| Message ID | 20230501085726.544209-4-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 |
On Mon, 1 May 2023 04:57:13 -0400 Tianyu Lan <ltykernel@gmail.com> wrote: > From: Tianyu Lan <tiala@microsoft.com> > > 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 v4: > * Use struct_size to calculate array size. > * Fix some coding style > > 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 | 1 + > include/linux/hyperv.h | 4 ++-- > 5 files changed, 47 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c > index 9f3e2d71d015..331b855314b7 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 = *this_cpu_ptr(hyperv_pcpu_input_arg); > + output = (struct hv_get_vp_registers_output *)input; === > + if (!input) { > + local_irq_restore(flags); > + goto done; > + } > + === Is this really necessary? drivers/hv/hv_common.c: hyperv_pcpu_input_arg = alloc_percpu(void *); BUG_ON(!hyperv_pcpu_input_arg); > + memset(input, 0, struct_size(input, element, 1)); > + 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! %lld", ret); > + 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 cea95dcd27c2..4bf0b315b0ce 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 5978e9dbc286..02b54f85dc60 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 402a8c1c202d..3052130ba4ef 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; > 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;
On 5/2/2023 12:30 PM, Zhi Wang wrote: > On Mon, 1 May 2023 04:57:13 -0400 > Tianyu Lan <ltykernel@gmail.com> wrote: > >> From: Tianyu Lan <tiala@microsoft.com> >> >> 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 v4: >> * Use struct_size to calculate array size. >> * Fix some coding style >> >> 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 | 1 + >> include/linux/hyperv.h | 4 ++-- >> 5 files changed, 47 insertions(+), 2 deletions(-) >> >> diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c >> index 9f3e2d71d015..331b855314b7 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 = *this_cpu_ptr(hyperv_pcpu_input_arg); >> + output = (struct hv_get_vp_registers_output *)input; > > === >> + if (!input) { >> + local_irq_restore(flags); >> + goto done; >> + } >> + > === > Is this really necessary? > > drivers/hv/hv_common.c: > > hyperv_pcpu_input_arg = alloc_percpu(void *); > BUG_ON(!hyperv_pcpu_input_arg); > > Hi Zhi: The hyperv_pcpu_input_arg is a point to address of input arg pages and these pages are allocated in the hv_common_cpu_init(). If it failed to allocate these pages, the value pointed by hyperv_pcpu_input_arg will be NULL.
On Thu, 4 May 2023 08:38:46 -0700 Tianyu Lan <ltykernel@gmail.com> wrote: > On 5/2/2023 12:30 PM, Zhi Wang wrote: > > On Mon, 1 May 2023 04:57:13 -0400 > > Tianyu Lan <ltykernel@gmail.com> wrote: > > > >> From: Tianyu Lan <tiala@microsoft.com> > >> > >> 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 v4: > >> * Use struct_size to calculate array size. > >> * Fix some coding style > >> > >> 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 | 1 + > >> include/linux/hyperv.h | 4 ++-- > >> 5 files changed, 47 insertions(+), 2 deletions(-) > >> > >> diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c > >> index 9f3e2d71d015..331b855314b7 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 = *this_cpu_ptr(hyperv_pcpu_input_arg); > >> + output = (struct hv_get_vp_registers_output *)input; > > > > === > >> + if (!input) { > >> + local_irq_restore(flags); > >> + goto done; > >> + } > >> + > > === > > Is this really necessary? > > > > drivers/hv/hv_common.c: > > > > hyperv_pcpu_input_arg = alloc_percpu(void *); > > BUG_ON(!hyperv_pcpu_input_arg); > > > > > > Hi Zhi: > The hyperv_pcpu_input_arg is a point to address of input arg > pages and these pages are allocated in the hv_common_cpu_init(). If > it failed to allocate these pages, the value pointed by > hyperv_pcpu_input_arg will be NULL. > Sorry, it seems my email editor dropped some text. I was wondering that if the check above is necessary as there is a BUG_ON() when allocating hyperv_pcpu_input_arg. So when coming to get_vtl(), the hyperv_pcpu_input_arg should not be NULL. (Guarded by the BUG_ON() in the allocation)?
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index 9f3e2d71d015..331b855314b7 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 = *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, struct_size(input, element, 1)); + 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! %lld", ret); + 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 cea95dcd27c2..4bf0b315b0ce 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 5978e9dbc286..02b54f85dc60 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 402a8c1c202d..3052130ba4ef 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; 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;