[RFC Part2 PATCH 10/30] crypto: ccp: shutdown SNP firmware on kexec

[Brijesh Singh]

When the kernel is getting ready to kexec, it calls the device_shutdown() to
allow drivers to cleanup before the kexec. If SEV firmware is initialized
then shut it down before kexec'ing the new kernel.

Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Joerg Roedel <jroedel@xxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxx>
Cc: "Peter Zijlstra (Intel)" <peterz@xxxxxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Sean Christopherson <seanjc@xxxxxxxxxx>
Cc: x86@xxxxxxxxxx
Cc: kvm@xxxxxxxxxxxxxxx
Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>
---
 drivers/crypto/ccp/sev-dev.c | 18 ++++++++++++------
 drivers/crypto/ccp/sp-pci.c  | 12 ++++++++++++
 2 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index c983a8b040c3..562501c43d8f 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -1110,6 +1110,15 @@ int sev_dev_init(struct psp_device *psp)
 	return ret;
 }
 
+static void sev_firmware_shutdown(void)
+{
+	if (boot_cpu_has(X86_FEATURE_SEV))
+		sev_platform_shutdown(NULL);
+
+	if (boot_cpu_has(X86_FEATURE_SEV_SNP))
+		sev_snp_shutdown(NULL);
+}
+
 void sev_dev_destroy(struct psp_device *psp)
 {
 	struct sev_device *sev = psp->sev_data;
@@ -1117,6 +1126,8 @@ void sev_dev_destroy(struct psp_device *psp)
 	if (!sev)
 		return;
 
+	sev_firmware_shutdown();
+
 	if (sev->misc)
 		kref_put(&misc_dev->refcount, sev_exit);
 
@@ -1272,12 +1283,7 @@ void sev_pci_exit(void)
 	if (!psp_master->sev_data)
 		return;
 
-	if (boot_cpu_has(X86_FEATURE_SEV))
-		sev_platform_shutdown(NULL);
-
-	if (boot_cpu_has(X86_FEATURE_SEV_SNP))
-		sev_snp_shutdown(NULL);
-
+	sev_firmware_shutdown();
 
 	if (sev_es_tmr) {
 		/* The TMR area was encrypted, flush it from the cache */
diff --git a/drivers/crypto/ccp/sp-pci.c b/drivers/crypto/ccp/sp-pci.c
index f471dbaef1fb..9210bfda91a2 100644
--- a/drivers/crypto/ccp/sp-pci.c
+++ b/drivers/crypto/ccp/sp-pci.c
@@ -239,6 +239,17 @@ static int sp_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	return ret;
 }
 
+static void sp_pci_shutdown(struct pci_dev *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct sp_device *sp = dev_get_drvdata(dev);
+
+	if (!sp)
+		return;
+
+	sp_destroy(sp);
+}
+
 static void sp_pci_remove(struct pci_dev *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -368,6 +379,7 @@ static struct pci_driver sp_pci_driver = {
 	.id_table = sp_pci_table,
 	.probe = sp_pci_probe,
 	.remove = sp_pci_remove,
+	.shutdown = sp_pci_shutdown,
 	.driver.pm = &sp_pci_pm_ops,
 };
 
-- 
2.17.1