[PATCH] x86/sev: mem_encrypt_free_decrypted_mem(): encrypt the pages for AMD SME only

From: Dexuan Cui
Date: Sun Nov 27 2022 - 20:29:25 EST


sme_postprocess_startup() marks the __start_bss_decrypted pages shared
for AMD SME only, so here set_memory_encrypted() should be called for AMD
SME only, i.e. don't call the set_memory_encrypted() for TDX, otherwise the
error "failed to free unused decrypted pages" appears in 'dmesg'.

Fixes: b3f0907c71e0 ("x86/mm: Add .bss..decrypted section to hold shared variables")
Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
---
arch/x86/mm/mem_encrypt_amd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/mm/mem_encrypt_amd.c b/arch/x86/mm/mem_encrypt_amd.c
index 9c4d8dbcb129..fd9b58402a22 100644
--- a/arch/x86/mm/mem_encrypt_amd.c
+++ b/arch/x86/mm/mem_encrypt_amd.c
@@ -516,7 +516,7 @@ void __init mem_encrypt_free_decrypted_mem(void)
* The unused memory range was mapped decrypted, change the encryption
* attribute from decrypted to encrypted before freeing it.
*/
- if (cc_platform_has(CC_ATTR_MEM_ENCRYPT)) {
+ if (sme_me_mask && cc_platform_has(CC_ATTR_MEM_ENCRYPT)) {
r = set_memory_encrypted(vaddr, npages);
if (r) {
pr_warn("failed to free unused decrypted pages\n");
--
2.25.1