From 3d6edc325c52082ab63ffd003c55a4ed875a52c5 Mon Sep 17 00:00:00 2001
From: Andrey Skvortsov <andrej.skvortzov@gmail.com>
Date: Tue, 5 Sep 2023 22:09:25 +0300
Subject: [PATCH] feat(build): check that .text section starts at page boundary

Linker may decide to put new unspecified sections before .text
section. That will cause non-working image, because entry point isn't
at __BLXX_START__. Device just not booted with such image.

This happened for example with .note.gnu.build-id section generated
for LTO build in some cases. Now linker will report this situation as
an error.

```
/usr/lib/gcc-cross/aarch64-linux-gnu/13/../../../../aarch64-linux-gnu/bin/ld: .text is not aligned on a page boundary.
collect2: error: ld returned 1 exit status
```

Signed-off-by: Andrey Skvortsov <andrej.skvortzov@gmail.com>
Change-Id: I5ae46ddd1e6e431e1df1715d1d301f6dd7181cc7
---
 bl1/bl1.ld.S            | 6 ++++++
 bl2/bl2.ld.S            | 6 ++++++
 bl2/bl2_el3.ld.S        | 6 ++++++
 bl2u/bl2u.ld.S          | 6 ++++++
 bl31/bl31.ld.S          | 6 ++++++
 bl32/sp_min/sp_min.ld.S | 6 ++++++
 bl32/tsp/tsp.ld.S       | 6 ++++++
 7 files changed, 42 insertions(+)

diff --git a/bl1/bl1.ld.S b/bl1/bl1.ld.S
index 49dda855e..d25ec63fb 100644
--- a/bl1/bl1.ld.S
+++ b/bl1/bl1.ld.S
@@ -36,6 +36,9 @@ SECTIONS {
 
 #if SEPARATE_CODE_AND_RODATA
     .text . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".text address is not aligned on a page boundary.");
+
         __TEXT_START__ = .;
 
         *bl1_entrypoint.o(.text*)
@@ -80,6 +83,9 @@ SECTIONS {
     } >ROM
 #else /* SEPARATE_CODE_AND_RODATA */
     .ro . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".ro address is not aligned on a page boundary.");
+
         __RO_START__ = .;
 
         *bl1_entrypoint.o(.text*)
diff --git a/bl2/bl2.ld.S b/bl2/bl2.ld.S
index db83a0c50..310e6fe78 100644
--- a/bl2/bl2.ld.S
+++ b/bl2/bl2.ld.S
@@ -25,6 +25,9 @@ SECTIONS {
 
 #if SEPARATE_CODE_AND_RODATA
     .text . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".text address is not aligned on a page boundary.");
+
         __TEXT_START__ = .;
 
 #if ENABLE_RME
@@ -65,6 +68,9 @@ SECTIONS {
     } >RAM
 #else /* SEPARATE_CODE_AND_RODATA */
     .ro . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".ro address is not aligned on a page boundary.");
+
         __RO_START__ = .;
 
         *bl2_entrypoint.o(.text*)
diff --git a/bl2/bl2_el3.ld.S b/bl2/bl2_el3.ld.S
index 4aa5cb045..811f41e14 100644
--- a/bl2/bl2_el3.ld.S
+++ b/bl2/bl2_el3.ld.S
@@ -55,6 +55,9 @@ SECTIONS {
 
 #if SEPARATE_CODE_AND_RODATA
     .text . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".text address is not aligned on a page boundary.");
+
         __TEXT_START__ = .;
         __TEXT_RESIDENT_START__ = .;
 
@@ -89,6 +92,9 @@ SECTIONS {
         "Resident part of BL2 has exceeded its limit.")
 #else /* SEPARATE_CODE_AND_RODATA */
     .ro . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".ro address is not aligned on a page boundary.");
+
         __RO_START__ = .;
         __TEXT_RESIDENT_START__ = .;
 
diff --git a/bl2u/bl2u.ld.S b/bl2u/bl2u.ld.S
index 7b1a10103..ee6a02065 100644
--- a/bl2u/bl2u.ld.S
+++ b/bl2u/bl2u.ld.S
@@ -27,6 +27,9 @@ SECTIONS {
 
 #if SEPARATE_CODE_AND_RODATA
     .text . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".text address is not aligned on a page boundary.");
+
         __TEXT_START__ = .;
 
         *bl2u_entrypoint.o(.text*)
@@ -60,6 +63,9 @@ SECTIONS {
     } >RAM
 #else /* SEPARATE_CODE_AND_RODATA */
     .ro . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".ro address is not aligned on a page boundary.");
+
         __RO_START__ = .;
 
         *bl2u_entrypoint.o(.text*)
diff --git a/bl31/bl31.ld.S b/bl31/bl31.ld.S
index 773b41d3e..8698dffd4 100644
--- a/bl31/bl31.ld.S
+++ b/bl31/bl31.ld.S
@@ -37,6 +37,9 @@ SECTIONS {
 
 #if SEPARATE_CODE_AND_RODATA
     .text . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".text is not aligned on a page boundary.");
+
         __TEXT_START__ = .;
 
         *bl31_entrypoint.o(.text*)
@@ -71,6 +74,9 @@ SECTIONS {
     } >RAM
 #else /* SEPARATE_CODE_AND_RODATA */
     .ro . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".ro is not aligned on a page boundary.");
+
         __RO_START__ = .;
 
         *bl31_entrypoint.o(.text*)
diff --git a/bl32/sp_min/sp_min.ld.S b/bl32/sp_min/sp_min.ld.S
index dd8197332..a2d9b7bf6 100644
--- a/bl32/sp_min/sp_min.ld.S
+++ b/bl32/sp_min/sp_min.ld.S
@@ -29,6 +29,9 @@ SECTIONS {
 
 #if SEPARATE_CODE_AND_RODATA
     .text . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".text address is not aligned on a page boundary.");
+
         __TEXT_START__ = .;
 
         *entrypoint.o(.text*)
@@ -67,6 +70,9 @@ SECTIONS {
     } >RAM
 #else /* SEPARATE_CODE_AND_RODATA */
     .ro . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".ro address is not aligned on a page boundary.");
+
         __RO_START__ = .;
 
         *entrypoint.o(.text*)
diff --git a/bl32/tsp/tsp.ld.S b/bl32/tsp/tsp.ld.S
index 22bf11dad..5116b20ac 100644
--- a/bl32/tsp/tsp.ld.S
+++ b/bl32/tsp/tsp.ld.S
@@ -25,6 +25,9 @@ SECTIONS {
 
 #if SEPARATE_CODE_AND_RODATA
     .text . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".text address is not aligned on a page boundary.");
+
         __TEXT_START__ = .;
 
         *tsp_entrypoint.o(.text*)
@@ -51,6 +54,9 @@ SECTIONS {
     } >RAM
 #else /* SEPARATE_CODE_AND_RODATA */
     .ro . : {
+        ASSERT(. == ALIGN(PAGE_SIZE),
+        ".ro address is not aligned on a page boundary.");
+
         __RO_START__ = .;
 
         *tsp_entrypoint.o(.text*)