From: Tom Lendacky <[email protected]>
Performing a WBINVD and DF_FLUSH are expensive operations. The SEV support
currently performs this WBINVD/DF_FLUSH combination when an SEV guest is
terminated, so there is no need for it to be done before LAUNCH.
However, when the SEV firmware transitions the platform from UNINIT state
to INIT state, all ASIDs will be marked invalid across all threads.
Therefore, as part of transitioning the platform to INIT state, perform a
WBINVD/DF_FLUSH after a successful INIT in the PSP/SEV device driver.
Since the PSP/SEV device driver is x86 only, it can reference and use the
WBINVD related functions directly.
Cc: Gary Hook <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: "David S. Miller" <[email protected]>
Tested-by: David Rientjes <[email protected]>
Signed-off-by: Tom Lendacky <[email protected]>
---
arch/x86/kvm/svm.c | 15 ---------------
drivers/crypto/ccp/psp-dev.c | 9 +++++++++
2 files changed, 9 insertions(+), 15 deletions(-)
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 1d217680cf83..389dfd7594eb 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -6329,21 +6329,6 @@ static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error)
int asid = sev_get_asid(kvm);
int ret;
- /*
- * Guard against a DEACTIVATE command before the DF_FLUSH command
- * has completed.
- */
- mutex_lock(&sev_deactivate_lock);
-
- wbinvd_on_all_cpus();
-
- ret = sev_guest_df_flush(error);
-
- mutex_unlock(&sev_deactivate_lock);
-
- if (ret)
- return ret;
-
data = kzalloc(sizeof(*data), GFP_KERNEL_ACCOUNT);
if (!data)
return -ENOMEM;
diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
index 6b17d179ef8a..39fdd0641637 100644
--- a/drivers/crypto/ccp/psp-dev.c
+++ b/drivers/crypto/ccp/psp-dev.c
@@ -21,6 +21,8 @@
#include <linux/ccp.h>
#include <linux/firmware.h>
+#include <asm/smp.h>
+
#include "sp-dev.h"
#include "psp-dev.h"
@@ -235,6 +237,13 @@ static int __sev_platform_init_locked(int *error)
return rc;
psp->sev_state = SEV_STATE_INIT;
+
+ /* Prepare for first SEV guest launch after INIT */
+ wbinvd_on_all_cpus();
+ rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error);
+ if (rc)
+ return rc;
+
dev_dbg(psp->dev, "SEV firmware initialized\n");
return rc;
--
2.17.1