[PATCH 9/9] x86/hyperv: Remove hv_isolation_type_en_snp

Dexuan Cui
2023-08-11T22:20:28Z

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
!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 !hyperv_paravisor_present is true there.

Signed-off-by: Dexuan Cui <decui@microsoft.com>
---
arch/x86/hyperv/hv_init.c | 2 +-
arch/x86/hyperv/ivm.c | 12 +-----------
arch/x86/kernel/cpu/mshyperv.c | 6 ++----
drivers/hv/hv.c | 4 ++--
drivers/hv/hv_common.c | 8 +-------
5 files changed, 7 insertions(+), 25 deletions(-)

diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index abd0a8bd3f15e..b23466c1cd574 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -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 && !hyperv_paravisor_present && hv_isolation_type_snp()) {
WARN_ON_ONCE(set_memory_decrypted((unsigned long)(*hvp), 1));
memset(*hvp, 0, PAGE_SIZE);
}
diff --git a/arch/x86/hyperv/ivm.c b/arch/x86/hyperv/ivm.c
index b8fb1557c1986..068f05574067c 100644
--- a/arch/x86/hyperv/ivm.c
+++ b/arch/x86/hyperv/ivm.c
@@ -586,7 +586,7 @@ 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)
@@ -594,16 +594,6 @@ 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/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index fb585d3b080b1..6b464ed3cf546 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -306,7 +306,7 @@ 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 (!hyperv_paravisor_present && hv_isolation_type_snp())
apic->wakeup_secondary_cpu_64 = hv_snp_boot_ap;

if (!hv_root_partition)
@@ -442,9 +442,7 @@ static void __init ms_hyperv_init_platform(void)
ms_hyperv.isolation_config_a, ms_hyperv.isolation_config_b);

- if (cc_platform_has(CC_ATTR_GUEST_SEV_SNP)) {
- static_branch_enable(&isolation_type_en_snp);
- } else if (hv_get_isolation_type() == HV_ISOLATION_TYPE_SNP) {
+ if (hv_get_isolation_type() == HV_ISOLATION_TYPE_SNP) {
static_branch_enable(&isolation_type_snp);
} else if (hv_get_isolation_type() == HV_ISOLATION_TYPE_TDX) {
static_branch_enable(&isolation_type_tdx);
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index 6b5f1805d4749..932b8bc239acb 100644
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -166,7 +166,7 @@ int hv_synic_alloc(void)
}

if (!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) {
@@ -227,7 +227,7 @@ void hv_synic_free(void)
}

if (!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 c0b0ac44ffa3c..d3f95a1be1e99 100644
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -386,7 +386,7 @@ int hv_common_cpu_init(unsigned int cpu)
}

if (!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' */
@@ -535,12 +535,6 @@ 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;
--
2.25.1