From: Tom Lendacky thomas.lendacky@amd.com
[ Upstream commit 46a334a98f585ef78d51d8f5736596887bdd7f54 ]
Perform a cache flush on the SEV-ES TMR memory after allocation to prevent any possibility of the firmware encountering an error should dirty cache lines be present. Use clflush_cache_range() to flush the SEV-ES TMR memory.
Fixes: 97f9ac3db661 ("crypto: ccp - Add support for SEV-ES to the PSP driver") Signed-off-by: Tom Lendacky thomas.lendacky@amd.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/crypto/ccp/sev-dev.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index 7c9149492970d..70174a9118b19 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -24,6 +24,7 @@ #include <linux/cpufeature.h>
#include <asm/smp.h> +#include <asm/cacheflush.h>
#include "psp-dev.h" #include "sev-dev.h" @@ -1114,7 +1115,10 @@ void sev_pci_init(void)
/* Obtain the TMR memory area for SEV-ES use */ sev_es_tmr = sev_fw_alloc(SEV_ES_TMR_SIZE); - if (!sev_es_tmr) + if (sev_es_tmr) + /* Must flush the cache before giving it to the firmware */ + clflush_cache_range(sev_es_tmr, SEV_ES_TMR_SIZE); + else dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n");