From: Tianyu Lan <ltykernel@xxxxxxxxx> Sent: Saturday, January 21, 2023 6:46 PM > > The wakeup_secondary_cpu callback was populated with wakeup_ > cpu_via_vmgexit() which doesn't work for Hyper-V. Override it > with Hyper-V specific hook which uses HVCALL_START_VIRTUAL_ > PROCESSOR hvcall to start AP with vmsa data structure. > > Signed-off-by: Tianyu Lan <tiala@xxxxxxxxxxxxx> > --- > Change since RFC v2: > * Add helper function to initialize segment > * Fix some coding style > --- > arch/x86/include/asm/mshyperv.h | 2 + > arch/x86/include/asm/sev.h | 13 ++++ > arch/x86/include/asm/svm.h | 47 +++++++++++++ > arch/x86/kernel/cpu/mshyperv.c | 112 ++++++++++++++++++++++++++++-- > include/asm-generic/hyperv-tlfs.h | 19 +++++ > 5 files changed, 189 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h > index 7266d71d30d6..c69051eec0e1 100644 > --- a/arch/x86/include/asm/mshyperv.h > +++ b/arch/x86/include/asm/mshyperv.h > @@ -203,6 +203,8 @@ struct irq_domain *hv_create_pci_msi_domain(void); > int hv_map_ioapic_interrupt(int ioapic_id, bool level, int vcpu, int vector, > struct hv_interrupt_entry *entry); > int hv_unmap_ioapic_interrupt(int ioapic_id, struct hv_interrupt_entry *entry); > +int hv_set_mem_host_visibility(unsigned long addr, int numpages, bool visible); > +int hv_snp_boot_ap(int cpu, unsigned long start_ip); > > #ifdef CONFIG_AMD_MEM_ENCRYPT > void hv_ghcb_msr_write(u64 msr, u64 value); > diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h > index ebc271bb6d8e..e34aaf730220 100644 > --- a/arch/x86/include/asm/sev.h > +++ b/arch/x86/include/asm/sev.h > @@ -86,6 +86,19 @@ extern bool handle_vc_boot_ghcb(struct pt_regs *regs); > > #define RMPADJUST_VMSA_PAGE_BIT BIT(16) > > +union sev_rmp_adjust { > + u64 as_uint64; > + struct { > + unsigned long target_vmpl : 8; > + unsigned long enable_read : 1; > + unsigned long enable_write : 1; > + unsigned long enable_user_execute : 1; > + unsigned long enable_kernel_execute : 1; > + unsigned long reserved1 : 4; > + unsigned long vmsa : 1; > + }; > +}; > + > /* SNP Guest message request */ > struct snp_req_data { > unsigned long req_gpa; > diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h > index cb1ee53ad3b1..f8b321a11ee4 100644 > --- a/arch/x86/include/asm/svm.h > +++ b/arch/x86/include/asm/svm.h > @@ -336,6 +336,53 @@ struct vmcb_save_area { > u64 last_excp_to; > u8 reserved_0x298[72]; > u32 spec_ctrl; /* Guest version of SPEC_CTRL at 0x2E0 */ > + u8 reserved_7b[4]; > + u32 pkru; > + u8 reserved_7a[20]; > + u64 reserved_8; /* rax already available at 0x01f8 */ > + u64 rcx; > + u64 rdx; > + u64 rbx; > + u64 reserved_9; /* rsp already available at 0x01d8 */ > + u64 rbp; > + u64 rsi; > + u64 rdi; > + u64 r8; > + u64 r9; > + u64 r10; > + u64 r11; > + u64 r12; > + u64 r13; > + u64 r14; > + u64 r15; > + u8 reserved_10[16]; > + u64 sw_exit_code; > + u64 sw_exit_info_1; > + u64 sw_exit_info_2; > + u64 sw_scratch; > + union { > + u64 sev_features; > + struct { > + u64 sev_feature_snp : 1; > + u64 sev_feature_vtom : 1; > + u64 sev_feature_reflectvc : 1; > + u64 sev_feature_restrict_injection : 1; > + u64 sev_feature_alternate_injection : 1; > + u64 sev_feature_full_debug : 1; > + u64 sev_feature_reserved1 : 1; > + u64 sev_feature_snpbtb_isolation : 1; > + u64 sev_feature_resrved2 : 56; > + }; > + }; > + u64 vintr_ctrl; > + u64 guest_error_code; > + u64 virtual_tom; > + u64 tlb_id; > + u64 pcpu_id; > + u64 event_inject; > + u64 xcr0; > + u8 valid_bitmap[16]; > + u64 x87_state_gpa; > } __packed; > > /* Save area definition for SEV-ES and SEV-SNP guests */ > diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c > index 197c8f2ec4eb..9d547751a1a7 100644 > --- a/arch/x86/kernel/cpu/mshyperv.c > +++ b/arch/x86/kernel/cpu/mshyperv.c > @@ -39,6 +39,13 @@ > #include <asm/realmode.h> > #include <asm/e820/api.h> > > +/* > + * 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 If these values are defined by Hyper-V, they should probably go in hyperv-tlfs.h. > + > /* Is Linux running as the root partition? */ > bool hv_root_partition; > struct ms_hyperv_info ms_hyperv; > @@ -230,6 +237,94 @@ static void __init hv_smp_prepare_boot_cpu(void) > #endif > } > > +static u8 ap_start_input_arg[PAGE_SIZE] __bss_decrypted __aligned(PAGE_SIZE); > +static u8 ap_start_stack[PAGE_SIZE] __aligned(PAGE_SIZE); > + > +#define hv_populate_vmcb_seg(seg, gdtr_base) \ > +do { \ > + if (seg.selector) { \ > + seg.base = 0; \ > + seg.limit = HV_AP_SEGMENT_LIMIT; \ > + seg.attrib = *(u16 *)(gdtr_base + seg.selector + 5); \ > + seg.attrib = (seg.attrib & 0xFF) | ((seg.attrib >> 4) & 0xF00); \ > + } \ > +} while (0) \ > + > +int hv_snp_boot_ap(int cpu, unsigned long start_ip) > +{ > + struct vmcb_save_area *vmsa = (struct vmcb_save_area *) > + __get_free_page(GFP_KERNEL | __GFP_ZERO); > + struct desc_ptr gdtr; > + u64 ret, retry = 5; > + struct hv_start_virtual_processor_input *start_vp_input; > + union sev_rmp_adjust rmp_adjust; > + unsigned long flags; > + > + native_store_gdt(&gdtr); > + > + vmsa->gdtr.base = gdtr.address; > + vmsa->gdtr.limit = gdtr.size; > + > + asm volatile("movl %%es, %%eax;" : "=a" (vmsa->es.selector)); > + hv_populate_vmcb_seg(vmsa->es, vmsa->gdtr.base); > + > + asm volatile("movl %%cs, %%eax;" : "=a" (vmsa->cs.selector)); > + hv_populate_vmcb_seg(vmsa->cs, vmsa->gdtr.base); > + > + asm volatile("movl %%ss, %%eax;" : "=a" (vmsa->ss.selector)); > + hv_populate_vmcb_seg(vmsa->ss, vmsa->gdtr.base); > + > + asm volatile("movl %%ds, %%eax;" : "=a" (vmsa->ds.selector)); > + hv_populate_vmcb_seg(vmsa->ds, vmsa->gdtr.base); > + > + vmsa->efer = native_read_msr(MSR_EFER); > + > + asm volatile("movq %%cr4, %%rax;" : "=a" (vmsa->cr4)); > + asm volatile("movq %%cr3, %%rax;" : "=a" (vmsa->cr3)); > + asm volatile("movq %%cr0, %%rax;" : "=a" (vmsa->cr0)); > + > + vmsa->xcr0 = 1; > + vmsa->g_pat = HV_AP_INIT_GPAT_DEFAULT; > + vmsa->rip = (u64)secondary_startup_64_no_verify; > + vmsa->rsp = (u64)&ap_start_stack[PAGE_SIZE]; > + > + vmsa->sev_feature_snp = 1; > + vmsa->sev_feature_restrict_injection = 1; > + > + rmp_adjust.as_uint64 = 0; > + rmp_adjust.target_vmpl = 1; > + rmp_adjust.vmsa = 1; > + ret = rmpadjust((unsigned long)vmsa, RMP_PG_SIZE_4K, > + rmp_adjust.as_uint64); > + if (ret != 0) { > + pr_err("RMPADJUST(%llx) failed: %llx\n", (u64)vmsa, ret); > + return ret; > + } > + > + local_irq_save(flags); > + start_vp_input = > + (struct hv_start_virtual_processor_input *)ap_start_input_arg; > + memset(start_vp_input, 0, sizeof(*start_vp_input)); > + start_vp_input->partitionid = -1; > + start_vp_input->vpindex = cpu; > + start_vp_input->targetvtl = ms_hyperv.vtl; > + *(u64 *)&start_vp_input->context[0] = __pa(vmsa) | 1; > + > + do { > + ret = hv_do_hypercall(HVCALL_START_VIRTUAL_PROCESSOR, > + start_vp_input, NULL); > + } while (hv_result(ret) == HV_STATUS_TIME_OUT && retry--); > + > + if (!hv_result_success(ret)) { > + pr_err("HvCallStartVirtualProcessor failed: %llx\n", ret); > + goto done; > + } > + > +done: > + local_irq_restore(flags); > + return ret; > +} > + Like a comment in an earlier patch, I'm wondering if the bulk of this code could move to ivm.c, to avoid overloading mshyperv.c. > static void __init hv_smp_prepare_cpus(unsigned int max_cpus) > { > #ifdef CONFIG_X86_64 > @@ -239,6 +334,16 @@ static void __init hv_smp_prepare_cpus(unsigned int max_cpus) > > native_smp_prepare_cpus(max_cpus); > > + /* > + * Override wakeup_secondary_cpu callback for SEV-SNP > + * enlightened guest. > + */ > + if (hv_isolation_type_en_snp()) > + apic->wakeup_secondary_cpu = hv_snp_boot_ap; > + > + if (!hv_root_partition) > + return; > + > #ifdef CONFIG_X86_64 > for_each_present_cpu(i) { > if (i == 0) > @@ -475,8 +580,7 @@ static void __init ms_hyperv_init_platform(void) > > # ifdef CONFIG_SMP > smp_ops.smp_prepare_boot_cpu = hv_smp_prepare_boot_cpu; > - if (hv_root_partition) > - smp_ops.smp_prepare_cpus = hv_smp_prepare_cpus; > + smp_ops.smp_prepare_cpus = hv_smp_prepare_cpus; > # endif > > /* > @@ -501,7 +605,7 @@ static void __init ms_hyperv_init_platform(void) > if (!(ms_hyperv.features & HV_ACCESS_TSC_INVARIANT)) > mark_tsc_unstable("running on Hyper-V"); > > - if (isolation_type_en_snp()) { > + if (hv_isolation_type_en_snp()) { Also a bug fix to an earlier patch in this series. > /* > * Hyper-V enlightened snp guest boots kernel > * directly without bootloader and so roms, > @@ -511,7 +615,7 @@ static void __init ms_hyperv_init_platform(void) > x86_platform.legacy.rtc = 0; > x86_platform.set_wallclock = set_rtc_noop; > x86_platform.get_wallclock = get_rtc_noop; > - x86_platform.legacy.reserve_bios_regions = x86_init_noop; > + x86_platform.legacy.reserve_bios_regions = 0; This looks like a bug fix to Patch 8 of the series. It should be fixed in patch 8. > x86_init.resources.probe_roms = x86_init_noop; > x86_init.resources.reserve_resources = x86_init_noop; > x86_init.mpparse.find_smp_config = x86_init_noop; > diff --git a/include/asm-generic/hyperv-tlfs.h b/include/asm-generic/hyperv-tlfs.h > index c1cc3ec36ad5..3d7c67be9f56 100644 > --- a/include/asm-generic/hyperv-tlfs.h > +++ b/include/asm-generic/hyperv-tlfs.h > @@ -148,6 +148,7 @@ union hv_reference_tsc_msr { > #define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST 0x0003 > #define HVCALL_NOTIFY_LONG_SPIN_WAIT 0x0008 > #define HVCALL_SEND_IPI 0x000b > +#define HVCALL_ENABLE_VP_VTL 0x000f > #define HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX 0x0013 > #define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX 0x0014 > #define HVCALL_SEND_IPI_EX 0x0015 > @@ -165,6 +166,7 @@ union hv_reference_tsc_msr { > #define HVCALL_MAP_DEVICE_INTERRUPT 0x007c > #define HVCALL_UNMAP_DEVICE_INTERRUPT 0x007d > #define HVCALL_RETARGET_INTERRUPT 0x007e > +#define HVCALL_START_VIRTUAL_PROCESSOR 0x0099 > #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE 0x00af > #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_LIST 0x00b0 > #define HVCALL_MODIFY_SPARSE_GPA_PAGE_HOST_VISIBILITY 0x00db > @@ -219,6 +221,7 @@ 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 0x78 > > /* > * The Hyper-V TimeRefCount register and the TSC > @@ -778,6 +781,22 @@ struct hv_input_unmap_device_interrupt { > struct hv_interrupt_entry interrupt_entry; > } __packed; > > +struct hv_enable_vp_vtl_input { > + u64 partitionid; > + u32 vpindex; > + u8 targetvtl; > + u8 padding[3]; > + u8 context[0xe0]; > +} __packed; > + > +struct hv_start_virtual_processor_input { > + u64 partitionid; > + u32 vpindex; > + u8 targetvtl; > + u8 padding[3]; > + u8 context[0xe0]; > +} __packed; > + > #define HV_SOURCE_SHADOW_NONE 0x0 > #define HV_SOURCE_SHADOW_BRIDGE_BUS_RANGE 0x1 > > -- > 2.25.1