Re: [PATCH v2 16/25] crypto: ccp: Handle the legacy TMR allocation when SNP is enabled

Borislav Petkov
2024-01-29T15:05:15Z

On Thu, Jan 25, 2024 at 10:11:16PM -0600, Michael Roth wrote:
> @@ -641,14 +774,16 @@ static int __sev_platform_init_locked(int *error)

That function - especially when looking at the next patch - becomes too
big and hard to follow.

Let's add subfunctions for each thing, diff ontop:

---
diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index fa992ce57ffe..70aabd1d3d5f 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -759,6 +759,22 @@ static int __sev_snp_init_locked(int *error)
return rc;
}

+static void __sev_platform_init_handle_tmr(struct sev_device *sev)
+{
+ if (sev_es_tmr)
+ return;
+
+ /* Obtain the TMR memory area for SEV-ES use */
+ sev_es_tmr = sev_fw_alloc(sev_es_tmr_size);
+ if (sev_es_tmr) {
+ /* Must flush the cache before giving it to the firmware */
+ if (!sev->snp_initialized)
+ clflush_cache_range(sev_es_tmr, sev_es_tmr_size);
+ } else {
+ dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n");
+ }
+}
+
static int __sev_platform_init_locked(int *error)
{
int rc, psp_ret = SEV_RET_NO_FW_CALL;
@@ -772,18 +788,7 @@ static int __sev_platform_init_locked(int *error)
if (sev->state == SEV_STATE_INIT)
return 0;

- if (!sev_es_tmr) {
- /* Obtain the TMR memory area for SEV-ES use */
- sev_es_tmr = sev_fw_alloc(sev_es_tmr_size);
- if (sev_es_tmr) {
- /* Must flush the cache before giving it to the firmware */
- if (!sev->snp_initialized)
- clflush_cache_range(sev_es_tmr, sev_es_tmr_size);
- } else {
- dev_warn(sev->dev,
- "SEV: TMR allocation failed, SEV-ES support unavailable\n");
- }
- }
+ __sev_platform_init_handle_tmr(sev);

if (sev_init_ex_buffer) {
rc = sev_read_init_ex_file();

--
Regards/Gruss,
Boris.