[PATCH v5 7/7] crypto: ccp: Move SEV/SNP Platform initialization to KVM

Ashish Kalra
2025-02-25T21:02:22Z

From: Ashish Kalra <ashish.kalra@amd.com>

SNP initialization is forced during PSP driver probe purely because SNP
can't be initialized if VMs are running. But the only in-tree user of
SEV/SNP functionality is KVM, and KVM depends on PSP driver for the same.
Forcing SEV/SNP initialization because a hypervisor could be running
legacy non-confidential VMs make no sense.

This patch removes SEV/SNP initialization from the PSP driver probe
time and moves the requirement to initialize SEV/SNP functionality
to KVM if it wants to use SEV/SNP.

Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Alexey Kardashevskiy <aik@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
---
drivers/crypto/ccp/sev-dev.c | 16 ----------------
1 file changed, 16 deletions(-)

diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index cde6ebab589d..42988d757665 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -1345,10 +1345,6 @@ static int _sev_platform_init_locked(struct sev_platform_init_args *args)
if (sev->state == SEV_STATE_INIT)
return 0;

- /*
- * Legacy guests cannot be running while SNP_INIT(_EX) is executing,
- * so perform SEV-SNP initialization at probe time.
- */
rc = __sev_snp_init_locked(&args->error);
if (rc && rc != -ENODEV) {
/*
@@ -2516,9 +2512,7 @@ EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
void sev_pci_init(void)
{
struct sev_device *sev = psp_master->sev_data;
- struct sev_platform_init_args args = {0};
u8 api_major, api_minor, build;
- int rc;

if (!sev)
return;
@@ -2541,16 +2535,6 @@ void sev_pci_init(void)
api_major, api_minor, build,
sev->api_major, sev->api_minor, sev->build);

- /* Initialize the platform */
- args.probe = true;
- rc = sev_platform_init(&args);
- if (rc)
- dev_err(sev->dev, "SEV: failed to INIT error %#x, rc %d\n",
- args.error, rc);
-
- dev_info(sev->dev, "SEV%s API:%d.%d build:%d\n", sev->snp_initialized ?
- "-SNP" : "", sev->api_major, sev->api_minor, sev->build);
-
return;

err:
--
2.34.1