[PATCH 1/5] x86/sme: Clear decrypted BSS separately

[Brian Gerst]

The decrypted BSS section needs to be cleared after it is remapped as
decrypted memory.  Separate it so that the normal BSS section can be
cleared earlier.

Signed-off-by: Brian Gerst <brgerst@xxxxxxxxx>
---
 arch/x86/kernel/vmlinux.lds.S | 2 +-
 arch/x86/mm/mem_encrypt_amd.c | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 2438b89a4620..e64c797e06c7 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -365,9 +365,9 @@ SECTIONS
 		*(.bss..page_aligned)
 		. = ALIGN(PAGE_SIZE);
 		*(BSS_MAIN)
-		BSS_DECRYPTED
 		. = ALIGN(PAGE_SIZE);
 		__bss_stop = .;
+		BSS_DECRYPTED
 	}
 
 	/*
diff --git a/arch/x86/mm/mem_encrypt_amd.c b/arch/x86/mm/mem_encrypt_amd.c
index 2f8c32173972..d39e1e29bcb9 100644
--- a/arch/x86/mm/mem_encrypt_amd.c
+++ b/arch/x86/mm/mem_encrypt_amd.c
@@ -479,6 +479,9 @@ void __init sme_early_init(void)
 	if (!sme_me_mask)
 		return;
 
+	memset(__start_bss_decrypted, 0,
+	       (unsigned long) __end_bss_decrypted - (unsigned long) __start_bss_decrypted);
+
 	early_pmd_flags = __sme_set(early_pmd_flags);
 
 	__supported_pte_mask = __sme_set(__supported_pte_mask);
-- 
2.55.0