| Message ID | 20230403174406.4180472-4-ltykernel@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | x86/hyperv/sev: Add AMD sev-snp enlightened guest support on hyperv | expand |
From: Tianyu Lan <ltykernel@gmail.com> Sent: Monday, April 3, 2023 10:44 AM > > sev-snp guest provides vtl(Virtual Trust Level) and > get it from hyperv hvcall via HVCALL_GET_VP_REGISTERS. > Set target vtl in the VMBus init message. > > Signed-off-by: Tianyu Lan <tiala@microsoft.com> > --- > Change since RFC v3: > * Use the standard helper functions to check hypercall result > * Fix coding style > > Change since RFC v2: > * Rename get_current_vtl() to get_vtl() > * Fix some coding style issues > --- > arch/x86/hyperv/hv_init.c | 36 ++++++++++++++++++++++++++++++ > arch/x86/include/asm/hyperv-tlfs.h | 7 ++++++ > drivers/hv/connection.c | 1 + > include/asm-generic/mshyperv.h | 2 ++ > include/linux/hyperv.h | 4 ++-- > 5 files changed, 48 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c > index 9f3e2d71d015..7602db5ad4aa 100644 > --- a/arch/x86/hyperv/hv_init.c > +++ b/arch/x86/hyperv/hv_init.c > @@ -384,6 +384,40 @@ static void __init hv_get_partition_id(void) > local_irq_restore(flags); > } > > +static u8 __init get_vtl(void) > +{ > + u64 control = HV_HYPERCALL_REP_COMP_1 | HVCALL_GET_VP_REGISTERS; > + struct hv_get_vp_registers_input *input; > + struct hv_get_vp_registers_output *output; > + u64 vtl = 0; > + u64 ret; > + unsigned long flags; > + > + local_irq_save(flags); > + input = *(struct hv_get_vp_registers_input **)this_cpu_ptr(hyperv_pcpu_input_arg); The cast to struct hv_get_vp_registers_input isn't needed here. Just do: input = *this_cpu_ptr(hyperv_pcpu_input_arg); I know we have other code that references hyperv_pcpu_input_arg with a more complicated code sequence, but it's really not necessary. At some point, we should go back and clean those up, but let's not add any new cases. :-) > + output = (struct hv_get_vp_registers_output *)input; > + if (!input) { > + local_irq_restore(flags); > + goto done; > + } > + > + memset(input, 0, sizeof(*input) + sizeof(input->element[0])); Use struct_size() to calculate the size of a structure plus a trailing variable size array. > + input->header.partitionid = HV_PARTITION_ID_SELF; > + input->header.vpindex = HV_VP_INDEX_SELF; > + input->header.inputvtl = 0; > + input->element[0].name0 = HV_X64_REGISTER_VSM_VP_STATUS; > + > + ret = hv_do_hypercall(control, input, output); > + if (hv_result_success(ret)) > + vtl = output->as64.low & HV_X64_VTL_MASK; > + else > + pr_err("Hyper-V: failed to get VTL!"); Let's include the hypercall status in the failure message. If a failure ever happens, we will really want to know what that status is. :-) > + local_irq_restore(flags); > + > +done: > + return vtl; > +} > + > /* > * This function is to be invoked early in the boot sequence after the > * hypervisor has been detected. > @@ -512,6 +546,8 @@ void __init hyperv_init(void) > /* Query the VMs extended capability once, so that it can be cached. */ > hv_query_ext_cap(0); > > + /* Find the VTL */ > + ms_hyperv.vtl = get_vtl(); > return; > > clean_guest_os_id: > diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h > index b4fb75bd1013..3d3f014976e8 100644 > --- a/arch/x86/include/asm/hyperv-tlfs.h > +++ b/arch/x86/include/asm/hyperv-tlfs.h > @@ -301,6 +301,13 @@ enum hv_isolation_type { > #define HV_X64_MSR_TIME_REF_COUNT HV_REGISTER_TIME_REF_COUNT > #define HV_X64_MSR_REFERENCE_TSC HV_REGISTER_REFERENCE_TSC > > +/* > + * Registers are only accessible via HVCALL_GET_VP_REGISTERS hvcall and > + * there is not associated MSR address. > + */ > +#define HV_X64_REGISTER_VSM_VP_STATUS 0x000D0003 > +#define HV_X64_VTL_MASK GENMASK(3, 0) > + > /* Hyper-V memory host visibility */ > enum hv_mem_host_visibility { > VMBUS_PAGE_NOT_VISIBLE = 0, > diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c > index f670cfd2e056..e4c39f4016ad 100644 > --- a/drivers/hv/connection.c > +++ b/drivers/hv/connection.c > @@ -98,6 +98,7 @@ int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version) > */ > if (version >= VERSION_WIN10_V5) { > msg->msg_sint = VMBUS_MESSAGE_SINT; > + msg->msg_vtl = ms_hyperv.vtl; > vmbus_connection.msg_conn_id = VMBUS_MESSAGE_CONNECTION_ID_4; > } else { > msg->interrupt_page = virt_to_phys(vmbus_connection.int_page); > diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h > index afcd9ae9588c..f91fb06634f0 100644 > --- a/include/asm-generic/mshyperv.h > +++ b/include/asm-generic/mshyperv.h > @@ -48,6 +48,7 @@ struct ms_hyperv_info { > }; > }; > u64 shared_gpa_boundary; > + u8 vtl; > }; > extern struct ms_hyperv_info ms_hyperv; > extern bool hv_nested; > @@ -58,6 +59,7 @@ extern void * __percpu *hyperv_pcpu_output_arg; > extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr); > extern u64 hv_do_fast_hypercall8(u16 control, u64 input8); > extern bool hv_isolation_type_snp(void); > +extern bool hv_isolation_type_en_snp(void); Why is this extern added as part of this patch? There are not any new references to hv_isolation_type_en_snp() that would need it. > > /* Helper functions that provide a consistent pattern for checking Hyper-V hypercall status. */ > static inline int hv_result(u64 status) > diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h > index bfbc37ce223b..1f2bfec4abde 100644 > --- a/include/linux/hyperv.h > +++ b/include/linux/hyperv.h > @@ -665,8 +665,8 @@ struct vmbus_channel_initiate_contact { > u64 interrupt_page; > struct { > u8 msg_sint; > - u8 padding1[3]; > - u32 padding2; > + u8 msg_vtl; > + u8 reserved[6]; > }; > }; > u64 monitor_page1; > -- > 2.25.1
On 4/12/2023 10:24 PM, Michael Kelley (LINUX) wrote: >> +static u8 __init get_vtl(void) >> +{ >> + u64 control = HV_HYPERCALL_REP_COMP_1 | HVCALL_GET_VP_REGISTERS; >> + struct hv_get_vp_registers_input *input; >> + struct hv_get_vp_registers_output *output; >> + u64 vtl = 0; >> + u64 ret; >> + unsigned long flags; >> + >> + local_irq_save(flags); >> + input = *(struct hv_get_vp_registers_input **)this_cpu_ptr(hyperv_pcpu_input_arg); > The cast to struct hv_get_vp_registers_input isn't needed here. Just do: > > input = *this_cpu_ptr(hyperv_pcpu_input_arg); > > I know we have other code that references hyperv_pcpu_input_arg with a more > complicated code sequence, but it's really not necessary. At some point, we > should go back and clean those up, but let's not add any new cases.
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index 9f3e2d71d015..7602db5ad4aa 100644 --- a/arch/x86/hyperv/hv_init.c +++ b/arch/x86/hyperv/hv_init.c @@ -384,6 +384,40 @@ static void __init hv_get_partition_id(void) local_irq_restore(flags); } +static u8 __init get_vtl(void) +{ + u64 control = HV_HYPERCALL_REP_COMP_1 | HVCALL_GET_VP_REGISTERS; + struct hv_get_vp_registers_input *input; + struct hv_get_vp_registers_output *output; + u64 vtl = 0; + u64 ret; + unsigned long flags; + + local_irq_save(flags); + input = *(struct hv_get_vp_registers_input **)this_cpu_ptr(hyperv_pcpu_input_arg); + output = (struct hv_get_vp_registers_output *)input; + if (!input) { + local_irq_restore(flags); + goto done; + } + + memset(input, 0, sizeof(*input) + sizeof(input->element[0])); + input->header.partitionid = HV_PARTITION_ID_SELF; + input->header.vpindex = HV_VP_INDEX_SELF; + input->header.inputvtl = 0; + input->element[0].name0 = HV_X64_REGISTER_VSM_VP_STATUS; + + ret = hv_do_hypercall(control, input, output); + if (hv_result_success(ret)) + vtl = output->as64.low & HV_X64_VTL_MASK; + else + pr_err("Hyper-V: failed to get VTL!"); + local_irq_restore(flags); + +done: + return vtl; +} + /* * This function is to be invoked early in the boot sequence after the * hypervisor has been detected. @@ -512,6 +546,8 @@ void __init hyperv_init(void) /* Query the VMs extended capability once, so that it can be cached. */ hv_query_ext_cap(0); + /* Find the VTL */ + ms_hyperv.vtl = get_vtl(); return; clean_guest_os_id: diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h index b4fb75bd1013..3d3f014976e8 100644 --- a/arch/x86/include/asm/hyperv-tlfs.h +++ b/arch/x86/include/asm/hyperv-tlfs.h @@ -301,6 +301,13 @@ enum hv_isolation_type { #define HV_X64_MSR_TIME_REF_COUNT HV_REGISTER_TIME_REF_COUNT #define HV_X64_MSR_REFERENCE_TSC HV_REGISTER_REFERENCE_TSC +/* + * Registers are only accessible via HVCALL_GET_VP_REGISTERS hvcall and + * there is not associated MSR address. + */ +#define HV_X64_REGISTER_VSM_VP_STATUS 0x000D0003 +#define HV_X64_VTL_MASK GENMASK(3, 0) + /* Hyper-V memory host visibility */ enum hv_mem_host_visibility { VMBUS_PAGE_NOT_VISIBLE = 0, diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index f670cfd2e056..e4c39f4016ad 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -98,6 +98,7 @@ int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version) */ if (version >= VERSION_WIN10_V5) { msg->msg_sint = VMBUS_MESSAGE_SINT; + msg->msg_vtl = ms_hyperv.vtl; vmbus_connection.msg_conn_id = VMBUS_MESSAGE_CONNECTION_ID_4; } else { msg->interrupt_page = virt_to_phys(vmbus_connection.int_page); diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h index afcd9ae9588c..f91fb06634f0 100644 --- a/include/asm-generic/mshyperv.h +++ b/include/asm-generic/mshyperv.h @@ -48,6 +48,7 @@ struct ms_hyperv_info { }; }; u64 shared_gpa_boundary; + u8 vtl; }; extern struct ms_hyperv_info ms_hyperv; extern bool hv_nested; @@ -58,6 +59,7 @@ extern void * __percpu *hyperv_pcpu_output_arg; extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr); extern u64 hv_do_fast_hypercall8(u16 control, u64 input8); extern bool hv_isolation_type_snp(void); +extern bool hv_isolation_type_en_snp(void); /* Helper functions that provide a consistent pattern for checking Hyper-V hypercall status. */ static inline int hv_result(u64 status) diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index bfbc37ce223b..1f2bfec4abde 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -665,8 +665,8 @@ struct vmbus_channel_initiate_contact { u64 interrupt_page; struct { u8 msg_sint; - u8 padding1[3]; - u32 padding2; + u8 msg_vtl; + u8 reserved[6]; }; }; u64 monitor_page1;