crypto: ccp - Flush the SEV-ES TMR memory before giving it to firmware

[ 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>
This commit is contained in:
Tom Lendacky 2023-01-23 16:53:08 -06:00 committed by Greg Kroah-Hartman
parent 68c1cfd013
commit 457139238f

View File

@ -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");