[PATCH v2 1/6] percpu: Page-align decrypted data in UP kernels

[Zack Rusin <zack.rusin@broadcom.com>]

Without SMP, DEFINE_PER_CPU_DECRYPTED() places variables in
.data..decrypted. Align both ends of that section so that changing a
variable's encryption attribute cannot expose unrelated kernel data.
Keep the section in permanent data, where UP variables are instantiated.

Fixes: 000f8870a47b ("vmlinux.lds.h: Fix placement of '.data..decrypted' section")
Signed-off-by: Zack Rusin <zack.rusin@broadcom.com>
---
 include/asm-generic/vmlinux.lds.h | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index b2988aa12f66..64bc2bfdd2ec 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -368,10 +368,19 @@
 /*
  * .data section
  */
+#if defined(CONFIG_AMD_MEM_ENCRYPT) && !defined(CONFIG_SMP)
+#define DATA_DECRYPTED							\
+	. = ALIGN(PAGE_SIZE);						\
+	*(.data..decrypted)						\
+	. = ALIGN(PAGE_SIZE);
+#else
+#define DATA_DECRYPTED	*(.data..decrypted)
+#endif
+
 #define DATA_DATA							\
 	*(.xiptext)							\
 	*(DATA_MAIN)							\
-	*(.data..decrypted)						\
+	DATA_DECRYPTED							\
 	*(.ref.data)							\
 	*(.data..shared_aligned) /* percpu related */			\
 	*(.data..unlikely)						\
-- 
2.53.0