bit for a page + * using the RMPADJUST instruction. However, for the instruction to + * succeed it must target the permissions of a lesser privileged + * (higher numbered) VMPL level, so use VMPL1 (refer to the RMPADJUST + * instruction in the AMD64 APM Volume 3). + */ + rmp_adjust =3D RMPADJUST_VMSA_PAGE_BIT | 1; + ret =3D rmpadjust((unsigned long)vmsa, RMP_PG_SIZE_4K, + rmp_adjust); + if (ret !=3D 0) { + pr_err("RMPADJUST(%llx) failed: %llx\n", (u64)vmsa, ret); + return ret; + } + + local_irq_save(flags); + start_vp_input =3D + (struct hv_enable_vp_vtl *)ap_start_input_arg; + memset(start_vp_input, 0, sizeof(*start_vp_input)); + start_vp_input->partition_id =3D -1; + start_vp_input->vp_index =3D cpu; + start_vp_input->target_vtl.target_vtl =3D ms_hyperv.vtl; + *(u64 *)&start_vp_input->vp_context =3D __pa(vmsa) | 1; + + do { + ret =3D hv_do_hypercall(HVCALL_START_VP, + start_vp_input, NULL); + } while (hv_result(ret) =3D=3D HV_STATUS_TIME_OUT && retry--); + + local_irq_restore(flags); + + if (!hv_result_success(ret)) + pr_err("HvCallStartVirtualProcessor failed: %llx\n", ret); + return ret; +} + void __init hv_vtom_init(void) { /* diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyper= v.h index e57df590846a..c5a3c29fad01 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -65,6 +65,13 @@ struct memory_map_entry { u32 reserved; }; =20 +/* + * DEFAULT INIT GPAT and SEGMENT LIMIT value in struct VMSA + * to start AP in enlightened SEV guest. + */ +#define HV_AP_INIT_GPAT_DEFAULT 0x0007040600070406ULL +#define HV_AP_SEGMENT_LIMIT 0xffffffff + int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages); int hv_call_add_logical_proc(int node, u32 lp_index, u32 acpi_id); int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags); @@ -250,6 +257,7 @@ bool hv_ghcb_negotiate_protocol(void); void __noreturn hv_ghcb_terminate(unsigned int set, unsigned int reason); void hv_vtom_init(void); void hv_sev_init_mem_and_cpu(void); +int hv_snp_boot_ap(int cpu, unsigned long start_ip); #else static inline void hv_ghcb_msr_write(u64 msr, u64 value) {} static inline void hv_ghcb_msr_read(u64 msr, u64 *value) {} @@ -257,6 +265,7 @@ static inline bool hv_ghcb_negotiate_protocol(void) { r= eturn false; } static inline void hv_ghcb_terminate(unsigned int set, unsigned int reason= ) {} static inline void hv_vtom_init(void) {} static inline void hv_sev_init_mem_and_cpu(void) {} +static int hv_snp_boot_ap(int cpu, unsigned long start_ip) {} #endif =20 extern bool hv_isolation_type_snp(void); diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index d3bb921ee7fe..8e1d9ed6a1e0 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -295,6 +295,16 @@ static void __init hv_smp_prepare_cpus(unsigned int ma= x_cpus) =20 native_smp_prepare_cpus(max_cpus); =20 + /* + * Override wakeup_secondary_cpu_64 callback for SEV-SNP + * enlightened guest. + */ + if (hv_isolation_type_en_snp()) + apic->wakeup_secondary_cpu_64 =3D hv_snp_boot_ap; + + if (!hv_root_partition) + return; + #ifdef CONFIG_X86_64 for_each_present_cpu(i) { if (i =3D=3D 0) @@ -502,8 +512,7 @@ static void __init ms_hyperv_init_platform(void) =20 # ifdef CONFIG_SMP smp_ops.smp_prepare_boot_cpu =3D hv_smp_prepare_boot_cpu; - if (hv_root_partition) - smp_ops.smp_prepare_cpus =3D hv_smp_prepare_cpus; + smp_ops.smp_prepare_cpus =3D hv_smp_prepare_cpus; # endif =20 /* diff --git a/include/asm-generic/hyperv-tlfs.h b/include/asm-generic/hyperv= -tlfs.h index f4e4cc4f965f..fdac4a1714ec 100644 --- a/include/asm-generic/hyperv-tlfs.h +++ b/include/asm-generic/hyperv-tlfs.h @@ -223,6 +223,7 @@ enum HV_GENERIC_SET_FORMAT { #define HV_STATUS_INVALID_PORT_ID 17 #define HV_STATUS_INVALID_CONNECTION_ID 18 #define HV_STATUS_INSUFFICIENT_BUFFERS 19 +#define HV_STATUS_TIME_OUT 120 #define HV_STATUS_VTL_ALREADY_ENABLED 134 =20 /* --=20 2.25.1