From: Ashish Kalra <ashish.kalra@xxxxxxx>
To enable ciphertext hiding, it must be specified in the SNP_INIT_EX
command as part of SNP initialization.
Modify the sev_platform_init_args structure, which is used as input to
sev_platform_init(), to include a field that, when non-zero,
indicates that ciphertext hiding should be enabled and specifies the
maximum ASID that can be used for an SEV-SNP guest.
Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
Signed-off-by: Ashish Kalra <ashish.kalra@xxxxxxx>
---
drivers/crypto/ccp/sev-dev.c | 12 +++++++++---
include/linux/psp-sev.h | 10 ++++++++--
2 files changed, 17 insertions(+), 5 deletions(-)
diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index 58c9e040e9ac..334405461657 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -1186,7 +1186,7 @@ static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg)
return 0;
}
-static int __sev_snp_init_locked(int *error)
+static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid)
{
struct psp_device *psp = psp_master;
struct sev_data_snp_init_ex data;
@@ -1247,6 +1247,12 @@ static int __sev_snp_init_locked(int *error)
}
memset(&data, 0, sizeof(data));
+
+ if (max_snp_asid) {
+ data.ciphertext_hiding_en = 1;
+ data.max_snp_asid = max_snp_asid;
+ }
+
data.init_rmp = 1;
data.list_paddr_en = 1;
data.list_paddr = __psp_pa(snp_range_list);
@@ -1433,7 +1439,7 @@ static int _sev_platform_init_locked(struct sev_platform_init_args *args)
if (sev->sev_plat_status.state == SEV_STATE_INIT)
return 0;
- rc = __sev_snp_init_locked(&args->error);
+ rc = __sev_snp_init_locked(&args->error, args->max_snp_asid);
if (rc && rc != -ENODEV)
return rc;
@@ -1516,7 +1522,7 @@ static int snp_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_req
{
int error, rc;
- rc = __sev_snp_init_locked(&error);
+ rc = __sev_snp_init_locked(&error, 0);
if (rc) {
argp->error = SEV_RET_INVALID_PLATFORM_STATE;
return rc;
diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h
index d83185b4268b..e0dbcb4b4fd9 100644
--- a/include/linux/psp-sev.h
+++ b/include/linux/psp-sev.h
@@ -748,10 +748,13 @@ struct sev_data_snp_guest_request {
struct sev_data_snp_init_ex {
u32 init_rmp:1;
u32 list_paddr_en:1;
- u32 rsvd:30;
+ u32 rapl_dis:1;
+ u32 ciphertext_hiding_en:1;
+ u32 rsvd:28;
u32 rsvd1;
u64 list_paddr;
- u8 rsvd2[48];
+ u16 max_snp_asid;
+ u8 rsvd2[46];
} __packed;
/**
@@ -800,10 +803,13 @@ struct sev_data_snp_shutdown_ex {
* @probe: True if this is being called as part of CCP module probe, which
* will defer SEV_INIT/SEV_INIT_EX firmware initialization until needed
* unless psp_init_on_probe module param is set
+ * @max_snp_asid: When non-zero, enable ciphertext hiding and specify the
+ * maximum ASID that can be used for an SEV-SNP guest.
*/
struct sev_platform_init_args {
int error;
bool probe;
+ unsigned int max_snp_asid;
};
/**
--
2.34.1
