[PATCH 6.12.y 2/6] crypto: ccp - Reset TMR size at SNP Shutdown

[Sasha Levin <sashal@kernel.org>]

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

[ Upstream commit 65a895a44e641fe47f3419b064288d1d713024a5 ]

Implicit SNP initialization as part of some SNP ioctls modify TMR size
to be SNP compliant which followed by SNP shutdown will leave the
TMR size modified and then subsequently cause SEV only initialization
to fail, hence, reset TMR size to default at SNP Shutdown.

Acked-by: Dionna Glaze <dionnaglaze@google.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Stable-dep-of: 08f0e65e784c ("crypto: ccp - Do not initialize SNP for ioctl(SNP_CONFIG)")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/crypto/ccp/sev-dev.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index 6f9829448f5db7..0a3ee7e05af2c5 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -1791,6 +1791,9 @@ static int __sev_snp_shutdown_locked(int *error, bool panic)
 	sev->snp_initialized = false;
 	dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n");
 
+	/* Reset TMR size back to default */
+	sev_es_tmr_size = SEV_TMR_SIZE;
+
 	return ret;
 }
 
-- 
2.53.0