x86/hyperv: Remove hv_isolation_type_en_snp

In ms_hyperv_init_platform(), do not distinguish between a SNP VM with
the paravisor and a SNP VM without the paravisor.

Replace hv_isolation_type_en_snp() with
!ms_hyperv.paravisor_present && hv_isolation_type_snp().

The hv_isolation_type_en_snp() in drivers/hv/hv.c and
drivers/hv/hv_common.c can be changed to hv_isolation_type_snp() since
we know !ms_hyperv.paravisor_present is true there.

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Tianyu Lan <tiala@microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/r/20230824080712.30327-10-decui@microsoft.com

diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index c4cffa3..2b01243 100644 (file)
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -52,7 +52,7 @@ static int hyperv_init_ghcb(void)
        void *ghcb_va;
        void **ghcb_base;
 
-       if (!hv_isolation_type_snp())
+       if (!ms_hyperv.paravisor_present || !hv_isolation_type_snp())
                return 0;
 
        if (!hv_ghcb_pg)
@@ -117,7 +117,7 @@ static int hv_cpu_init(unsigned int cpu)
                         * is blocked to run in Confidential VM. So only decrypt assist
                         * page in non-root partition here.
                         */
-                       if (*hvp && hv_isolation_type_en_snp()) {
+                       if (*hvp && !ms_hyperv.paravisor_present && hv_isolation_type_snp()) {
                                WARN_ON_ONCE(set_memory_decrypted((unsigned long)(*hvp), 1));
                                memset(*hvp, 0, PAGE_SIZE);
                        }
@@ -460,7 +460,7 @@ void __init hyperv_init(void)
                        goto common_free;
        }
 
-       if (hv_isolation_type_snp()) {
+       if (ms_hyperv.paravisor_present && hv_isolation_type_snp()) {
                /* Negotiate GHCB Version. */
                if (!hv_ghcb_negotiate_protocol())
                        hv_ghcb_terminate(SEV_TERM_SET_GEN,
@@ -583,7 +583,7 @@ skip_hypercall_pg_init:
        hv_query_ext_cap(0);
 
        /* Find the VTL */
-       if (hv_isolation_type_en_snp())
+       if (!ms_hyperv.paravisor_present && hv_isolation_type_snp())
                ms_hyperv.vtl = get_vtl();
 
        return;

diff --git a/arch/x86/hyperv/ivm.c b/arch/x86/hyperv/ivm.c
index fbc0749..3d48f82 100644 (file)
--- a/arch/x86/hyperv/ivm.c
+++ b/arch/x86/hyperv/ivm.c
@@ -637,7 +637,7 @@ bool hv_is_isolation_supported(void)
 DEFINE_STATIC_KEY_FALSE(isolation_type_snp);
 
 /*
- * hv_isolation_type_snp - Check system runs in the AMD SEV-SNP based
+ * hv_isolation_type_snp - Check if the system runs in an AMD SEV-SNP based
  * isolation VM.
  */
 bool hv_isolation_type_snp(void)
@@ -645,16 +645,6 @@ bool hv_isolation_type_snp(void)
        return static_branch_unlikely(&isolation_type_snp);
 }
 
-DEFINE_STATIC_KEY_FALSE(isolation_type_en_snp);
-/*
- * hv_isolation_type_en_snp - Check system runs in the AMD SEV-SNP based
- * isolation enlightened VM.
- */
-bool hv_isolation_type_en_snp(void)
-{
-       return static_branch_unlikely(&isolation_type_en_snp);
-}
-
 DEFINE_STATIC_KEY_FALSE(isolation_type_tdx);
 /*
  * hv_isolation_type_tdx - Check if the system runs in an Intel TDX based

diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index 101f71b..66ca641 100644 (file)
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -26,7 +26,6 @@
 union hv_ghcb;
 
 DECLARE_STATIC_KEY_FALSE(isolation_type_snp);
-DECLARE_STATIC_KEY_FALSE(isolation_type_en_snp);
 DECLARE_STATIC_KEY_FALSE(isolation_type_tdx);
 
 typedef int (*hyperv_fill_flush_list_func)(
@@ -50,7 +49,7 @@ extern u64 hv_current_partition_id;
 
 extern union hv_ghcb * __percpu *hv_ghcb_pg;
 
-extern bool hv_isolation_type_en_snp(void);
+bool hv_isolation_type_snp(void);
 bool hv_isolation_type_tdx(void);
 u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2);
 
@@ -79,7 +78,7 @@ static inline u64 hv_do_hypercall(u64 control, void *input, void *output)
        if (hv_isolation_type_tdx() && !hyperv_paravisor_present)
                return hv_tdx_hypercall(control, input_address, output_address);
 
-       if (hv_isolation_type_en_snp()) {
+       if (hv_isolation_type_snp() && !hyperv_paravisor_present) {
                __asm__ __volatile__("mov %4, %%r8\n"
                                     "vmmcall"
                                     : "=a" (hv_status), ASM_CALL_CONSTRAINT,
@@ -135,7 +134,7 @@ static inline u64 _hv_do_fast_hypercall8(u64 control, u64 input1)
        if (hv_isolation_type_tdx() && !hyperv_paravisor_present)
                return hv_tdx_hypercall(control, input1, 0);
 
-       if (hv_isolation_type_en_snp()) {
+       if (hv_isolation_type_snp() && !hyperv_paravisor_present) {
                __asm__ __volatile__(
                                "vmmcall"
                                : "=a" (hv_status), ASM_CALL_CONSTRAINT,
@@ -189,7 +188,7 @@ static inline u64 _hv_do_fast_hypercall16(u64 control, u64 input1, u64 input2)
        if (hv_isolation_type_tdx() && !hyperv_paravisor_present)
                return hv_tdx_hypercall(control, input1, input2);
 
-       if (hv_isolation_type_en_snp()) {
+       if (hv_isolation_type_snp() && !hyperv_paravisor_present) {
                __asm__ __volatile__("mov %4, %%r8\n"
                                     "vmmcall"
                                     : "=a" (hv_status), ASM_CALL_CONSTRAINT,
@@ -284,8 +283,6 @@ static inline void hv_ghcb_terminate(unsigned int set, unsigned int reason) {}
 static inline int hv_snp_boot_ap(int cpu, unsigned long start_ip) { return 0; }
 #endif
 
-extern bool hv_isolation_type_snp(void);
-
 #if defined(CONFIG_AMD_MEM_ENCRYPT) || defined(CONFIG_INTEL_TDX_GUEST)
 void hv_vtom_init(void);
 void hv_ivm_msr_write(u64 msr, u64 value);

diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 4f51dac..b63590f 100644 (file)
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -304,7 +304,7 @@ static void __init hv_smp_prepare_cpus(unsigned int max_cpus)
         *  Override wakeup_secondary_cpu_64 callback for SEV-SNP
         *  enlightened guest.
         */
-       if (hv_isolation_type_en_snp()) {
+       if (!ms_hyperv.paravisor_present && hv_isolation_type_snp()) {
                apic->wakeup_secondary_cpu_64 = hv_snp_boot_ap;
                return;
        }
@@ -440,10 +440,7 @@ static void __init ms_hyperv_init_platform(void)
 
 
                if (hv_get_isolation_type() == HV_ISOLATION_TYPE_SNP) {
-                       if (ms_hyperv.paravisor_present)
-                               static_branch_enable(&isolation_type_snp);
-                       else
-                               static_branch_enable(&isolation_type_en_snp);
+                       static_branch_enable(&isolation_type_snp);
                } else if (hv_get_isolation_type() == HV_ISOLATION_TYPE_TDX) {
                        static_branch_enable(&isolation_type_tdx);
 
@@ -556,7 +553,8 @@ 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 || hv_isolation_type_en_snp())
+       if (hv_root_partition ||
+           (!ms_hyperv.paravisor_present && hv_isolation_type_snp()))
                smp_ops.smp_prepare_cpus = hv_smp_prepare_cpus;
 # endif
 

diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index 523c5d9..51e5018 100644 (file)
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -164,7 +164,7 @@ int hv_synic_alloc(void)
                }
 
                if (!ms_hyperv.paravisor_present &&
-                   (hv_isolation_type_en_snp() || hv_isolation_type_tdx())) {
+                   (hv_isolation_type_snp() || hv_isolation_type_tdx())) {
                        ret = set_memory_decrypted((unsigned long)
                                hv_cpu->synic_message_page, 1);
                        if (ret) {
@@ -225,7 +225,7 @@ void hv_synic_free(void)
                }
 
                if (!ms_hyperv.paravisor_present &&
-                   (hv_isolation_type_en_snp() || hv_isolation_type_tdx())) {
+                   (hv_isolation_type_snp() || hv_isolation_type_tdx())) {
                        if (hv_cpu->synic_message_page) {
                                ret = set_memory_encrypted((unsigned long)
                                        hv_cpu->synic_message_page, 1);

diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
index e62d647..81aa8be 100644 (file)
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -383,7 +383,7 @@ int hv_common_cpu_init(unsigned int cpu)
                }
 
                if (!ms_hyperv.paravisor_present &&
-                   (hv_isolation_type_en_snp() || hv_isolation_type_tdx())) {
+                   (hv_isolation_type_snp() || hv_isolation_type_tdx())) {
                        ret = set_memory_decrypted((unsigned long)mem, pgcount);
                        if (ret) {
                                /* It may be unsafe to free 'mem' */
@@ -532,12 +532,6 @@ bool __weak hv_isolation_type_snp(void)
 }
 EXPORT_SYMBOL_GPL(hv_isolation_type_snp);
 
-bool __weak hv_isolation_type_en_snp(void)
-{
-       return false;
-}
-EXPORT_SYMBOL_GPL(hv_isolation_type_en_snp);
-
 bool __weak hv_isolation_type_tdx(void)
 {
        return false;

diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index f577eff..e7ecf03 100644 (file)
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -64,8 +64,7 @@ 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);
+bool hv_isolation_type_snp(void);
 bool hv_isolation_type_tdx(void);
 
 /* Helper functions that provide a consistent pattern for checking Hyper-V hypercall status. */