| Message ID | 20231115071519.2864957-19-xiaoyao.li@intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | QEMU Guest memfd + QEMU TDX support | expand |
On Wed, Nov 15, 2023 at 02:14:27AM -0500, Xiaoyao Li wrote: > KVM provides TDX capabilities via sub command KVM_TDX_CAPABILITIES of > IOCTL(KVM_MEMORY_ENCRYPT_OP). Get the capabilities when initializing > TDX context. It will be used to validate user's setting later. > > Since there is no interface reporting how many cpuid configs contains in > KVM_TDX_CAPABILITIES, QEMU chooses to try starting with a known number > and abort when it exceeds KVM_MAX_CPUID_ENTRIES. > > Besides, introduce the interfaces to invoke TDX "ioctls" at different > scope (KVM, VM and VCPU) in preparation. > > Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> > --- > Changes in v3: > - rename __tdx_ioctl() to tdx_ioctl_internal() > - Pass errp in get_tdx_capabilities(); > > changes in v2: > - Make the error message more clear; > > changes in v1: > - start from nr_cpuid_configs = 6 for the loop; > - stop the loop when nr_cpuid_configs exceeds KVM_MAX_CPUID_ENTRIES; > --- > target/i386/kvm/kvm.c | 2 - > target/i386/kvm/kvm_i386.h | 2 + > target/i386/kvm/tdx.c | 102 ++++++++++++++++++++++++++++++++++++- > 3 files changed, 103 insertions(+), 3 deletions(-) > > diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c > index 7abcdebb1452..28e60c5ea4a7 100644 > --- a/target/i386/kvm/kvm.c > +++ b/target/i386/kvm/kvm.c > @@ -1687,8 +1687,6 @@ static int hyperv_init_vcpu(X86CPU *cpu) > > static Error *invtsc_mig_blocker; > > -#define KVM_MAX_CPUID_ENTRIES 100 > - > static void kvm_init_xsave(CPUX86State *env) > { > if (has_xsave2) { > diff --git a/target/i386/kvm/kvm_i386.h b/target/i386/kvm/kvm_i386.h > index 55fb25fa8e2e..c3ef46a97a7b 100644 > --- a/target/i386/kvm/kvm_i386.h > +++ b/target/i386/kvm/kvm_i386.h > @@ -13,6 +13,8 @@ > > #include "sysemu/kvm.h" > > +#define KVM_MAX_CPUID_ENTRIES 100 > + > #ifdef CONFIG_KVM > > #define kvm_pit_in_kernel() \ > diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c > index 621a05beeb4e..cb0040187b27 100644 > --- a/target/i386/kvm/tdx.c > +++ b/target/i386/kvm/tdx.c > @@ -12,17 +12,117 @@ > */ > > #include "qemu/osdep.h" > +#include "qemu/error-report.h" > #include "qapi/error.h" > #include "qom/object_interfaces.h" > +#include "sysemu/kvm.h" > > #include "hw/i386/x86.h" > +#include "kvm_i386.h" > #include "tdx.h" > > +static struct kvm_tdx_capabilities *tdx_caps; > + > +enum tdx_ioctl_level{ > + TDX_PLATFORM_IOCTL, > + TDX_VM_IOCTL, > + TDX_VCPU_IOCTL, > +}; > + > +static int tdx_ioctl_internal(void *state, enum tdx_ioctl_level level, int cmd_id, > + __u32 flags, void *data) > +{ > + struct kvm_tdx_cmd tdx_cmd; Add ' = {}' to initialize to all-zeros, avoiding the explicit memset call > + int r; > + > + memset(&tdx_cmd, 0x0, sizeof(tdx_cmd)); > + > + tdx_cmd.id = cmd_id; > + tdx_cmd.flags = flags; > + tdx_cmd.data = (__u64)(unsigned long)data; > + > + switch (level) { > + case TDX_PLATFORM_IOCTL: > + r = kvm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd); > + break; > + case TDX_VM_IOCTL: > + r = kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd); > + break; > + case TDX_VCPU_IOCTL: > + r = kvm_vcpu_ioctl(state, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd); > + break; > + default: > + error_report("Invalid tdx_ioctl_level %d", level); > + exit(1); > + } > + > + return r; > +} > + > +static inline int tdx_platform_ioctl(int cmd_id, __u32 flags, void *data) > +{ > + return tdx_ioctl_internal(NULL, TDX_PLATFORM_IOCTL, cmd_id, flags, data); > +} > + > +static inline int tdx_vm_ioctl(int cmd_id, __u32 flags, void *data) > +{ > + return tdx_ioctl_internal(NULL, TDX_VM_IOCTL, cmd_id, flags, data); > +} > + > +static inline int tdx_vcpu_ioctl(void *vcpu_fd, int cmd_id, __u32 flags, > + void *data) > +{ > + return tdx_ioctl_internal(vcpu_fd, TDX_VCPU_IOCTL, cmd_id, flags, data); > +} > + > +static int get_tdx_capabilities(Error **errp) > +{ > + struct kvm_tdx_capabilities *caps; > + /* 1st generation of TDX reports 6 cpuid configs */ > + int nr_cpuid_configs = 6; > + size_t size; > + int r; > + > + do { > + size = sizeof(struct kvm_tdx_capabilities) + > + nr_cpuid_configs * sizeof(struct kvm_tdx_cpuid_config); > + caps = g_malloc0(size); > + caps->nr_cpuid_configs = nr_cpuid_configs; > + > + r = tdx_vm_ioctl(KVM_TDX_CAPABILITIES, 0, caps); > + if (r == -E2BIG) { > + g_free(caps); > + nr_cpuid_configs *= 2; > + if (nr_cpuid_configs > KVM_MAX_CPUID_ENTRIES) { > + error_setg(errp, "%s: KVM TDX seems broken that number of CPUID " > + "entries in kvm_tdx_capabilities exceeds limit %d", > + __func__, KVM_MAX_CPUID_ENTRIES); > + return r; > + } > + } else if (r < 0) { > + g_free(caps); > + error_setg_errno(errp, -r, "%s: KVM_TDX_CAPABILITIES failed", __func__); > + return r; > + } > + } > + while (r == -E2BIG); > + > + tdx_caps = caps; > + > + return 0; > +} > + > int tdx_kvm_init(MachineState *ms, Error **errp) > { > + int r = 0; > + > ms->require_guest_memfd = true; > > - return 0; > + if (!tdx_caps) { > + r = get_tdx_capabilities(errp); > + } > + > + return r; > } > > /* tdx guest */ > -- > 2.34.1 > With regards, Daniel
On Wed, Nov 15, 2023 at 02:14:27AM -0500, Xiaoyao Li <xiaoyao.li@intel.com> wrote: > KVM provides TDX capabilities via sub command KVM_TDX_CAPABILITIES of > IOCTL(KVM_MEMORY_ENCRYPT_OP). Get the capabilities when initializing > TDX context. It will be used to validate user's setting later. > > Since there is no interface reporting how many cpuid configs contains in > KVM_TDX_CAPABILITIES, QEMU chooses to try starting with a known number > and abort when it exceeds KVM_MAX_CPUID_ENTRIES. > > Besides, introduce the interfaces to invoke TDX "ioctls" at different > scope (KVM, VM and VCPU) in preparation. > > Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> > --- > Changes in v3: > - rename __tdx_ioctl() to tdx_ioctl_internal() > - Pass errp in get_tdx_capabilities(); > > changes in v2: > - Make the error message more clear; > > changes in v1: > - start from nr_cpuid_configs = 6 for the loop; > - stop the loop when nr_cpuid_configs exceeds KVM_MAX_CPUID_ENTRIES; > --- > target/i386/kvm/kvm.c | 2 - > target/i386/kvm/kvm_i386.h | 2 + > target/i386/kvm/tdx.c | 102 ++++++++++++++++++++++++++++++++++++- > 3 files changed, 103 insertions(+), 3 deletions(-) > > diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c > index 7abcdebb1452..28e60c5ea4a7 100644 > --- a/target/i386/kvm/kvm.c > +++ b/target/i386/kvm/kvm.c > @@ -1687,8 +1687,6 @@ static int hyperv_init_vcpu(X86CPU *cpu) > > static Error *invtsc_mig_blocker; > > -#define KVM_MAX_CPUID_ENTRIES 100 > - > static void kvm_init_xsave(CPUX86State *env) > { > if (has_xsave2) { > diff --git a/target/i386/kvm/kvm_i386.h b/target/i386/kvm/kvm_i386.h > index 55fb25fa8e2e..c3ef46a97a7b 100644 > --- a/target/i386/kvm/kvm_i386.h > +++ b/target/i386/kvm/kvm_i386.h > @@ -13,6 +13,8 @@ > > #include "sysemu/kvm.h" > > +#define KVM_MAX_CPUID_ENTRIES 100 > + > #ifdef CONFIG_KVM > > #define kvm_pit_in_kernel() \ > diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c > index 621a05beeb4e..cb0040187b27 100644 > --- a/target/i386/kvm/tdx.c > +++ b/target/i386/kvm/tdx.c > @@ -12,17 +12,117 @@ > */ > > #include "qemu/osdep.h" > +#include "qemu/error-report.h" > #include "qapi/error.h" > #include "qom/object_interfaces.h" > +#include "sysemu/kvm.h" > > #include "hw/i386/x86.h" > +#include "kvm_i386.h" > #include "tdx.h" > > +static struct kvm_tdx_capabilities *tdx_caps; > + > +enum tdx_ioctl_level{ > + TDX_PLATFORM_IOCTL, > + TDX_VM_IOCTL, > + TDX_VCPU_IOCTL, > +}; > + > +static int tdx_ioctl_internal(void *state, enum tdx_ioctl_level level, int cmd_id, > + __u32 flags, void *data) > +{ > + struct kvm_tdx_cmd tdx_cmd; > + int r; > + > + memset(&tdx_cmd, 0x0, sizeof(tdx_cmd)); > + > + tdx_cmd.id = cmd_id; > + tdx_cmd.flags = flags; > + tdx_cmd.data = (__u64)(unsigned long)data; > + > + switch (level) { > + case TDX_PLATFORM_IOCTL: > + r = kvm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd); > + break; > + case TDX_VM_IOCTL: > + r = kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd); > + break; > + case TDX_VCPU_IOCTL: > + r = kvm_vcpu_ioctl(state, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd); > + break; > + default: > + error_report("Invalid tdx_ioctl_level %d", level); > + exit(1); > + } > + > + return r; > +} > + > +static inline int tdx_platform_ioctl(int cmd_id, __u32 flags, void *data) > +{ > + return tdx_ioctl_internal(NULL, TDX_PLATFORM_IOCTL, cmd_id, flags, data); > +} > + > +static inline int tdx_vm_ioctl(int cmd_id, __u32 flags, void *data) > +{ > + return tdx_ioctl_internal(NULL, TDX_VM_IOCTL, cmd_id, flags, data); > +} > + > +static inline int tdx_vcpu_ioctl(void *vcpu_fd, int cmd_id, __u32 flags, > + void *data) > +{ > + return tdx_ioctl_internal(vcpu_fd, TDX_VCPU_IOCTL, cmd_id, flags, data); > +} As all of ioctl variants aren't used yet, we can split out them. An independent patch to define ioctl functions. > + > +static int get_tdx_capabilities(Error **errp) > +{ > + struct kvm_tdx_capabilities *caps; > + /* 1st generation of TDX reports 6 cpuid configs */ > + int nr_cpuid_configs = 6; > + size_t size; > + int r; > + > + do { > + size = sizeof(struct kvm_tdx_capabilities) + > + nr_cpuid_configs * sizeof(struct kvm_tdx_cpuid_config); > + caps = g_malloc0(size); > + caps->nr_cpuid_configs = nr_cpuid_configs; > + > + r = tdx_vm_ioctl(KVM_TDX_CAPABILITIES, 0, caps); > + if (r == -E2BIG) { > + g_free(caps); > + nr_cpuid_configs *= 2; g_realloc()? Maybe a matter of preference. Other than this, it looks good to me.
On 11/18/2023 5:18 AM, Isaku Yamahata wrote: > On Wed, Nov 15, 2023 at 02:14:27AM -0500, > Xiaoyao Li <xiaoyao.li@intel.com> wrote: > >> KVM provides TDX capabilities via sub command KVM_TDX_CAPABILITIES of >> IOCTL(KVM_MEMORY_ENCRYPT_OP). Get the capabilities when initializing >> TDX context. It will be used to validate user's setting later. >> >> Since there is no interface reporting how many cpuid configs contains in >> KVM_TDX_CAPABILITIES, QEMU chooses to try starting with a known number >> and abort when it exceeds KVM_MAX_CPUID_ENTRIES. >> >> Besides, introduce the interfaces to invoke TDX "ioctls" at different >> scope (KVM, VM and VCPU) in preparation. >> >> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> >> --- >> Changes in v3: >> - rename __tdx_ioctl() to tdx_ioctl_internal() >> - Pass errp in get_tdx_capabilities(); >> >> changes in v2: >> - Make the error message more clear; >> >> changes in v1: >> - start from nr_cpuid_configs = 6 for the loop; >> - stop the loop when nr_cpuid_configs exceeds KVM_MAX_CPUID_ENTRIES; >> --- >> target/i386/kvm/kvm.c | 2 - >> target/i386/kvm/kvm_i386.h | 2 + >> target/i386/kvm/tdx.c | 102 ++++++++++++++++++++++++++++++++++++- >> 3 files changed, 103 insertions(+), 3 deletions(-) >> >> diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c >> index 7abcdebb1452..28e60c5ea4a7 100644 >> --- a/target/i386/kvm/kvm.c >> +++ b/target/i386/kvm/kvm.c >> @@ -1687,8 +1687,6 @@ static int hyperv_init_vcpu(X86CPU *cpu) >> >> static Error *invtsc_mig_blocker; >> >> -#define KVM_MAX_CPUID_ENTRIES 100 >> - >> static void kvm_init_xsave(CPUX86State *env) >> { >> if (has_xsave2) { >> diff --git a/target/i386/kvm/kvm_i386.h b/target/i386/kvm/kvm_i386.h >> index 55fb25fa8e2e..c3ef46a97a7b 100644 >> --- a/target/i386/kvm/kvm_i386.h >> +++ b/target/i386/kvm/kvm_i386.h >> @@ -13,6 +13,8 @@ >> >> #include "sysemu/kvm.h" >> >> +#define KVM_MAX_CPUID_ENTRIES 100 >> + >> #ifdef CONFIG_KVM >> >> #define kvm_pit_in_kernel() \ >> diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c >> index 621a05beeb4e..cb0040187b27 100644 >> --- a/target/i386/kvm/tdx.c >> +++ b/target/i386/kvm/tdx.c >> @@ -12,17 +12,117 @@ >> */ >> >> #include "qemu/osdep.h" >> +#include "qemu/error-report.h" >> #include "qapi/error.h" >> #include "qom/object_interfaces.h" >> +#include "sysemu/kvm.h" >> >> #include "hw/i386/x86.h" >> +#include "kvm_i386.h" >> #include "tdx.h" >> >> +static struct kvm_tdx_capabilities *tdx_caps; >> + >> +enum tdx_ioctl_level{ >> + TDX_PLATFORM_IOCTL, >> + TDX_VM_IOCTL, >> + TDX_VCPU_IOCTL, >> +}; >> + >> +static int tdx_ioctl_internal(void *state, enum tdx_ioctl_level level, int cmd_id, >> + __u32 flags, void *data) >> +{ >> + struct kvm_tdx_cmd tdx_cmd; >> + int r; >> + >> + memset(&tdx_cmd, 0x0, sizeof(tdx_cmd)); >> + >> + tdx_cmd.id = cmd_id; >> + tdx_cmd.flags = flags; >> + tdx_cmd.data = (__u64)(unsigned long)data; >> + >> + switch (level) { >> + case TDX_PLATFORM_IOCTL: >> + r = kvm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd); >> + break; >> + case TDX_VM_IOCTL: >> + r = kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd); >> + break; >> + case TDX_VCPU_IOCTL: >> + r = kvm_vcpu_ioctl(state, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd); >> + break; >> + default: >> + error_report("Invalid tdx_ioctl_level %d", level); >> + exit(1); >> + } >> + >> + return r; >> +} >> + >> +static inline int tdx_platform_ioctl(int cmd_id, __u32 flags, void *data) >> +{ >> + return tdx_ioctl_internal(NULL, TDX_PLATFORM_IOCTL, cmd_id, flags, data); >> +} >> + >> +static inline int tdx_vm_ioctl(int cmd_id, __u32 flags, void *data) >> +{ >> + return tdx_ioctl_internal(NULL, TDX_VM_IOCTL, cmd_id, flags, data); >> +} >> + >> +static inline int tdx_vcpu_ioctl(void *vcpu_fd, int cmd_id, __u32 flags, >> + void *data) >> +{ >> + return tdx_ioctl_internal(vcpu_fd, TDX_VCPU_IOCTL, cmd_id, flags, data); >> +} > > As all of ioctl variants aren't used yet, we can split out them. No. tdx_vm_ioctl() is used right below. I can remove the tdx_platform_ioctl() because its sole user, KVM_TDX_CAPABILITIES, changed to vm scope. > An independent > patch to define ioctl functions. > > >> + >> +static int get_tdx_capabilities(Error **errp) >> +{ >> + struct kvm_tdx_capabilities *caps; >> + /* 1st generation of TDX reports 6 cpuid configs */ >> + int nr_cpuid_configs = 6; >> + size_t size; >> + int r; >> + >> + do { >> + size = sizeof(struct kvm_tdx_capabilities) + >> + nr_cpuid_configs * sizeof(struct kvm_tdx_cpuid_config); >> + caps = g_malloc0(size); >> + caps->nr_cpuid_configs = nr_cpuid_configs; >> + >> + r = tdx_vm_ioctl(KVM_TDX_CAPABILITIES, 0, caps); >> + if (r == -E2BIG) { >> + g_free(caps); >> + nr_cpuid_configs *= 2; > > g_realloc()? Maybe a matter of preference. I would like to keep the current code unless strong objection from maintainers. > Other than this, it looks good to me.
On 11/15/2023 6:54 PM, Daniel P. Berrangé wrote: >> +static int tdx_ioctl_internal(void *state, enum tdx_ioctl_level level, int cmd_id, >> + __u32 flags, void *data) >> +{ >> + struct kvm_tdx_cmd tdx_cmd; > Add ' = {}' to initialize to all-zeros, avoiding the explicit > memset call thanks for the suggestion. Will do it in the next version.
diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index 7abcdebb1452..28e60c5ea4a7 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -1687,8 +1687,6 @@ static int hyperv_init_vcpu(X86CPU *cpu) static Error *invtsc_mig_blocker; -#define KVM_MAX_CPUID_ENTRIES 100 - static void kvm_init_xsave(CPUX86State *env) { if (has_xsave2) { diff --git a/target/i386/kvm/kvm_i386.h b/target/i386/kvm/kvm_i386.h index 55fb25fa8e2e..c3ef46a97a7b 100644 --- a/target/i386/kvm/kvm_i386.h +++ b/target/i386/kvm/kvm_i386.h @@ -13,6 +13,8 @@ #include "sysemu/kvm.h" +#define KVM_MAX_CPUID_ENTRIES 100 + #ifdef CONFIG_KVM #define kvm_pit_in_kernel() \ diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c index 621a05beeb4e..cb0040187b27 100644 --- a/target/i386/kvm/tdx.c +++ b/target/i386/kvm/tdx.c @@ -12,17 +12,117 @@ */ #include "qemu/osdep.h" +#include "qemu/error-report.h" #include "qapi/error.h" #include "qom/object_interfaces.h" +#include "sysemu/kvm.h" #include "hw/i386/x86.h" +#include "kvm_i386.h" #include "tdx.h" +static struct kvm_tdx_capabilities *tdx_caps; + +enum tdx_ioctl_level{ + TDX_PLATFORM_IOCTL, + TDX_VM_IOCTL, + TDX_VCPU_IOCTL, +}; + +static int tdx_ioctl_internal(void *state, enum tdx_ioctl_level level, int cmd_id, + __u32 flags, void *data) +{ + struct kvm_tdx_cmd tdx_cmd; + int r; + + memset(&tdx_cmd, 0x0, sizeof(tdx_cmd)); + + tdx_cmd.id = cmd_id; + tdx_cmd.flags = flags; + tdx_cmd.data = (__u64)(unsigned long)data; + + switch (level) { + case TDX_PLATFORM_IOCTL: + r = kvm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd); + break; + case TDX_VM_IOCTL: + r = kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd); + break; + case TDX_VCPU_IOCTL: + r = kvm_vcpu_ioctl(state, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd); + break; + default: + error_report("Invalid tdx_ioctl_level %d", level); + exit(1); + } + + return r; +} + +static inline int tdx_platform_ioctl(int cmd_id, __u32 flags, void *data) +{ + return tdx_ioctl_internal(NULL, TDX_PLATFORM_IOCTL, cmd_id, flags, data); +} + +static inline int tdx_vm_ioctl(int cmd_id, __u32 flags, void *data) +{ + return tdx_ioctl_internal(NULL, TDX_VM_IOCTL, cmd_id, flags, data); +} + +static inline int tdx_vcpu_ioctl(void *vcpu_fd, int cmd_id, __u32 flags, + void *data) +{ + return tdx_ioctl_internal(vcpu_fd, TDX_VCPU_IOCTL, cmd_id, flags, data); +} + +static int get_tdx_capabilities(Error **errp) +{ + struct kvm_tdx_capabilities *caps; + /* 1st generation of TDX reports 6 cpuid configs */ + int nr_cpuid_configs = 6; + size_t size; + int r; + + do { + size = sizeof(struct kvm_tdx_capabilities) + + nr_cpuid_configs * sizeof(struct kvm_tdx_cpuid_config); + caps = g_malloc0(size); + caps->nr_cpuid_configs = nr_cpuid_configs; + + r = tdx_vm_ioctl(KVM_TDX_CAPABILITIES, 0, caps); + if (r == -E2BIG) { + g_free(caps); + nr_cpuid_configs *= 2; + if (nr_cpuid_configs > KVM_MAX_CPUID_ENTRIES) { + error_setg(errp, "%s: KVM TDX seems broken that number of CPUID " + "entries in kvm_tdx_capabilities exceeds limit %d", + __func__, KVM_MAX_CPUID_ENTRIES); + return r; + } + } else if (r < 0) { + g_free(caps); + error_setg_errno(errp, -r, "%s: KVM_TDX_CAPABILITIES failed", __func__); + return r; + } + } + while (r == -E2BIG); + + tdx_caps = caps; + + return 0; +} + int tdx_kvm_init(MachineState *ms, Error **errp) { + int r = 0; + ms->require_guest_memfd = true; - return 0; + if (!tdx_caps) { + r = get_tdx_capabilities(errp); + } + + return r; } /* tdx guest */
KVM provides TDX capabilities via sub command KVM_TDX_CAPABILITIES of IOCTL(KVM_MEMORY_ENCRYPT_OP). Get the capabilities when initializing TDX context. It will be used to validate user's setting later. Since there is no interface reporting how many cpuid configs contains in KVM_TDX_CAPABILITIES, QEMU chooses to try starting with a known number and abort when it exceeds KVM_MAX_CPUID_ENTRIES. Besides, introduce the interfaces to invoke TDX "ioctls" at different scope (KVM, VM and VCPU) in preparation. Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> --- Changes in v3: - rename __tdx_ioctl() to tdx_ioctl_internal() - Pass errp in get_tdx_capabilities(); changes in v2: - Make the error message more clear; changes in v1: - start from nr_cpuid_configs = 6 for the loop; - stop the loop when nr_cpuid_configs exceeds KVM_MAX_CPUID_ENTRIES; --- target/i386/kvm/kvm.c | 2 - target/i386/kvm/kvm_i386.h | 2 + target/i386/kvm/tdx.c | 102 ++++++++++++++++++++++++++++++++++++- 3 files changed, 103 insertions(+), 3 deletions(-)