From 84a6c487e494a9408bc4d6a34145ee2f22292808 Mon Sep 17 00:00:00 2001
From: Clement Dieperink <clement.dieperink@heig-vd.ch>
Date: Wed, 3 Dec 2025 14:28:19 +0100
Subject: [PATCH 01/17] fixes to correct bug introduced by the MUSL support

---
 so3/arch/arm64/traps.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/so3/arch/arm64/traps.c b/so3/arch/arm64/traps.c
index d154731e8..a4cd707af 100644
--- a/so3/arch/arm64/traps.c
+++ b/so3/arch/arm64/traps.c
@@ -252,7 +252,7 @@ void trap_handle(cpu_regs_t *regs)
 	default:
 __err:
 		lprintk("### On CPU %d: ESR_Elx_EC(esr): 0x%lx\n", smp_processor_id(), ESR_ELx_EC(esr));
-		trap_handle_error(regs->lr);
+		trap_handle_error(regs->pc);
 		kernel_panic();
 	}
 }

From 4e6e2172ad72881d9e9314c962970b5457ae3abf Mon Sep 17 00:00:00 2001
From: Clement Dieperink <clement.dieperink@heig-vd.ch>
Date: Wed, 17 Dec 2025 15:30:45 +0100
Subject: [PATCH 02/17] fix for userspace threads

---
 so3/arch/arm64/traps.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/so3/arch/arm64/traps.c b/so3/arch/arm64/traps.c
index a4cd707af..d154731e8 100644
--- a/so3/arch/arm64/traps.c
+++ b/so3/arch/arm64/traps.c
@@ -252,7 +252,7 @@ void trap_handle(cpu_regs_t *regs)
 	default:
 __err:
 		lprintk("### On CPU %d: ESR_Elx_EC(esr): 0x%lx\n", smp_processor_id(), ESR_ELx_EC(esr));
-		trap_handle_error(regs->pc);
+		trap_handle_error(regs->lr);
 		kernel_panic();
 	}
 }

From bec7bbdd880923ddfb959b843186e9eb8df4f47e Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Wed, 10 Dec 2025 18:03:52 +0100
Subject: [PATCH 03/17] [c++] Add basic C++ apps

The apps are: hello-world, simple class & use of std::vector

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 usr/CMakeLists.txt            |  2 +-
 usr/src/tests/CMakeLists.txt  |  5 ++++
 usr/src/tests/class_test.cpp  | 48 +++++++++++++++++++++++++++++++++++
 usr/src/tests/hello_world.cpp | 27 ++++++++++++++++++++
 usr/src/tests/vector_test.cpp | 36 ++++++++++++++++++++++++++
 5 files changed, 117 insertions(+), 1 deletion(-)
 create mode 100644 usr/src/tests/CMakeLists.txt
 create mode 100644 usr/src/tests/class_test.cpp
 create mode 100644 usr/src/tests/hello_world.cpp
 create mode 100644 usr/src/tests/vector_test.cpp

diff --git a/usr/CMakeLists.txt b/usr/CMakeLists.txt
index 387abe07c..f30cd284f 100644
--- a/usr/CMakeLists.txt
+++ b/usr/CMakeLists.txt
@@ -4,7 +4,7 @@
 
 cmake_minimum_required(VERSION 3.16)
 
-project(so3-usr LANGUAGES C ASM)
+project(so3-usr LANGUAGES C CXX ASM)
 
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
diff --git a/usr/src/tests/CMakeLists.txt b/usr/src/tests/CMakeLists.txt
new file mode 100644
index 000000000..63e4efad7
--- /dev/null
+++ b/usr/src/tests/CMakeLists.txt
@@ -0,0 +1,5 @@
+cmake_minimum_required(VERSION 3.16)
+
+add_executable(hello-world.elf hello_world.cpp)
+add_executable(class-test.elf class_test.cpp)
+add_executable(vector-test.elf vector_test.cpp)
diff --git a/usr/src/tests/class_test.cpp b/usr/src/tests/class_test.cpp
new file mode 100644
index 000000000..b01eb3864
--- /dev/null
+++ b/usr/src/tests/class_test.cpp
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2025 Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#include <iostream>
+#include <string>
+
+class Person {
+private:
+    std::string _name;
+    int _age;
+
+public:
+    // Constructor
+    Person(const std::string& name, int age)
+        : _name(name), _age(age) {}
+
+    // Method to print info
+    void hello() const {
+        // std::cout << "Hi, I'm " << _name
+        //           << " and I'm " << _age
+        //           << " years old." << std::endl;
+
+        printf("Hi, I'm %s and I'm %d years old.\n");
+    }
+};
+
+int main()
+{
+    Person p("Jean-Pierre", 30);
+    p.hello();
+
+    return 0;
+}
diff --git a/usr/src/tests/hello_world.cpp b/usr/src/tests/hello_world.cpp
new file mode 100644
index 000000000..b4a87e6c8
--- /dev/null
+++ b/usr/src/tests/hello_world.cpp
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2025 Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#include <iostream>
+
+int main()
+{
+    // printf("JMI\n");
+    std::cout << "Hello World!" << std::endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/usr/src/tests/vector_test.cpp b/usr/src/tests/vector_test.cpp
new file mode 100644
index 000000000..0f429b362
--- /dev/null
+++ b/usr/src/tests/vector_test.cpp
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2025 Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#include <iostream>
+#include <vector>
+
+int main() {
+    // Create and initialize a vector with 3 integer values
+    std::vector<int> numbers = {10, 20, 30};
+
+    // Compute the sum
+    int sum = 0;
+    for (int value : numbers) {
+        sum += value;
+    }
+
+    // Output the result
+    printf("Sum of vector entries: %d\n", sum);
+
+    return 0;
+}
\ No newline at end of file

From 52c77e109e00cb7db1db42420ff543d0e197e378 Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Wed, 10 Dec 2025 18:05:23 +0100
Subject: [PATCH 04/17] [c++] udpate of CMakeList of usr/scr to compile test
 c++ apps

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 usr/src/CMakeLists.txt | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/usr/src/CMakeLists.txt b/usr/src/CMakeLists.txt
index 8da5d119b..35ebfcf6a 100644
--- a/usr/src/CMakeLists.txt
+++ b/usr/src/CMakeLists.txt
@@ -22,3 +22,8 @@ if (MICROPYTHON AND (${CMAKE_SYSTEM_PROCESSOR} STREQUAL "aarch64"))
 	add_subdirectory(micropython)
 endif()
 
+option(WITH_TESTS "Build the test/example apps" ON)
+if (WITH_TESTS)
+    add_subdirectory(tests)
+endif()
+

From a01803186492a3ff6863cfa9d846ae83b7ae0ce6 Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Wed, 10 Dec 2025 18:06:33 +0100
Subject: [PATCH 05/17] [c++] Add section used by C++ apps to so3

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 so3/kernel/main.c    | 2 +-
 so3/kernel/process.c | 7 ++++---
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/so3/kernel/main.c b/so3/kernel/main.c
index 8858c2447..1bf429d99 100644
--- a/so3/kernel/main.c
+++ b/so3/kernel/main.c
@@ -98,7 +98,7 @@ void kernel_start(void)
 {
 	lprintk("%s", SO3_BANNER);
 
-	LOG_INFO("Now bootstraping the kernel ...");
+	LOG_INFO("Now bootstraping the kernel ...\n");
 
 	/* Memory manager subsystem initialization */
 	memory_init();
diff --git a/so3/kernel/process.c b/so3/kernel/process.c
index 4c9f0ac05..e7c5e21e4 100644
--- a/so3/kernel/process.c
+++ b/so3/kernel/process.c
@@ -74,10 +74,11 @@ static uint32_t pid_current = 1;
 static pcb_t *root_process = NULL; /* root process */
 
 /* only the following sections are supported */
-#define SUPPORTED_SECTION_COUNT 10
-static const char *supported_section_names[SUPPORTED_SECTION_COUNT] = {
-	".init", ".text", ".rodata", ".data", ".sbss", ".bss", ".scommon", ".fini", ".init_array", ".fini_array",
+static const char *supported_section_names[] = {
+	".init", ".text", ".rodata", ".data", ".sbss", ".bss", ".scommon", ".fini",
+	 ".eh_frame", ".gcc_except_table", ".init_array", ".fini_array", ".data.rel.ro", ".got", ".got.plt",
 };
+#define SUPPORTED_SECTION_COUNT (sizeof(supported_section_names) / sizeof(supported_section_names[0]))
 
 /*
  * Find a process (pcb_t) from its pid.

From 7e001eaf5345aca9e21532cc4da47f8996a6bb68 Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Thu, 11 Dec 2025 15:47:27 +0100
Subject: [PATCH 06/17] [c++] Add 'no-rtti' flag in the musl toolchains

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 usr/aarch64-linux-musl.cmake | 2 +-
 usr/arm-linux-musl.cmake     | 3 +--
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/usr/aarch64-linux-musl.cmake b/usr/aarch64-linux-musl.cmake
index a36f89037..f7c353062 100644
--- a/usr/aarch64-linux-musl.cmake
+++ b/usr/aarch64-linux-musl.cmake
@@ -26,4 +26,4 @@ set(CMAKE_ASM_FLAGS "-D__ARM64__ -D__ASSEMBLY__")
 
 set(CMAKE_LINKER "aarch64-linux-musl-ld")
 
-set(CMAKE_EXE_LINKER_FLAGS "-Os -static" CACHE STRING "SO3 usr LDFLAGS for executables")
+set(CMAKE_EXE_LINKER_FLAGS "-Os -static -fno-rtti" CACHE STRING "SO3 usr LDFLAGS for executables")
diff --git a/usr/arm-linux-musl.cmake b/usr/arm-linux-musl.cmake
index 4d38558df..f148c3542 100644
--- a/usr/arm-linux-musl.cmake
+++ b/usr/arm-linux-musl.cmake
@@ -26,5 +26,4 @@ set(CMAKE_ASM_FLAGS "-D__ARM__ -D__ASSEMBLY__")
 
 set(CMAKE_LINKER "arm-linux-musleabihf-ld")
 
-
-set(CMAKE_EXE_LINKER_FLAGS "-Os -static" CACHE STRING "SO3 usr LDFLAGS for executables")
+set(CMAKE_EXE_LINKER_FLAGS "-Os -static -fno-rtti" CACHE STRING "SO3 usr LDFLAGS for executables")

From 7582d0f0ff3d55fe2be582e6644e9f85ee158326 Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Thu, 11 Dec 2025 15:48:23 +0100
Subject: [PATCH 07/17] [usr] Move the '.debug_*' sections in a separated file

The '.debug_*' sections of the usr apps are move in a seperated
file ('app.elf.debug'). The apps is then much lighter. For
example, C++ hello-world shrink form 8.2MB to 884K.

For debug, the app.elf.debug is linked with the app.elf.

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 usr/build.sh  | 30 ++++++++++++++++++++++++++++++
 usr/deploy.sh |  2 +-
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/usr/build.sh b/usr/build.sh
index 747697471..d596d04dc 100755
--- a/usr/build.sh
+++ b/usr/build.sh
@@ -11,6 +11,33 @@ usage() {
   echo "  -h        Print this help"
 }
 
+# Place the debug info of the applications in a separate file
+strip_debug_info()
+{
+  # retrieve the correct objcop tool
+  # if [ "$1" == "virt32" -o "$1" == "rpi4" ]; then
+  if [ "$1" = "virt32" ] || [ "$1" = "rpi4" ]; then
+    OBJCOPY="arm-linux-musleabihf-objcopy"
+  else
+    OBJCOPY="aarch64-linux-musl-objcopy"
+  fi
+
+  for app in build/deploy/*.elf; do
+    [ -e "$app" ] || continue
+
+    # 1. Create a file with only '.debug_*' sections
+    $OBJCOPY --only-keep-debug $app $app.debug
+
+    # 2. remove/strip debug info
+    $OBJCOPY --strip-all $app
+
+    # 3. Connect the two files
+    $OBJCOPY --add-gnu-debuglink=$app.debug $app
+
+  done
+}
+
+
 install_file_elf() {
   if [ -f $1 ] ; then 
     for subfolder_app in $(find build/src -type f -iname "*.elf"); do
@@ -120,4 +147,7 @@ install_directory_root out
 
 install_file_elf
 
+strip_debug_info "$PLATFORM"
+
+
 exit 0
diff --git a/usr/deploy.sh b/usr/deploy.sh
index 8ab92c9b5..c3c2bffd0 100755
--- a/usr/deploy.sh
+++ b/usr/deploy.sh
@@ -18,6 +18,6 @@ echo Deploying user apps into the ramfs partition
 cd ../rootfs
 ./mount.sh  ${PLATFORM}
 sudo cp -r ../usr/out/* fs
-sudo cp -r ../usr/build/deploy/* fs
+sudo cp -r ../usr/build/deploy/*.elf fs
 ./umount.sh  ${PLATFORM}
 

From 98b39a20187986b015e4e5e15266f479adf5a3e2 Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Tue, 16 Dec 2025 10:56:34 +0100
Subject: [PATCH 08/17] [c++] Add some more basic tests

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 usr/src/tests/CMakeLists.txt                  |  4 ++-
 usr/src/tests/allocation_test.cpp             | 34 +++++++++++++++++++
 usr/src/tests/class_test.cpp                  | 15 ++++----
 usr/src/tests/exception_test.cpp              | 28 +++++++++++++++
 usr/src/tests/hello_world.cpp                 |  1 -
 .../{vector_test.cpp => stdlib_test.cpp}      | 33 ++++++++++++++++--
 6 files changed, 104 insertions(+), 11 deletions(-)
 create mode 100644 usr/src/tests/allocation_test.cpp
 create mode 100644 usr/src/tests/exception_test.cpp
 rename usr/src/tests/{vector_test.cpp => stdlib_test.cpp} (72%)

diff --git a/usr/src/tests/CMakeLists.txt b/usr/src/tests/CMakeLists.txt
index 63e4efad7..95e4e692f 100644
--- a/usr/src/tests/CMakeLists.txt
+++ b/usr/src/tests/CMakeLists.txt
@@ -2,4 +2,6 @@ cmake_minimum_required(VERSION 3.16)
 
 add_executable(hello-world.elf hello_world.cpp)
 add_executable(class-test.elf class_test.cpp)
-add_executable(vector-test.elf vector_test.cpp)
+add_executable(stdlib-test.elf stdlib_test.cpp)
+add_executable(exception-test.elf exception_test.cpp)
+add_executable(allocation-test.elf allocation_test.cpp)
diff --git a/usr/src/tests/allocation_test.cpp b/usr/src/tests/allocation_test.cpp
new file mode 100644
index 000000000..9113b0c56
--- /dev/null
+++ b/usr/src/tests/allocation_test.cpp
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2025 Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#include <new>
+#include <iostream>
+
+struct Aligned { alignas(64) int x; };
+
+int main()
+{
+    void* p = ::operator new(1024);
+    ::operator delete(p);
+
+    Aligned* a = new Aligned;
+    delete a;
+
+    std::cout << "Test OK" << std::endl;
+}
+
diff --git a/usr/src/tests/class_test.cpp b/usr/src/tests/class_test.cpp
index b01eb3864..af1d43ec9 100644
--- a/usr/src/tests/class_test.cpp
+++ b/usr/src/tests/class_test.cpp
@@ -25,17 +25,18 @@ class Person {
     int _age;
 
 public:
-    // Constructor
     Person(const std::string& name, int age)
-        : _name(name), _age(age) {}
+        : _name(name), _age(age) {
+            std::cout << "Person constructor" << std::endl;
+    }
+
+    ~Person() {
+            std::cout << "Person Destructor" << std::endl;
+    }
 
     // Method to print info
     void hello() const {
-        // std::cout << "Hi, I'm " << _name
-        //           << " and I'm " << _age
-        //           << " years old." << std::endl;
-
-        printf("Hi, I'm %s and I'm %d years old.\n");
+        std::cout << "Hi, I'm " << _name << " and I'm " << _age << " years old." << std::endl;
     }
 };
 
diff --git a/usr/src/tests/exception_test.cpp b/usr/src/tests/exception_test.cpp
new file mode 100644
index 000000000..8945b01c2
--- /dev/null
+++ b/usr/src/tests/exception_test.cpp
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2025 Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#include <iostream>
+
+int main()
+{
+	try {
+		throw 42;
+    } catch (int x) {
+        std::cout << "caught: " << x << std::endl;
+    }
+}
diff --git a/usr/src/tests/hello_world.cpp b/usr/src/tests/hello_world.cpp
index b4a87e6c8..c37c206be 100644
--- a/usr/src/tests/hello_world.cpp
+++ b/usr/src/tests/hello_world.cpp
@@ -20,7 +20,6 @@
 
 int main()
 {
-    // printf("JMI\n");
     std::cout << "Hello World!" << std::endl;
 
     return 0;
diff --git a/usr/src/tests/vector_test.cpp b/usr/src/tests/stdlib_test.cpp
similarity index 72%
rename from usr/src/tests/vector_test.cpp
rename to usr/src/tests/stdlib_test.cpp
index 0f429b362..1926217ec 100644
--- a/usr/src/tests/vector_test.cpp
+++ b/usr/src/tests/stdlib_test.cpp
@@ -18,8 +18,10 @@
 
 #include <iostream>
 #include <vector>
+#include <map>
 
-int main() {
+void vector_test()
+{
     // Create and initialize a vector with 3 integer values
     std::vector<int> numbers = {10, 20, 30};
 
@@ -30,7 +32,34 @@ int main() {
     }
 
     // Output the result
-    printf("Sum of vector entries: %d\n", sum);
+    std::cout << "Sum of vector entries: " << sum << std::endl;
+}
+
+
+void string_test()
+{
+    std::string s = "abc";
+    s += "def";
+    std::cout << "String: " << s << std::endl;
+}
+
+void map_test()
+{
+    std::map<int,int> m;
+
+    m[1] = 2;
+
+    std::cout << "Map m[1]: " << m[1] << std::endl;
+}
+
+
+int main() {
+
+    vector_test();
+
+    string_test();
+
+    map_test();
 
     return 0;
 }
\ No newline at end of file

From 3ead3c4bab5b1ded88cb9da9d382a5545bdfcbe9 Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Tue, 16 Dec 2025 11:13:09 +0100
Subject: [PATCH 09/17] [c++] Fix clang-format

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 usr/src/tests/allocation_test.cpp | 15 ++++++-----
 usr/src/tests/class_test.cpp      | 40 +++++++++++++++-------------
 usr/src/tests/exception_test.cpp  |  6 ++---
 usr/src/tests/hello_world.cpp     |  4 +--
 usr/src/tests/stdlib_test.cpp     | 44 +++++++++++++++----------------
 5 files changed, 56 insertions(+), 53 deletions(-)

diff --git a/usr/src/tests/allocation_test.cpp b/usr/src/tests/allocation_test.cpp
index 9113b0c56..dca56f86a 100644
--- a/usr/src/tests/allocation_test.cpp
+++ b/usr/src/tests/allocation_test.cpp
@@ -19,16 +19,17 @@
 #include <new>
 #include <iostream>
 
-struct Aligned { alignas(64) int x; };
+struct Aligned {
+	alignas(64) int x;
+};
 
 int main()
 {
-    void* p = ::operator new(1024);
-    ::operator delete(p);
+	void *p = ::operator new(1024);
+	::operator delete(p);
 
-    Aligned* a = new Aligned;
-    delete a;
+	Aligned *a = new Aligned;
+	delete a;
 
-    std::cout << "Test OK" << std::endl;
+	std::cout << "Test OK" << std::endl;
 }
-
diff --git a/usr/src/tests/class_test.cpp b/usr/src/tests/class_test.cpp
index af1d43ec9..eef30af66 100644
--- a/usr/src/tests/class_test.cpp
+++ b/usr/src/tests/class_test.cpp
@@ -20,30 +20,34 @@
 #include <string>
 
 class Person {
-private:
-    std::string _name;
-    int _age;
+    private:
+	std::string _name;
+	int _age;
 
-public:
-    Person(const std::string& name, int age)
-        : _name(name), _age(age) {
-            std::cout << "Person constructor" << std::endl;
-    }
+    public:
+	Person(const std::string &name, int age)
+		: _name(name)
+		, _age(age)
+	{
+		std::cout << "Person constructor" << std::endl;
+	}
 
-    ~Person() {
-            std::cout << "Person Destructor" << std::endl;
-    }
+	~Person()
+	{
+		std::cout << "Person Destructor" << std::endl;
+	}
 
-    // Method to print info
-    void hello() const {
-        std::cout << "Hi, I'm " << _name << " and I'm " << _age << " years old." << std::endl;
-    }
+	// Method to print info
+	void hello() const
+	{
+		std::cout << "Hi, I'm " << _name << " and I'm " << _age << " years old." << std::endl;
+	}
 };
 
 int main()
 {
-    Person p("Jean-Pierre", 30);
-    p.hello();
+	Person p("Jean-Pierre", 30);
+	p.hello();
 
-    return 0;
+	return 0;
 }
diff --git a/usr/src/tests/exception_test.cpp b/usr/src/tests/exception_test.cpp
index 8945b01c2..6026dea25 100644
--- a/usr/src/tests/exception_test.cpp
+++ b/usr/src/tests/exception_test.cpp
@@ -22,7 +22,7 @@ int main()
 {
 	try {
 		throw 42;
-    } catch (int x) {
-        std::cout << "caught: " << x << std::endl;
-    }
+	} catch (int x) {
+		std::cout << "caught: " << x << std::endl;
+	}
 }
diff --git a/usr/src/tests/hello_world.cpp b/usr/src/tests/hello_world.cpp
index c37c206be..4ef192cd0 100644
--- a/usr/src/tests/hello_world.cpp
+++ b/usr/src/tests/hello_world.cpp
@@ -20,7 +20,7 @@
 
 int main()
 {
-    std::cout << "Hello World!" << std::endl;
+	std::cout << "Hello World!" << std::endl;
 
-    return 0;
+	return 0;
 }
\ No newline at end of file
diff --git a/usr/src/tests/stdlib_test.cpp b/usr/src/tests/stdlib_test.cpp
index 1926217ec..a450971be 100644
--- a/usr/src/tests/stdlib_test.cpp
+++ b/usr/src/tests/stdlib_test.cpp
@@ -22,44 +22,42 @@
 
 void vector_test()
 {
-    // Create and initialize a vector with 3 integer values
-    std::vector<int> numbers = {10, 20, 30};
+	// Create and initialize a vector with 3 integer values
+	std::vector<int> numbers = { 10, 20, 30 };
 
-    // Compute the sum
-    int sum = 0;
-    for (int value : numbers) {
-        sum += value;
-    }
+	// Compute the sum
+	int sum = 0;
+	for (int value : numbers) {
+		sum += value;
+	}
 
-    // Output the result
-    std::cout << "Sum of vector entries: " << sum << std::endl;
+	// Output the result
+	std::cout << "Sum of vector entries: " << sum << std::endl;
 }
 
-
 void string_test()
 {
-    std::string s = "abc";
-    s += "def";
-    std::cout << "String: " << s << std::endl;
+	std::string s = "abc";
+	s += "def";
+	std::cout << "String: " << s << std::endl;
 }
 
 void map_test()
 {
-    std::map<int,int> m;
+	std::map<int, int> m;
 
-    m[1] = 2;
+	m[1] = 2;
 
-    std::cout << "Map m[1]: " << m[1] << std::endl;
+	std::cout << "Map m[1]: " << m[1] << std::endl;
 }
 
+int main()
+{
+	vector_test();
 
-int main() {
-
-    vector_test();
-
-    string_test();
+	string_test();
 
-    map_test();
+	map_test();
 
-    return 0;
+	return 0;
 }
\ No newline at end of file

From 049c5f197586adc71ed3b124825ec6a42e495d4e Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Tue, 16 Dec 2025 11:18:58 +0100
Subject: [PATCH 10/17] [c++] clang-format / again

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 so3/kernel/process.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/so3/kernel/process.c b/so3/kernel/process.c
index e7c5e21e4..ccc61a5f4 100644
--- a/so3/kernel/process.c
+++ b/so3/kernel/process.c
@@ -75,8 +75,9 @@ static pcb_t *root_process = NULL; /* root process */
 
 /* only the following sections are supported */
 static const char *supported_section_names[] = {
-	".init", ".text", ".rodata", ".data", ".sbss", ".bss", ".scommon", ".fini",
-	 ".eh_frame", ".gcc_except_table", ".init_array", ".fini_array", ".data.rel.ro", ".got", ".got.plt",
+	".init",       ".text",	      ".rodata",      ".data",	   ".sbss",
+	".bss",	       ".scommon",    ".fini",	      ".eh_frame", ".gcc_except_table",
+	".init_array", ".fini_array", ".data.rel.ro", ".got",	   ".got.plt",
 };
 #define SUPPORTED_SECTION_COUNT (sizeof(supported_section_names) / sizeof(supported_section_names[0]))
 

From 92c056efc59eb09e8233ea31fac8c191c74c5110 Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Mon, 5 Jan 2026 14:37:07 +0100
Subject: [PATCH 11/17] [C++] Add std::thread & std::ofstream (files) tests

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 usr/src/tests/CMakeLists.txt   |  4 ++
 usr/src/tests/files_test.cpp   | 17 +++++++
 usr/src/tests/threads_test.cpp | 88 ++++++++++++++++++++++++++++++++++
 3 files changed, 109 insertions(+)
 create mode 100644 usr/src/tests/files_test.cpp
 create mode 100644 usr/src/tests/threads_test.cpp

diff --git a/usr/src/tests/CMakeLists.txt b/usr/src/tests/CMakeLists.txt
index 95e4e692f..7ae48e239 100644
--- a/usr/src/tests/CMakeLists.txt
+++ b/usr/src/tests/CMakeLists.txt
@@ -5,3 +5,7 @@ add_executable(class-test.elf class_test.cpp)
 add_executable(stdlib-test.elf stdlib_test.cpp)
 add_executable(exception-test.elf exception_test.cpp)
 add_executable(allocation-test.elf allocation_test.cpp)
+add_executable(threads-test.elf threads_test.cpp)
+add_executable(files-test.elf files_test.cpp)
+
+
diff --git a/usr/src/tests/files_test.cpp b/usr/src/tests/files_test.cpp
new file mode 100644
index 000000000..f5316b2db
--- /dev/null
+++ b/usr/src/tests/files_test.cpp
@@ -0,0 +1,17 @@
+
+
+
+#include <fstream>
+#include <iostream>
+
+int main() {
+    std::ofstream file("example.txt");
+    if (!file) {
+        std::cerr << "Failed to open file\n";
+        return 1;
+    }
+
+    file << "Hello from C++\n";
+    // file closes automatically (RAII)
+    return 0;
+}
\ No newline at end of file
diff --git a/usr/src/tests/threads_test.cpp b/usr/src/tests/threads_test.cpp
new file mode 100644
index 000000000..5503c1e0e
--- /dev/null
+++ b/usr/src/tests/threads_test.cpp
@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2025 Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <iostream>
+#include <thread>
+#include <mutex>
+#include <chrono>
+#include <vector>
+
+#include <unistd.h>
+
+struct ThreadArgs {
+    long thread_id;
+    std::mutex* mtx;
+};
+
+// Thread function
+long simple_thread(ThreadArgs args)
+{
+    std::cout << "Thread " << args.thread_id << ": Executing" << std::endl;
+
+    // Lock the mutex
+    args.mtx->lock();
+    std::cout << "Thread " << args.thread_id << ": Locked mutex" << std::endl;
+
+    std::this_thread::sleep_for(std::chrono::seconds(3));
+
+    std::cout << "Thread " << args.thread_id << ": Unlocking mutex" << std::endl;
+    args.mtx->unlock();
+
+    std::cout << "Thread " << args.thread_id << ": Thread finished" << std::endl;
+
+    return args.thread_id;
+}
+
+int main()
+{
+    std::mutex mtx;
+
+    printf("== C++ threads tests ==\n");
+
+    // Create thread arguments
+    ThreadArgs args1{1, &mtx};
+    ThreadArgs args2{2, &mtx};
+
+    // Store threads and their return values
+    std::vector<std::thread> threads;
+    long ret1, ret2;
+
+    // Launch threads
+    std::thread t1([&]() { ret1 = simple_thread(args1); });
+    std::thread t2([&]() { ret2 = simple_thread(args2); });
+
+   threads.push_back(std::move(t1));
+   threads.push_back(std::move(t2));
+
+    // Wait for threads to finish
+   for (auto& t : threads) {
+       if (t.joinable()) {
+           t.join();
+       }
+   }
+
+    // Check return values
+   if (ret1 != 1) {
+       std::cout << "Unexpected return value for thread 1" << std::endl;
+   }
+   if (ret2 != 2) {
+       std::cout << "Unexpected return value for thread 2" << std::endl;
+   }
+
+    std::cout << "All threads finished" << std::endl;
+    return 0;
+}

From 753bdb818648fe1aaf378615517841ef32805af5 Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Mon, 5 Jan 2026 14:44:02 +0100
Subject: [PATCH 12/17] [C++] fix src format

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 so3/arch/arm32/thread.c        |  2 +-
 so3/arch/arm64/thread.c        |  2 +-
 so3/kernel/process.c           |  2 +-
 usr/src/tests/files_test.cpp   | 22 ++++----
 usr/src/tests/threads_test.cpp | 94 +++++++++++++++++-----------------
 5 files changed, 61 insertions(+), 61 deletions(-)

diff --git a/so3/arch/arm32/thread.c b/so3/arch/arm32/thread.c
index dc92101a4..9ec16090c 100644
--- a/so3/arch/arm32/thread.c
+++ b/so3/arch/arm32/thread.c
@@ -83,7 +83,7 @@ void arch_restart_user_thread(tcb_t *tcb, th_fn_t fn_entry, addr_t stack_top)
 	/* Reset all user's registers to zero except for PC, PSTATE and SP
 	 * which needs to be set to the properly start the thread.
 	 */
-	*user_regs = (cpu_regs_t) {
+	*user_regs = (cpu_regs_t){
 		.pc = (u32) fn_entry,
 		.psr = PSR_USR_MODE | PSR_I_BIT,
 		.sp_usr = stack_top,
diff --git a/so3/arch/arm64/thread.c b/so3/arch/arm64/thread.c
index 9ad64bae3..ca4ce1da4 100644
--- a/so3/arch/arm64/thread.c
+++ b/so3/arch/arm64/thread.c
@@ -79,7 +79,7 @@ void arch_restart_user_thread(tcb_t *tcb, th_fn_t fn_entry, addr_t stack_top)
 	/* Reset all user's registers to zero except for PC, PSTATE and SP
 	 * which needs to be set to the properly start the program
 	 */
-	*user_regs = (cpu_regs_t) {
+	*user_regs = (cpu_regs_t){
 		.pc = (u64) fn_entry,
 		.pstate = PSR_MODE_EL0t,
 		.sp_usr = stack_top,
diff --git a/so3/kernel/process.c b/so3/kernel/process.c
index ccc61a5f4..fe922f5cd 100644
--- a/so3/kernel/process.c
+++ b/so3/kernel/process.c
@@ -346,7 +346,7 @@ void create_root_process(void)
 		       (void *) __root_proc_end - (void *) __root_proc_start, false);
 
 	/* Start main user thread. */
-	thread_args = (clone_args_t) {
+	thread_args = (clone_args_t){
 		.name = "root_proc",
 		.pcb = pcb,
 		.stack = pcb->stack_top,
diff --git a/usr/src/tests/files_test.cpp b/usr/src/tests/files_test.cpp
index f5316b2db..731ed9686 100644
--- a/usr/src/tests/files_test.cpp
+++ b/usr/src/tests/files_test.cpp
@@ -1,17 +1,17 @@
 
 
-
 #include <fstream>
 #include <iostream>
 
-int main() {
-    std::ofstream file("example.txt");
-    if (!file) {
-        std::cerr << "Failed to open file\n";
-        return 1;
-    }
+int main()
+{
+	std::ofstream file("example.txt");
+	if (!file) {
+		std::cerr << "Failed to open file\n";
+		return 1;
+	}
 
-    file << "Hello from C++\n";
-    // file closes automatically (RAII)
-    return 0;
-}
\ No newline at end of file
+	file << "Hello from C++\n";
+	// file closes automatically
+	return 0;
+}
diff --git a/usr/src/tests/threads_test.cpp b/usr/src/tests/threads_test.cpp
index 5503c1e0e..bb2d77a4f 100644
--- a/usr/src/tests/threads_test.cpp
+++ b/usr/src/tests/threads_test.cpp
@@ -24,65 +24,65 @@
 #include <unistd.h>
 
 struct ThreadArgs {
-    long thread_id;
-    std::mutex* mtx;
+	long thread_id;
+	std::mutex *mtx;
 };
 
 // Thread function
 long simple_thread(ThreadArgs args)
 {
-    std::cout << "Thread " << args.thread_id << ": Executing" << std::endl;
+	std::cout << "Thread " << args.thread_id << ": Executing" << std::endl;
 
-    // Lock the mutex
-    args.mtx->lock();
-    std::cout << "Thread " << args.thread_id << ": Locked mutex" << std::endl;
+	// Lock the mutex
+	args.mtx->lock();
+	std::cout << "Thread " << args.thread_id << ": Locked mutex" << std::endl;
 
-    std::this_thread::sleep_for(std::chrono::seconds(3));
+	std::this_thread::sleep_for(std::chrono::seconds(3));
 
-    std::cout << "Thread " << args.thread_id << ": Unlocking mutex" << std::endl;
-    args.mtx->unlock();
+	std::cout << "Thread " << args.thread_id << ": Unlocking mutex" << std::endl;
+	args.mtx->unlock();
 
-    std::cout << "Thread " << args.thread_id << ": Thread finished" << std::endl;
+	std::cout << "Thread " << args.thread_id << ": Thread finished" << std::endl;
 
-    return args.thread_id;
+	return args.thread_id;
 }
 
 int main()
 {
-    std::mutex mtx;
-
-    printf("== C++ threads tests ==\n");
-
-    // Create thread arguments
-    ThreadArgs args1{1, &mtx};
-    ThreadArgs args2{2, &mtx};
-
-    // Store threads and their return values
-    std::vector<std::thread> threads;
-    long ret1, ret2;
-
-    // Launch threads
-    std::thread t1([&]() { ret1 = simple_thread(args1); });
-    std::thread t2([&]() { ret2 = simple_thread(args2); });
-
-   threads.push_back(std::move(t1));
-   threads.push_back(std::move(t2));
-
-    // Wait for threads to finish
-   for (auto& t : threads) {
-       if (t.joinable()) {
-           t.join();
-       }
-   }
-
-    // Check return values
-   if (ret1 != 1) {
-       std::cout << "Unexpected return value for thread 1" << std::endl;
-   }
-   if (ret2 != 2) {
-       std::cout << "Unexpected return value for thread 2" << std::endl;
-   }
-
-    std::cout << "All threads finished" << std::endl;
-    return 0;
+	std::mutex mtx;
+
+	printf("== C++ threads tests ==\n");
+
+	// Create thread arguments
+	ThreadArgs args1{ 1, &mtx };
+	ThreadArgs args2{ 2, &mtx };
+
+	// Store threads and their return values
+	std::vector<std::thread> threads;
+	long ret1, ret2;
+
+	// Launch threads
+	std::thread t1([&]() { ret1 = simple_thread(args1); });
+	std::thread t2([&]() { ret2 = simple_thread(args2); });
+
+	threads.push_back(std::move(t1));
+	threads.push_back(std::move(t2));
+
+	// Wait for threads to finish
+	for (auto &t : threads) {
+		if (t.joinable()) {
+			t.join();
+		}
+	}
+
+	// Check return values
+	if (ret1 != 1) {
+		std::cout << "Unexpected return value for thread 1" << std::endl;
+	}
+	if (ret2 != 2) {
+		std::cout << "Unexpected return value for thread 2" << std::endl;
+	}
+
+	std::cout << "All threads finished" << std::endl;
+	return 0;
 }

From ae9e0ff2b514695441fea1507e05ce88245641b6 Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Mon, 5 Jan 2026 14:49:31 +0100
Subject: [PATCH 13/17] Fix clang format

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 so3/arch/arm32/thread.c | 2 +-
 so3/arch/arm64/thread.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/so3/arch/arm32/thread.c b/so3/arch/arm32/thread.c
index 9ec16090c..dc92101a4 100644
--- a/so3/arch/arm32/thread.c
+++ b/so3/arch/arm32/thread.c
@@ -83,7 +83,7 @@ void arch_restart_user_thread(tcb_t *tcb, th_fn_t fn_entry, addr_t stack_top)
 	/* Reset all user's registers to zero except for PC, PSTATE and SP
 	 * which needs to be set to the properly start the thread.
 	 */
-	*user_regs = (cpu_regs_t){
+	*user_regs = (cpu_regs_t) {
 		.pc = (u32) fn_entry,
 		.psr = PSR_USR_MODE | PSR_I_BIT,
 		.sp_usr = stack_top,
diff --git a/so3/arch/arm64/thread.c b/so3/arch/arm64/thread.c
index ca4ce1da4..9ad64bae3 100644
--- a/so3/arch/arm64/thread.c
+++ b/so3/arch/arm64/thread.c
@@ -79,7 +79,7 @@ void arch_restart_user_thread(tcb_t *tcb, th_fn_t fn_entry, addr_t stack_top)
 	/* Reset all user's registers to zero except for PC, PSTATE and SP
 	 * which needs to be set to the properly start the program
 	 */
-	*user_regs = (cpu_regs_t){
+	*user_regs = (cpu_regs_t) {
 		.pc = (u64) fn_entry,
 		.pstate = PSR_MODE_EL0t,
 		.sp_usr = stack_top,

From 5a220ca3651e8618bb163fa6a16e65e9f22a5058 Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Mon, 5 Jan 2026 14:53:38 +0100
Subject: [PATCH 14/17] clang format again

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 so3/kernel/process.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/so3/kernel/process.c b/so3/kernel/process.c
index fe922f5cd..ccc61a5f4 100644
--- a/so3/kernel/process.c
+++ b/so3/kernel/process.c
@@ -346,7 +346,7 @@ void create_root_process(void)
 		       (void *) __root_proc_end - (void *) __root_proc_start, false);
 
 	/* Start main user thread. */
-	thread_args = (clone_args_t){
+	thread_args = (clone_args_t) {
 		.name = "root_proc",
 		.pcb = pcb,
 		.stack = pcb->stack_top,

From 1f1cad5eddf99ba26ac132840bc7bf5ac33dfa84 Mon Sep 17 00:00:00 2001
From: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
Date: Fri, 16 Jan 2026 11:30:05 +0100
Subject: [PATCH 15/17] [C++] Add Copyright in src file + clean-up

Signed-off-by: Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
---
 usr/build.sh                 |  1 -
 usr/src/tests/files_test.cpp | 18 +++++++++++++++++-
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/usr/build.sh b/usr/build.sh
index d596d04dc..3b089289a 100755
--- a/usr/build.sh
+++ b/usr/build.sh
@@ -15,7 +15,6 @@ usage() {
 strip_debug_info()
 {
   # retrieve the correct objcop tool
-  # if [ "$1" == "virt32" -o "$1" == "rpi4" ]; then
   if [ "$1" = "virt32" ] || [ "$1" = "rpi4" ]; then
     OBJCOPY="arm-linux-musleabihf-objcopy"
   else
diff --git a/usr/src/tests/files_test.cpp b/usr/src/tests/files_test.cpp
index 731ed9686..e5ac0c9c3 100644
--- a/usr/src/tests/files_test.cpp
+++ b/usr/src/tests/files_test.cpp
@@ -1,4 +1,20 @@
-
+/*
+ * Copyright (C) 2025 Jean-Pierre Miceli <jean-pierre.miceli@heig-vd.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
 
 #include <fstream>
 #include <iostream>

From cff6f12fc36285b19a035c9d7f6dc2e60ad34d22 Mon Sep 17 00:00:00 2001
From: Clement Dieperink <clement.dieperink@heig-vd.ch>
Date: Fri, 16 Jan 2026 18:51:11 +0100
Subject: [PATCH 16/17] rework elf loading to ensure all section are loaded and
 added kuser helpers

---
 so3/arch/arm32/Makefile       |  1 +
 so3/arch/arm32/kuser_helper.S | 99 +++++++++++++++++++++++++++++++++++
 so3/fs/elf.c                  | 21 +++++---
 so3/include/elf.h             |  6 ++-
 so3/kernel/process.c          | 98 ++++++++--------------------------
 so3/mm/memory.c               |  8 +++
 usr/aarch64-linux-musl.cmake  |  1 +
 usr/arm-linux-musl.cmake      |  3 +-
 8 files changed, 152 insertions(+), 85 deletions(-)
 create mode 100644 so3/arch/arm32/kuser_helper.S

diff --git a/so3/arch/arm32/Makefile b/so3/arch/arm32/Makefile
index 1b03fb8e0..1dd060edd 100644
--- a/so3/arch/arm32/Makefile
+++ b/so3/arch/arm32/Makefile
@@ -7,6 +7,7 @@ obj-y += vfp.o
 obj-y += backtrace.o backtrace_asm.o
 obj-y += smccc-call.o
 obj-y += syscalls.o
+obj-y += kuser_helper.o
 
 obj-y += lib/
 
diff --git a/so3/arch/arm32/kuser_helper.S b/so3/arch/arm32/kuser_helper.S
new file mode 100644
index 000000000..0a3265694
--- /dev/null
+++ b/so3/arch/arm32/kuser_helper.S
@@ -0,0 +1,99 @@
+/*
+ *  Copyright (C) 2025 Clément Dieperink <clement.dieperink@heig-vd.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * This file is copied from the Linux kernel with some small adaptation for SO3.
+ * Original file from Linux 6.18 : linux/arch/arm/kernel/entry-armv.S:652-842
+ */
+
+
+/*
+ * User helpers.
+ *
+ * Each segment is 32-byte aligned and will be moved to the top of the high
+ * vector page.  New segments (if ever needed) must be added in front of
+ * existing ones.  This mechanism should be used only for things that are
+ * really small and justified, and not be abused freely.
+ *
+ * See Documentation/arch/arm/kernel_user_helpers.rst for formal definitions.
+ */
+	.macro	usr_ret, reg
+	ret	\reg
+	.endm
+
+	.macro	kuser_pad, sym, size
+	.if	(. - \sym) & 3
+	.rept	4 - (. - \sym) & 3
+	.byte	0
+	.endr
+	.endif
+	.rept	(\size - (. - \sym)) / 4
+	.word	0xe7fddef1
+	.endr
+	.endm
+
+	.align	5
+	.globl	__kuser_helper_start
+__kuser_helper_start:
+
+/*
+ * Due to the length of some sequences, __kuser_cmpxchg64 spans 2 regular
+ * kuser "slots", therefore 0xffff0f80 is not used as a valid entry point.
+ */
+
+	@ Not implemented as eorseq doesn't compile
+__kuser_cmpxchg64:				@ 0xffff0f60
+
+	kuser_pad __kuser_cmpxchg64, 64
+
+__kuser_memory_barrier:				@ 0xffff0fa0
+	dmb	ish
+	mov	pc, lr
+
+	kuser_pad __kuser_memory_barrier, 32
+
+__kuser_cmpxchg:				@ 0xffff0fc0
+
+	dmb	ish
+1:	ldrex	r3, [r2]
+	subs	r3, r3, r0
+	strexeq	r3, r1, [r2]
+	teqeq	r3, #1
+	beq	1b
+	rsbs	r0, r3, #0
+	/* beware -- each __kuser slot must be 8 instructions max */
+	b	__kuser_memory_barrier
+
+	kuser_pad __kuser_cmpxchg, 32
+
+	@ Not implemented here as syscall already exist
+__kuser_get_tls:				@ 0xffff0fe0
+	mov	r0, #0
+	mov	pc, lr
+	kuser_pad __kuser_get_tls, 16
+	.rep	3
+	.word	0			@ 0xffff0ff0 software TLS value, then
+	.endr				@ pad up to __kuser_helper_version
+
+__kuser_helper_version:				@ 0xffff0ffc
+	.word	((__kuser_helper_end - __kuser_helper_start) >> 5)
+
+	.globl	__kuser_helper_end
+__kuser_helper_end:
diff --git a/so3/fs/elf.c b/so3/fs/elf.c
index 5899debd2..24d20e702 100644
--- a/so3/fs/elf.c
+++ b/so3/fs/elf.c
@@ -166,7 +166,7 @@ void elf_load_segments(elf_img_info_t *elf_img_info)
 {
 	size_t i;
 	size_t segment_start, segment_end;
-	size_t page_start, page_end;
+	size_t min_segment_start, max_segment_end;
 
 	/* Segments */
 #ifdef CONFIG_ARCH_ARM32
@@ -189,7 +189,8 @@ void elf_load_segments(elf_img_info_t *elf_img_info)
 	LOG_DEBUG("sizeof(struct elf64_phdr): %d bytes\n", sizeof(struct elf64_phdr));
 #endif
 
-	elf_img_info->segment_page_count = 0;
+	min_segment_start = -1;
+	max_segment_end = 0;
 	for (i = 0; i < elf_img_info->header->e_phnum; i++) {
 #ifdef CONFIG_ARCH_ARM32
 		memcpy(elf_img_info->segments + i,
@@ -202,16 +203,22 @@ void elf_load_segments(elf_img_info_t *elf_img_info)
 #endif
 
 		if (elf_img_info->segments[i].p_type == PT_LOAD) {
-			/* Don't use only p_memsz to get page count as p_vaddr can be unaligned and additionnal page will be needed. */
 			segment_start = elf_img_info->segments[i].p_vaddr;
 			segment_end = segment_start + elf_img_info->segments[i].p_memsz;
 
-			page_start = segment_start >> PAGE_SHIFT;
-			page_end = (segment_end + PAGE_SIZE) >> PAGE_SHIFT;
-
-			elf_img_info->segment_page_count += page_end - page_start;
+			min_segment_start = min(min_segment_start, (segment_start & PAGE_MASK));
+			max_segment_end = max(max_segment_end, segment_end);
 		}
 	}
+
+	if (max_segment_end != -1) {
+		elf_img_info->segment_start_vaddr = min_segment_start;
+		elf_img_info->segment_end_vaddr = max_segment_end;
+	} else {
+		elf_img_info->segment_start_vaddr = 0;
+		elf_img_info->segment_end_vaddr = 0;
+	}
+
 	LOG_DEBUG("segments use %d virtual pages\n", elf_img_info->segment_page_count);
 
 	for (i = 0; i < elf_img_info->header->e_phnum; i++) {
diff --git a/so3/include/elf.h b/so3/include/elf.h
index 688bbb678..61b6d8472 100644
--- a/so3/include/elf.h
+++ b/so3/include/elf.h
@@ -33,7 +33,8 @@ struct elf_img_info {
 	Elf32_Phdr *segments; /* program header */
 	char **section_names;
 	void *file_buffer;
-	uint32_t segment_page_count;
+	addr_t segment_start_vaddr;
+	addr_t segment_end_vaddr;
 };
 
 typedef Elf32_Off elf_addr_t;
@@ -46,7 +47,8 @@ struct elf_img_info {
 	Elf64_Phdr *segments; /* program header */
 	char **section_names;
 	void *file_buffer;
-	uint64_t segment_page_count;
+	addr_t segment_start_vaddr;
+	addr_t segment_end_vaddr;
 };
 
 typedef Elf64_Off elf_addr_t;
diff --git a/so3/kernel/process.c b/so3/kernel/process.c
index ccc61a5f4..2646e5113 100644
--- a/so3/kernel/process.c
+++ b/so3/kernel/process.c
@@ -73,14 +73,6 @@ char *proc_state_str(proc_state_t state)
 static uint32_t pid_current = 1;
 static pcb_t *root_process = NULL; /* root process */
 
-/* only the following sections are supported */
-static const char *supported_section_names[] = {
-	".init",       ".text",	      ".rodata",      ".data",	   ".sbss",
-	".bss",	       ".scommon",    ".fini",	      ".eh_frame", ".gcc_except_table",
-	".init_array", ".fini_array", ".data.rel.ro", ".got",	   ".got.plt",
-};
-#define SUPPORTED_SECTION_COUNT (sizeof(supported_section_names) / sizeof(supported_section_names[0]))
-
 /*
  * Find a process (pcb_t) from its pid.
  * Return NULL if no process has been found.
@@ -511,16 +503,13 @@ void post_setup_image(args_env_t *args_env, elf_img_info_t *elf_img_info)
 	/* This should contains a bitmask of hardware capabilities */
 	NEW_AUX_ENT(AT_HWCAP, HWCAP_ELF);
 
-	/* Those value should come from elf_img_info->header, but as user application
-	 * are compiled with linker option -N, the program header (PHDR) isn't in a PT_LOAD
-	 * segment meaning it will not be copied in userspace.
-	 * The main effect of this is that variable in thread local storage will not be possible.
-	 * Those variable are *flaged* with __thread (i.e `__thread int n;`) and aren't used for now.
-	 * This header is also used for dynamically linking, which isn't supported by SO3 anyway.
+	/* Set PHDR information, so userspace can retrieve TLS information.
+	 * Due to how userspace application are built the PHDR segments is missing and so
+	 * we need to manually compute its address.
 	 */
-	NEW_AUX_ENT(AT_PHDR, 0);
-	NEW_AUX_ENT(AT_PHENT, 0);
-	NEW_AUX_ENT(AT_PHNUM, 0);
+	NEW_AUX_ENT(AT_PHDR, elf_img_info->header->e_phoff + (elf_img_info->segment_start_vaddr & PAGE_MASK));
+	NEW_AUX_ENT(AT_PHENT, sizeof(*elf_img_info->segments));
+	NEW_AUX_ENT(AT_PHNUM, elf_img_info->header->e_phnum);
 
 	/* NULL termination */
 	NEW_AUX_ENT(AT_NULL, 0);
@@ -611,17 +600,18 @@ int setup_proc_image_replace(elf_img_info_t *elf_img_info, pcb_t *pcb, int argc,
          * application must start at 0x1000 (at the lowest).
          */
 
-	pcb->page_count += elf_img_info->segment_page_count;
+	page_count = ((elf_img_info->segment_end_vaddr - elf_img_info->segment_start_vaddr) >> PAGE_SHIFT) + 1;
+	pcb->page_count += page_count;
 
 	/* Map the elementary sections (text, data, bss) */
-	allocate_page(pcb, (uint32_t) (elf_img_info->header->e_entry & PAGE_MASK), elf_img_info->segment_page_count, true);
+	allocate_page(pcb, elf_img_info->segment_start_vaddr, page_count, true);
 
 	LOG_DEBUG("entry point: 0x%08x\n", elf_img_info->header->e_entry);
 	LOG_DEBUG("page count: 0x%08x\n", pcb->page_count);
 
 	/* Maximum heap size */
 	page_count = ALIGN_UP(HEAP_SIZE, PAGE_SIZE) >> PAGE_SHIFT;
-	pcb->heap_base = (elf_img_info->header->e_entry & PAGE_MASK) + (pcb->page_count + 1) * PAGE_SIZE;
+	pcb->heap_base = (elf_img_info->segment_end_vaddr & PAGE_MASK) + PAGE_SIZE;
 	pcb->heap_pointer = pcb->heap_base;
 	pcb->page_count += page_count;
 
@@ -645,12 +635,12 @@ int setup_proc_image_replace(elf_img_info_t *elf_img_info, pcb_t *pcb, int argc,
 /* load sections from each loadable segment into the process' virtual pages */
 void load_process(elf_img_info_t *elf_img_info)
 {
-	unsigned long section_start, section_end;
-	unsigned long segment_start, segment_end;
-	int i, j, k, l;
-	bool section_supported;
-	char section_base_name[16];
-	int section_name_dots;
+	int i;
+
+	/* Manually copy the PHDR as no segement/section contains it. */
+	memcpy((void *) (elf_img_info->header->e_phoff + (elf_img_info->segment_start_vaddr & PAGE_MASK)),
+	       elf_img_info->file_buffer + elf_img_info->header->e_phoff,
+	       elf_img_info->header->e_phnum * elf_img_info->header->e_phentsize);
 
 	/* Loading the different segments */
 	for (i = 0; i < elf_img_info->header->e_phnum; i++) {
@@ -658,56 +648,14 @@ void load_process(elf_img_info_t *elf_img_info)
 			/* Skip unloadable segments */
 			continue;
 
-		segment_start = elf_img_info->segments[i].p_offset;
-		segment_end = segment_start + elf_img_info->segments[i].p_memsz;
-
-		/* Sections */
-		for (j = 0; j < elf_img_info->header->e_shnum; j++) {
-			section_start = elf_img_info->sections[j].sh_offset;
-			section_end = section_start + elf_img_info->sections[j].sh_size;
-
-			/* Verify if the section is part of this segment */
-			if ((section_start < segment_start) || (section_end > segment_end))
-				continue;
-
-			/* Copy only base name of the section */
-			l = 0;
-			section_name_dots = 0;
-			do {
-				section_base_name[l] = elf_img_info->section_names[j][l];
-				if (section_base_name[l] == '.' && section_name_dots++)
-					break; // Base name stops at second '.'
-			} while (section_base_name[l++] != '\0');
-
-			/* Terminate string correctly (replace second '.' if stopped by it) */
-			section_base_name[l] = '\0';
-
-			/* Not all sections are supported */
-			section_supported = false;
-			for (k = 0; k < SUPPORTED_SECTION_COUNT; k++) {
-				if (!strcmp(section_base_name, supported_section_names[k])) {
-					section_supported = true;
-					break;
-				}
-			}
-
-			if (!section_supported) {
-				LOG_DEBUG("Section %s not loaded: unsupported name\n", elf_img_info->section_names[j]);
-				continue;
-			}
+		/* Copy all required data. */
+		memcpy((void *) elf_img_info->segments[i].p_vaddr,
+		       (void *) (elf_img_info->file_buffer + elf_img_info->segments[i].p_offset),
+		       elf_img_info->segments[i].p_filesz);
 
-			/* Load this section into the process' virtual memory */
-			if (elf_img_info->sections[j].sh_type == SHT_NOBITS)
-				/* unless it were not stored in the file (.bss)
-                                 */
-				continue;
-
-			/* Real load of contents in the user space memory of the
-                         * process */
-			memcpy((void *) elf_img_info->sections[j].sh_addr,
-			       (void *) (elf_img_info->file_buffer + elf_img_info->sections[j].sh_offset),
-			       elf_img_info->sections[j].sh_size);
-		}
+		/* Set remaining byte (bss) to zero. */
+		memset((void *) (elf_img_info->segments[i].p_vaddr + elf_img_info->segments[i].p_filesz), 0,
+		       elf_img_info->segments[i].p_memsz - elf_img_info->segments[i].p_filesz);
 	}
 
 	/* Make sure all data are flushed for future context switch. */
diff --git a/so3/mm/memory.c b/so3/mm/memory.c
index 8e9181b1b..98df46f52 100644
--- a/so3/mm/memory.c
+++ b/so3/mm/memory.c
@@ -434,6 +434,11 @@ void memory_init(void)
 
 #if defined(CONFIG_ARCH_ARM32)
 	addr_t vectors_paddr;
+
+	/* kuser helper are special function provided to userspace by the kernel. */
+	addr_t kuser_sz;
+	extern char __kuser_helper_start[];
+	extern char __kuser_helper_end[];
 #endif
 	void *new_sys_root_pgtable;
 
@@ -496,6 +501,9 @@ void memory_init(void)
 	create_mapping(NULL, VECTOR_VADDR, vectors_paddr, PAGE_SIZE, true);
 
 	memcpy((void *) VECTOR_VADDR, (void *) &__vectors_start, (void *) &__vectors_end - (void *) &__vectors_start);
+
+	kuser_sz = __kuser_helper_end - __kuser_helper_start;
+	memcpy((void *) (VECTOR_VADDR + PAGE_SIZE - kuser_sz), __kuser_helper_start, kuser_sz);
 #endif
 
 	set_pgtable(__sys_root_pgtable);
diff --git a/usr/aarch64-linux-musl.cmake b/usr/aarch64-linux-musl.cmake
index f7c353062..34f5499a7 100644
--- a/usr/aarch64-linux-musl.cmake
+++ b/usr/aarch64-linux-musl.cmake
@@ -21,6 +21,7 @@ set(CMAKE_CXX_COMPILER "aarch64-linux-musl-g++")
 set(CMAKE_ASM_COMPILER "aarch64-linux-musl-gcc")
 
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -std=c99 -D_GNU_SOURCE -D__ARM64__ -fno-common")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -D_GNU_SOURCE -D__ARM64__ -fno-common")
 
 set(CMAKE_ASM_FLAGS "-D__ARM64__ -D__ASSEMBLY__")
 
diff --git a/usr/arm-linux-musl.cmake b/usr/arm-linux-musl.cmake
index f148c3542..768c06320 100644
--- a/usr/arm-linux-musl.cmake
+++ b/usr/arm-linux-musl.cmake
@@ -21,7 +21,8 @@ set(CMAKE_CXX_COMPILER "arm-linux-musleabihf-g++")
 set(CMAKE_ASM_COMPILER "arm-linux-musleabihf-gcc")
 
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -std=c99 -D_GNU_SOURCE -D__ARM__ -marm -mno-thumb-interwork -ffreestanding -fno-common")
- 
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -D_GNU_SOURCE -D__ARM__ -marm -mno-thumb-interwork -ffreestanding -fno-common")
+
 set(CMAKE_ASM_FLAGS "-D__ARM__ -D__ASSEMBLY__")
 
 set(CMAKE_LINKER "arm-linux-musleabihf-ld")

From 0d70faf795a383fab46f8e467e7a1cf72490a730 Mon Sep 17 00:00:00 2001
From: Clement Dieperink <clement.dieperink@heig-vd.ch>
Date: Fri, 16 Jan 2026 18:51:52 +0100
Subject: [PATCH 17/17] fix copyright

---
 so3/arch/arm32/kuser_helper.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/so3/arch/arm32/kuser_helper.S b/so3/arch/arm32/kuser_helper.S
index 0a3265694..765a3976f 100644
--- a/so3/arch/arm32/kuser_helper.S
+++ b/so3/arch/arm32/kuser_helper.S
@@ -1,5 +1,5 @@
 /*
- *  Copyright (C) 2025 Clément Dieperink <clement.dieperink@heig-vd.ch>
+ *  Copyright (C) 2026 Clément Dieperink <clement.dieperink@heig-vd.ch>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as