A TDX guest uses the GHCI call rather than hv_hypercall_pg.
In hv_do_hypercall(), Hyper-V requires that the input/output addresses
must have the vTOM bit set. With current Hyper-V, the bit for TDX is
bit 47, which is saved into ms_hyperv.shared_gpa_boundary() in
ms_hyperv_init_platform().
arch/x86/include/asm/mshyperv.h: hv_do_hypercall() needs
"struct ms_hyperv_info", which is defined in
include/asm-generic/mshyperv.h, which can't be included in
arch/x86/include/asm/mshyperv.h because include/asm-generic/mshyperv.h
has vmbus_signal_eom() -> hv_set_register(), which is defined in
arch/x86/include/asm/mshyperv.h.
Break this circular dependency by introducing a new header file
for "struct ms_hyperv_info".
Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
---
MAINTAINERS | 1 +
arch/x86/hyperv/hv_init.c | 8 ++++++++
arch/x86/include/asm/mshyperv.h | 24 ++++++++++++++++++++++-
arch/x86/kernel/cpu/mshyperv.c | 2 ++
include/asm-generic/ms_hyperv_info.h | 29 ++++++++++++++++++++++++++++
include/asm-generic/mshyperv.h | 24 +----------------------
6 files changed, 64 insertions(+), 24 deletions(-)
create mode 100644 include/asm-generic/ms_hyperv_info.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 256f03904987..455ecaf188fe 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9537,6 +9537,7 @@ F: drivers/scsi/storvsc_drv.c
F: drivers/uio/uio_hv_generic.c
F: drivers/video/fbdev/hyperv_fb.c
F: include/asm-generic/hyperv-tlfs.h
+F: include/asm-generic/ms_hyperv_info.h
F: include/asm-generic/mshyperv.h
F: include/clocksource/hyperv_timer.h
F: include/linux/hyperv.h
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index 89954490af93..05682c4e327f 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -432,6 +432,10 @@ void __init hyperv_init(void)
/* Hyper-V requires to write guest os id via ghcb in SNP IVM. */
hv_ghcb_msr_write(HV_X64_MSR_GUEST_OS_ID, guest_id);
+ /* A TDX guest uses the GHCI call rather than hv_hypercall_pg. */
+ if (hv_isolation_type_tdx())
+ goto skip_hypercall_pg_init;
+
hv_hypercall_pg = __vmalloc_node_range(PAGE_SIZE, 1, VMALLOC_START,
VMALLOC_END, GFP_KERNEL, PAGE_KERNEL_ROX,
VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
@@ -471,6 +475,7 @@ void __init hyperv_init(void)
wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
}
+skip_hypercall_pg_init:
/*
* hyperv_init() is called before LAPIC is initialized: see
* apic_intr_mode_init() -> x86_platform.apic_post_init() and
@@ -606,6 +611,9 @@ bool hv_is_hyperv_initialized(void)
if (x86_hyper_type != X86_HYPER_MS_HYPERV)
return false;
+ /* A TDX guest uses the GHCI call rather than hv_hypercall_pg. */
+ if (hv_isolation_type_tdx())
+ return true;
/*
* Verify that earlier initialization succeeded by checking
* that the hypercall page is setup
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index 9d593ab2be26..650b4fae2fd8 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -9,7 +9,7 @@
#include <asm/hyperv-tlfs.h>
#include <asm/nospec-branch.h>
#include <asm/paravirt.h>
-#include <asm/mshyperv.h>
+#include <asm-generic/ms_hyperv_info.h>
union hv_ghcb;
@@ -48,6 +48,18 @@ static inline u64 hv_do_hypercall(u64 control, void *input, void *output)
u64 hv_status;
#ifdef CONFIG_X86_64
+#if CONFIG_INTEL_TDX_GUEST
+ if (hv_isolation_type_tdx()) {
+ if (input_address)
+ input_address += ms_hyperv.shared_gpa_boundary;
+
+ if (output_address)
+ output_address += ms_hyperv.shared_gpa_boundary;
+
+ return __tdx_ms_hv_hypercall(control, output_address,
+ input_address);
+ }
+#endif
if (!hv_hypercall_pg)
return U64_MAX;
@@ -85,6 +97,11 @@ static inline u64 hv_do_fast_hypercall8(u16 code, u64 input1)
u64 hv_status, control = (u64)code | HV_HYPERCALL_FAST_BIT;
#ifdef CONFIG_X86_64
+#if CONFIG_INTEL_TDX_GUEST
+ if (hv_isolation_type_tdx())
+ return __tdx_ms_hv_hypercall(control, 0, input1);
+#endif
+
{
__asm__ __volatile__(CALL_NOSPEC
: "=a" (hv_status), ASM_CALL_CONSTRAINT,
@@ -116,6 +133,11 @@ static inline u64 hv_do_fast_hypercall16(u16 code, u64 input1, u64 input2)
u64 hv_status, control = (u64)code | HV_HYPERCALL_FAST_BIT;
#ifdef CONFIG_X86_64
+#if CONFIG_INTEL_TDX_GUEST
+ if (hv_isolation_type_tdx())
+ return __tdx_ms_hv_hypercall(control, input2, input1);
+#endif
+
{
__asm__ __volatile__("mov %4, %%r8\n"
CALL_NOSPEC
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 9ad0b0abf0e0..dddccdbc5526 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -349,6 +349,8 @@ static void __init ms_hyperv_init_platform(void)
case HV_ISOLATION_TYPE_TDX:
static_branch_enable(&isolation_type_tdx);
+
+ ms_hyperv.shared_gpa_boundary = cc_mkdec(0);
break;
default:
diff --git a/include/asm-generic/ms_hyperv_info.h b/include/asm-generic/ms_hyperv_info.h
new file mode 100644
index 000000000000..734583dfea99
--- /dev/null
+++ b/include/asm-generic/ms_hyperv_info.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _ASM_GENERIC_MS_HYPERV_INFO_H
+#define _ASM_GENERIC_MS_HYPERV_INFO_H
+
+struct ms_hyperv_info {
+ u32 features;
+ u32 priv_high;
+ u32 misc_features;
+ u32 hints;
+ u32 nested_features;
+ u32 max_vp_index;
+ u32 max_lp_index;
+ u32 isolation_config_a;
+ union {
+ u32 isolation_config_b;
+ struct {
+ u32 cvm_type : 4;
+ u32 reserved1 : 1;
+ u32 shared_gpa_boundary_active : 1;
+ u32 shared_gpa_boundary_bits : 6;
+ u32 reserved2 : 20;
+ };
+ };
+ u64 shared_gpa_boundary;
+};
+extern struct ms_hyperv_info ms_hyperv;
+
+#endif
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index bfb9eb9d7215..2ae3e4e4256b 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -25,29 +25,7 @@
#include <linux/nmi.h>
#include <asm/ptrace.h>
#include <asm/hyperv-tlfs.h>
-
-struct ms_hyperv_info {
- u32 features;
- u32 priv_high;
- u32 misc_features;
- u32 hints;
- u32 nested_features;
- u32 max_vp_index;
- u32 max_lp_index;
- u32 isolation_config_a;
- union {
- u32 isolation_config_b;
- struct {
- u32 cvm_type : 4;
- u32 reserved1 : 1;
- u32 shared_gpa_boundary_active : 1;
- u32 shared_gpa_boundary_bits : 6;
- u32 reserved2 : 20;
- };
- };
- u64 shared_gpa_boundary;
-};
-extern struct ms_hyperv_info ms_hyperv;
+#include <asm-generic/ms_hyperv_info.h>
extern void * __percpu *hyperv_pcpu_input_arg;
extern void * __percpu *hyperv_pcpu_output_arg;
--
2.25.1
