From 397630f9ffd836c9ac939ad4d40093cd640ab1a1 Mon Sep 17 00:00:00 2001
From: Diego Ferrari <services@diferrari.com>
Date: Sat, 27 Sep 2025 00:00:00 +0000
Subject: [PATCH 1/8] [CONT_SWITCH] cpec (current process execution context)
 register

---
 kernel/process/context_switch.S |  5 ++++-
 kernel/process/scheduler.c      | 14 ++++++++------
 kernel/process/syscall.c        |  1 +
 kernel/process/syscall.h        |  3 ++-
 4 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/kernel/process/context_switch.S b/kernel/process/context_switch.S
index e03b73cb..30c76dd0 100644
--- a/kernel/process/context_switch.S
+++ b/kernel/process/context_switch.S
@@ -1,7 +1,8 @@
 .global save_context
 save_context:
-    // x0: pointer to process_t
 
+    ldr x0, =cpec
+    ldr x0, [x0]
     // Save general-purpose registers x1-x30 (excluding x0 which holds the pointer)
     stp x1, x2, [x0, #(8 * 0)]
     stp x3, x4, [x0, #(8 * 2)]
@@ -37,6 +38,8 @@ save_pc_interrupt:
 
 .global restore_context
 restore_context:
+    ldr x0, =cpec
+    ldr x0, [x0]
     // Restore general-purpose registers
     ldp x1, x2, [x0, #(8 * 0)]
     ldp x3, x4, [x0, #(8 * 2)]
diff --git a/kernel/process/scheduler.c b/kernel/process/scheduler.c
index 0062c847..5b495e38 100644
--- a/kernel/process/scheduler.c
+++ b/kernel/process/scheduler.c
@@ -15,9 +15,9 @@
 #include "memory/mmu.h"
 #include "process/syscall.h"
 
-extern void save_context(process_t* proc);
-extern void save_pc_interrupt(process_t* proc);
-extern void restore_context(process_t* proc);
+extern void save_context(uintptr_t ptr);
+extern void save_pc_interrupt(uintptr_t ptr);
+extern void restore_context(uintptr_t ptr);
 
 //TODO: use queues, eliminate the max procs limitation
 process_t processes[MAX_PROCS];
@@ -49,11 +49,11 @@ typedef struct proc_open_file {
 void* proc_page;
 
 void save_context_registers(){
-    save_context(&processes[current_proc]);
+    save_context(cpec);
 }
 
 void save_return_address_interrupt(){
-    save_pc_interrupt(&processes[current_proc]);
+    save_pc_interrupt(cpec);
 }
 
 void switch_proc(ProcSwitchReason reason) {
@@ -66,6 +66,7 @@ void switch_proc(ProcSwitchReason reason) {
     }
 
     current_proc = next_proc;
+    cpec = (uintptr_t)&processes[current_proc];
     timer_reset(processes[current_proc].priority);
     process_restore();
 }
@@ -76,7 +77,7 @@ void save_syscall_return(uint64_t value){
 
 void process_restore(){
     syscall_depth--;
-    restore_context(&processes[current_proc]);
+    restore_context(cpec);
 }
 
 bool start_scheduler(){
@@ -159,6 +160,7 @@ void reset_process(process_t *proc){
 void init_main_process(){
     proc_page = palloc(0x1000, MEM_PRIV_KERNEL, MEM_RW, false);
     process_t* proc = &processes[0];
+    cpec = (uintptr_t)&processes[0];
     proc->id = next_proc_index++;
     proc->state = BLOCKED;
     proc->heap = (uintptr_t)palloc(0x1000, MEM_PRIV_KERNEL, MEM_RW, false);
diff --git a/kernel/process/syscall.c b/kernel/process/syscall.c
index c3491513..7c541586 100644
--- a/kernel/process/syscall.c
+++ b/kernel/process/syscall.c
@@ -21,6 +21,7 @@
 #include "bin/bin_mod.h"
 
 int syscall_depth = 0;
+uintptr_t cpec;
 
 //TODO: What happens if we pass another process' data in here?
 //TODO: make indexmap in c and it can be used here
diff --git a/kernel/process/syscall.h b/kernel/process/syscall.h
index 42515e59..61c24fdc 100644
--- a/kernel/process/syscall.h
+++ b/kernel/process/syscall.h
@@ -2,4 +2,5 @@
 
 #include "types.h"
 
-extern int syscall_depth;
\ No newline at end of file
+extern int syscall_depth;
+extern uintptr_t cpec;
\ No newline at end of file

From 60a9c09d3a5e633ef4bdd004cc4bb950ff5d8bb7 Mon Sep 17 00:00:00 2001
From: Diego Ferrari <services@diferrari.com>
Date: Sun, 28 Sep 2025 00:00:00 +0000
Subject: [PATCH 2/8] [CONT_SWITCH] saving to cpec

---
 kernel/Makefile                          |  1 +
 kernel/exceptions/exception_vectors_as.S |  5 ++++
 kernel/exceptions/irq.c                  |  1 -
 kernel/process/context.inc               | 28 +++++++++++++++++++++
 kernel/process/context_switch.S          | 31 ------------------------
 kernel/process/scheduler.c               |  5 ----
 kernel/process/scheduler.h               |  1 -
 kernel/process/syscall.c                 |  1 -
 kernel/process/syscall_as.S              |  5 ++++
 shared/Makefile                          |  2 +-
 10 files changed, 40 insertions(+), 40 deletions(-)
 create mode 100644 kernel/process/context.inc

diff --git a/kernel/Makefile b/kernel/Makefile
index eb2511d8..00f5d147 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -50,5 +50,6 @@ $(BUILD_DIR)/%.o: %.cpp
 
 clean:
 	$(RM) $(CLEAN_OBJS) $(CLEAN_DEPS) $(ELF) $(TARGET)
+	$(RM) -r $(BUILD_DIR)
 
 -include $(DEP)
diff --git a/kernel/exceptions/exception_vectors_as.S b/kernel/exceptions/exception_vectors_as.S
index ac68f059..4021ed7e 100644
--- a/kernel/exceptions/exception_vectors_as.S
+++ b/kernel/exceptions/exception_vectors_as.S
@@ -1,3 +1,5 @@
+#include "process/context.inc"
+
 .section .vectors, "a", %progbits
 .align 11
 .global exception_vectors
@@ -58,5 +60,8 @@ irq_el1_asm_handler:
     mov x16, x3
     mov x13, x29
     mov x12, x30
+
+    save_ctx 
+    
     b irq_el1_handler
     eret
\ No newline at end of file
diff --git a/kernel/exceptions/irq.c b/kernel/exceptions/irq.c
index 7936e841..5166b083 100644
--- a/kernel/exceptions/irq.c
+++ b/kernel/exceptions/irq.c
@@ -73,7 +73,6 @@ void disable_interrupt(){
 }
 
 void irq_el1_handler() {
-    save_context_registers();
     save_return_address_interrupt();
     syscall_depth++;
     uint32_t irq;
diff --git a/kernel/process/context.inc b/kernel/process/context.inc
new file mode 100644
index 00000000..39f405b4
--- /dev/null
+++ b/kernel/process/context.inc
@@ -0,0 +1,28 @@
+.macro save_ctx
+ldr x0, =cpec
+ldr x0, [x0]
+// Save general-purpose registers x1-x30 (excluding x0 which holds the pointer)
+stp x1, x2, [x0, #(8 * 0)]
+stp x3, x4, [x0, #(8 * 2)]
+stp x5, x6, [x0, #(8 * 4)]
+stp x7, x8, [x0, #(8 * 6)]
+stp x9, x10, [x0, #(8 * 8)]
+stp x11, x12, [x0, #(8 * 10)]
+stp x13, x14, [x0, #(8 * 12)]
+stp x15, x16, [x0, #(8 * 14)]
+stp x17, x18, [x0, #(8 * 16)]
+stp x19, x20, [x0, #(8 * 18)]
+stp x21, x22, [x0, #(8 * 20)]
+stp x23, x24, [x0, #(8 * 22)]
+stp x25, x26, [x0, #(8 * 24)]
+stp x27, x28, [x0, #(8 * 26)]
+stp x29, x30, [x0, #(8 * 28)]
+
+// SP
+str x11, [x0, #(8 * 31)]
+
+//Status bits
+and x10, x10, 0xFFF
+str x10, [x0, #(8 * 33)]
+
+.endm
\ No newline at end of file
diff --git a/kernel/process/context_switch.S b/kernel/process/context_switch.S
index 30c76dd0..8e21879a 100644
--- a/kernel/process/context_switch.S
+++ b/kernel/process/context_switch.S
@@ -1,34 +1,3 @@
-.global save_context
-save_context:
-
-    ldr x0, =cpec
-    ldr x0, [x0]
-    // Save general-purpose registers x1-x30 (excluding x0 which holds the pointer)
-    stp x1, x2, [x0, #(8 * 0)]
-    stp x3, x4, [x0, #(8 * 2)]
-    stp x5, x6, [x0, #(8 * 4)]
-    stp x7, x8, [x0, #(8 * 6)]
-    stp x9, x10, [x0, #(8 * 8)]
-    stp x11, x12, [x0, #(8 * 10)]
-    stp x13, x14, [x0, #(8 * 12)]
-    stp x15, x16, [x0, #(8 * 14)]
-    stp x17, x18, [x0, #(8 * 16)]
-    stp x19, x20, [x0, #(8 * 18)]
-    stp x21, x22, [x0, #(8 * 20)]
-    stp x23, x24, [x0, #(8 * 22)]
-    stp x25, x26, [x0, #(8 * 24)]
-    stp x27, x28, [x0, #(8 * 26)]
-    stp x29, x30, [x0, #(8 * 28)]
-
-    // SP
-    str x11, [x0, #(8 * 31)]
-
-    //Status bits
-    and x10, x10, 0xFFF
-    str x10, [x0, #(8 * 33)]
-
-    ret
-
 .global save_pc_interrupt
 save_pc_interrupt:
     mrs x1, elr_el1
diff --git a/kernel/process/scheduler.c b/kernel/process/scheduler.c
index 5b495e38..8cd539df 100644
--- a/kernel/process/scheduler.c
+++ b/kernel/process/scheduler.c
@@ -15,7 +15,6 @@
 #include "memory/mmu.h"
 #include "process/syscall.h"
 
-extern void save_context(uintptr_t ptr);
 extern void save_pc_interrupt(uintptr_t ptr);
 extern void restore_context(uintptr_t ptr);
 
@@ -48,10 +47,6 @@ typedef struct proc_open_file {
 
 void* proc_page;
 
-void save_context_registers(){
-    save_context(cpec);
-}
-
 void save_return_address_interrupt(){
     save_pc_interrupt(cpec);
 }
diff --git a/kernel/process/scheduler.h b/kernel/process/scheduler.h
index b62267d0..8ea84f2e 100644
--- a/kernel/process/scheduler.h
+++ b/kernel/process/scheduler.h
@@ -18,7 +18,6 @@ typedef enum {
 
 void switch_proc(ProcSwitchReason reason);
 bool start_scheduler();
-void save_context_registers();
 void save_return_address_interrupt();
 void init_main_process();
 process_t* init_process();
diff --git a/kernel/process/syscall.c b/kernel/process/syscall.c
index 7c541586..b464164c 100644
--- a/kernel/process/syscall.c
+++ b/kernel/process/syscall.c
@@ -261,7 +261,6 @@ void coredump(uint64_t esr, uint64_t elr, uint64_t far){
 }
 
 void sync_el0_handler_c(){
-    save_context_registers();
     save_return_address_interrupt();
 
     syscall_depth++;
diff --git a/kernel/process/syscall_as.S b/kernel/process/syscall_as.S
index b6399480..49fbe891 100644
--- a/kernel/process/syscall_as.S
+++ b/kernel/process/syscall_as.S
@@ -1,3 +1,5 @@
+#include "context.inc"
+
 .global sync_el0_handler_as
 
 //TODO: Rethink the registers used to be sequential both here and in context_switch and exception_vectors_as
@@ -29,5 +31,8 @@ sync_el0_handler_as:
     mov x16, x3
     mov x13, x29
     mov x12, x30
+
+    save_ctx
+
     b sync_el0_handler_c
     eret
\ No newline at end of file
diff --git a/shared/Makefile b/shared/Makefile
index 96d80111..593e7db5 100644
--- a/shared/Makefile
+++ b/shared/Makefile
@@ -40,8 +40,8 @@ $(BUILD_DIR)/%.o: %.cpp
 	@mkdir -p $(dir $@)
 	$(VCXX) $(CXXFLAGS) -c -MMD -MP $< -o $@
 
-# Might want to also delete the directories created inside BUILD_DIR
 clean:
 	$(RM) $(CLEAN_OBJS) $(CLEAN_DEPS) $(TARGET)
+	$(RM) -r $(BUILD_DIR)
 
 -include $(DEP)

From 2afb4e764422959a21c527aa9bf66493ac99a4c7 Mon Sep 17 00:00:00 2001
From: Diego Ferrari <services@diferrari.com>
Date: Sun, 28 Sep 2025 00:00:00 +0000
Subject: [PATCH 3/8] [CONT_SWITCH] unifying context switch functions

---
 kernel/exceptions/exception_vectors_as.S  | 37 ++++++----------------
 kernel/process/{context.inc => context.S} | 28 +++++++++++++++++
 kernel/process/syscall_as.S               | 38 -----------------------
 3 files changed, 37 insertions(+), 66 deletions(-)
 rename kernel/process/{context.inc => context.S} (57%)
 delete mode 100644 kernel/process/syscall_as.S

diff --git a/kernel/exceptions/exception_vectors_as.S b/kernel/exceptions/exception_vectors_as.S
index 4021ed7e..cb59d9d5 100644
--- a/kernel/exceptions/exception_vectors_as.S
+++ b/kernel/exceptions/exception_vectors_as.S
@@ -1,4 +1,4 @@
-#include "process/context.inc"
+#include "process/context.S"
 
 .section .vectors, "a", %progbits
 .align 11
@@ -33,35 +33,16 @@ exception_vectors:
 
 .global irq_el1_asm_handler
 irq_el1_asm_handler:
-    msr daifset, #2
-    mrs     x10, spsr_el1
-    lsr     x18, x10, #2
-    and     x18, x18, #0b11
-
-    cmp     x18, #1
-    b.eq    1f
-    cmp     x18, #0
-    b.eq    2f
-
-    b       3f
+    save_ctx 
 
-1:  mov     x11, sp
-    b       3f
+    b irq_el1_handler
+    eret
 
-2:  mrs     x11, sp_el0
-    ldr x18, =ksp
-    //TODO: in order to ensure we don't ovewrite any stack data, save it to its own global variable
-    mov sp, x18
+.global sync_el0_handler_as
 
-3:
-    mov x15, x0
-    mov x14, x1
-    mov x9, x2
-    mov x16, x3
-    mov x13, x29
-    mov x12, x30
+//TODO: Rethink the registers used to be sequential both here and in context_switch and exception_vectors_as
+sync_el0_handler_as:
+    save_ctx
 
-    save_ctx 
-    
-    b irq_el1_handler
+    b sync_el0_handler_c
     eret
\ No newline at end of file
diff --git a/kernel/process/context.inc b/kernel/process/context.S
similarity index 57%
rename from kernel/process/context.inc
rename to kernel/process/context.S
index 39f405b4..cd73d8a9 100644
--- a/kernel/process/context.inc
+++ b/kernel/process/context.S
@@ -1,4 +1,32 @@
 .macro save_ctx
+msr daifset, #2
+    mrs     x10, spsr_el1
+    lsr     x18, x10, #2
+    and     x18, x18, #0b11
+
+    cmp     x18, #1
+    b.eq    1f
+    cmp     x18, #0
+    b.eq    2f
+
+    b       3f
+
+1:  mov     x11, sp
+    b       3f
+
+2:  mrs     x11, sp_el0
+    ldr x18, =ksp
+    //TODO: in order to ensure we don't ovewrite any stack data, save it to its own global variable
+    mov sp, x18
+
+3:
+    mov x15, x0
+    mov x14, x1
+    mov x9, x2
+    mov x16, x3
+    mov x13, x29
+    mov x12, x30
+    
 ldr x0, =cpec
 ldr x0, [x0]
 // Save general-purpose registers x1-x30 (excluding x0 which holds the pointer)
diff --git a/kernel/process/syscall_as.S b/kernel/process/syscall_as.S
deleted file mode 100644
index 49fbe891..00000000
--- a/kernel/process/syscall_as.S
+++ /dev/null
@@ -1,38 +0,0 @@
-#include "context.inc"
-
-.global sync_el0_handler_as
-
-//TODO: Rethink the registers used to be sequential both here and in context_switch and exception_vectors_as
-sync_el0_handler_as:
-    msr daifset, #2
-    mrs     x10, spsr_el1
-    lsr     x18, x10, #2
-    and     x18, x18, #0b11
-
-    cmp     x18, #1
-    b.eq    1f
-    cmp     x18, #0
-    b.eq    2f
-
-    b       3f
-
-1:  mov     x11, sp
-    b       3f
-
-2:  mrs     x11, sp_el0
-    ldr x18, =ksp
-    //TODO: in order to ensure we don't ovewrite any stack data, save it to its own global variable
-    mov sp, x18
-
-3:
-    mov x15, x0
-    mov x14, x1
-    mov x9, x2
-    mov x16, x3
-    mov x13, x29
-    mov x12, x30
-
-    save_ctx
-
-    b sync_el0_handler_c
-    eret
\ No newline at end of file

From cd88a3661163859029838ba93274a26fec2310f4 Mon Sep 17 00:00:00 2001
From: Diego Ferrari <services@diferrari.com>
Date: Sun, 28 Sep 2025 00:00:00 +0000
Subject: [PATCH 4/8] [CONT_SWITCH] renamed file

---
 kernel/exceptions/exception_vectors_as.S     | 3 +--
 kernel/process/{context.S => context_save.S} | 0
 2 files changed, 1 insertion(+), 2 deletions(-)
 rename kernel/process/{context.S => context_save.S} (100%)

diff --git a/kernel/exceptions/exception_vectors_as.S b/kernel/exceptions/exception_vectors_as.S
index cb59d9d5..e22f7e77 100644
--- a/kernel/exceptions/exception_vectors_as.S
+++ b/kernel/exceptions/exception_vectors_as.S
@@ -1,4 +1,4 @@
-#include "process/context.S"
+#include "process/context_save.S"
 
 .section .vectors, "a", %progbits
 .align 11
@@ -39,7 +39,6 @@ irq_el1_asm_handler:
     eret
 
 .global sync_el0_handler_as
-
 //TODO: Rethink the registers used to be sequential both here and in context_switch and exception_vectors_as
 sync_el0_handler_as:
     save_ctx
diff --git a/kernel/process/context.S b/kernel/process/context_save.S
similarity index 100%
rename from kernel/process/context.S
rename to kernel/process/context_save.S

From 99bd8d39bf20d113dbb17b32837e134d64e65eec Mon Sep 17 00:00:00 2001
From: Diego Ferrari <services@diferrari.com>
Date: Sun, 28 Sep 2025 00:00:00 +0000
Subject: [PATCH 5/8] [CONT_SWITCH] unmapping x1,2,3,29,30, unmasking status
 bits

---
 kernel/process/context_save.S   | 6 ------
 kernel/process/context_switch.S | 4 ----
 kernel/process/process.h        | 6 +++---
 3 files changed, 3 insertions(+), 13 deletions(-)

diff --git a/kernel/process/context_save.S b/kernel/process/context_save.S
index cd73d8a9..48ff9ce9 100644
--- a/kernel/process/context_save.S
+++ b/kernel/process/context_save.S
@@ -21,11 +21,6 @@ msr daifset, #2
 
 3:
     mov x15, x0
-    mov x14, x1
-    mov x9, x2
-    mov x16, x3
-    mov x13, x29
-    mov x12, x30
     
 ldr x0, =cpec
 ldr x0, [x0]
@@ -50,7 +45,6 @@ stp x29, x30, [x0, #(8 * 28)]
 str x11, [x0, #(8 * 31)]
 
 //Status bits
-and x10, x10, 0xFFF
 str x10, [x0, #(8 * 33)]
 
 .endm
\ No newline at end of file
diff --git a/kernel/process/context_switch.S b/kernel/process/context_switch.S
index 8e21879a..d8d965fd 100644
--- a/kernel/process/context_switch.S
+++ b/kernel/process/context_switch.S
@@ -50,9 +50,5 @@ restore_context:
     msr elr_el1, x11
     
     mov x0, x15
-    mov x1, x14
-    mov x30, x12
-    mov x2, x9
-    mov x3, x16
 
     eret
\ No newline at end of file
diff --git a/kernel/process/process.h b/kernel/process/process.h
index 28d964fb..ff8da5cd 100644
--- a/kernel/process/process.h
+++ b/kernel/process/process.h
@@ -63,9 +63,9 @@ typedef struct {
 
 //Helper functions for accessing registers mapped to scratch regs
 #define PROC_X0 regs[14]
-#define PROC_X1 regs[13]
-#define PROC_X2 regs[8]
-#define PROC_X3 regs[15]
+#define PROC_X1 regs[0]
+#define PROC_X2 regs[1]
+#define PROC_X3 regs[2]
 #define PROC_X4 regs[3]
 // #define PROC_FP regs[12]
 // #define PROC_LR regs[11]

From db98117635e4994f7766f8111c5cfa26073d5311 Mon Sep 17 00:00:00 2001
From: Diego Ferrari <services@diferrari.com>
Date: Sun, 28 Sep 2025 00:00:00 +0000
Subject: [PATCH 6/8] [CONT_SWITCH] restore matching save

---
 kernel/process/context_save.S | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/process/context_save.S b/kernel/process/context_save.S
index 48ff9ce9..c5c579cd 100644
--- a/kernel/process/context_save.S
+++ b/kernel/process/context_save.S
@@ -11,10 +11,10 @@ msr daifset, #2
 
     b       3f
 
-1:  mov     x11, sp
+1:  mov     x16, sp
     b       3f
 
-2:  mrs     x11, sp_el0
+2:  mrs     x16, sp_el0
     ldr x18, =ksp
     //TODO: in order to ensure we don't ovewrite any stack data, save it to its own global variable
     mov sp, x18
@@ -42,7 +42,7 @@ stp x27, x28, [x0, #(8 * 26)]
 stp x29, x30, [x0, #(8 * 28)]
 
 // SP
-str x11, [x0, #(8 * 31)]
+str x16, [x0, #(8 * 31)]
 
 //Status bits
 str x10, [x0, #(8 * 33)]

From 63059e6dee4f4522aa0d4a915b2b9c905da770f9 Mon Sep 17 00:00:00 2001
From: Diego Ferrari <services@diferrari.com>
Date: Sun, 28 Sep 2025 00:00:00 +0000
Subject: [PATCH 7/8] [CONT_SWITCH] only overwriting x17, x18

---
 kernel/process/context_save.S   | 51 ++++++++++++------------
 kernel/process/context_switch.S | 69 +++++++++++++++++----------------
 kernel/process/process.h        | 10 ++---
 3 files changed, 67 insertions(+), 63 deletions(-)

diff --git a/kernel/process/context_save.S b/kernel/process/context_save.S
index c5c579cd..53338073 100644
--- a/kernel/process/context_save.S
+++ b/kernel/process/context_save.S
@@ -1,7 +1,7 @@
 .macro save_ctx
 msr daifset, #2
-    mrs     x10, spsr_el1
-    lsr     x18, x10, #2
+    mrs     x18, spsr_el1
+    lsr     x18, x18, #2
     and     x18, x18, #0b11
 
     cmp     x18, #1
@@ -11,40 +11,41 @@ msr daifset, #2
 
     b       3f
 
-1:  mov     x16, sp
+1:  mov     x17, sp
     b       3f
 
-2:  mrs     x16, sp_el0
+2:  mrs     x17, sp_el0
     ldr x18, =ksp
     //TODO: in order to ensure we don't ovewrite any stack data, save it to its own global variable
     mov sp, x18
 
 3:
-    mov x15, x0
     
-ldr x0, =cpec
-ldr x0, [x0]
-// Save general-purpose registers x1-x30 (excluding x0 which holds the pointer)
-stp x1, x2, [x0, #(8 * 0)]
-stp x3, x4, [x0, #(8 * 2)]
-stp x5, x6, [x0, #(8 * 4)]
-stp x7, x8, [x0, #(8 * 6)]
-stp x9, x10, [x0, #(8 * 8)]
-stp x11, x12, [x0, #(8 * 10)]
-stp x13, x14, [x0, #(8 * 12)]
-stp x15, x16, [x0, #(8 * 14)]
-stp x17, x18, [x0, #(8 * 16)]
-stp x19, x20, [x0, #(8 * 18)]
-stp x21, x22, [x0, #(8 * 20)]
-stp x23, x24, [x0, #(8 * 22)]
-stp x25, x26, [x0, #(8 * 24)]
-stp x27, x28, [x0, #(8 * 26)]
-stp x29, x30, [x0, #(8 * 28)]
+ldr x18, =cpec
+ldr x18, [x18]
+// Save general-purpose registers x1-x30
+stp x0, x1, [x18, #(8 * 0)]
+stp x2, x3, [x18, #(8 * 2)]
+stp x4, x5, [x18, #(8 * 4)]
+stp x6, x7, [x18, #(8 * 6)]
+stp x8, x9, [x18, #(8 * 8)]
+stp x10, x11, [x18, #(8 * 10)]
+stp x12, x13, [x18, #(8 * 12)]
+stp x14, x15, [x18, #(8 * 14)]
+str x16,      [x18, #(8 * 16)]
+str      x19, [x18, #(8 * 19)]
+stp x20, x21, [x18, #(8 * 20)]
+stp x22, x23, [x18, #(8 * 22)]
+stp x24, x25, [x18, #(8 * 24)]
+stp x26, x27, [x18, #(8 * 26)]
+stp x28, x29, [x18, #(8 * 28)]
+str x30,      [x18,#(8 * 30)] 
 
 // SP
-str x16, [x0, #(8 * 31)]
+str x17, [x18, #(8 * 31)]
 
 //Status bits
-str x10, [x0, #(8 * 33)]
+mrs x17, spsr_el1
+str x17, [x18, #(8 * 33)]
 
 .endm
\ No newline at end of file
diff --git a/kernel/process/context_switch.S b/kernel/process/context_switch.S
index d8d965fd..39eaa0d6 100644
--- a/kernel/process/context_switch.S
+++ b/kernel/process/context_switch.S
@@ -7,48 +7,51 @@ save_pc_interrupt:
 
 .global restore_context
 restore_context:
-    ldr x0, =cpec
-    ldr x0, [x0]
+    ldr x18, =cpec
+    ldr x18, [x18]
     // Restore general-purpose registers
-    ldp x1, x2, [x0, #(8 * 0)]
-    ldp x3, x4, [x0, #(8 * 2)]
-    ldp x5, x6, [x0, #(8 * 4)]
-    ldp x7, x8, [x0, #(8 * 6)]
-    ldp x9, x10, [x0, #(8 * 8)]
-    ldp x11, x12, [x0, #(8 * 10)]
-    ldp x13, x14, [x0, #(8 * 12)]
-    ldp x15, x16, [x0, #(8 * 14)]
-    ldp x17, x18, [x0, #(8 * 16)]
-    ldp x19, x20, [x0, #(8 * 18)]
-    ldp x21, x22, [x0, #(8 * 20)]
-    ldp x23, x24, [x0, #(8 * 22)]
-    ldp x25, x26, [x0, #(8 * 24)]
-    ldp x27, x28, [x0, #(8 * 26)]
-    ldp x29, x30, [x0, #(8 * 28)]    
-
-    ldr x11, [x0, #(8 * 31)]
-    ldr x10, [x0, #(8 * 33)]
-    msr spsr_el1, x10
-    lsr     x18, x10, #2
-    and     x18, x18, #0b11
-
-    cmp     x18, #1
+    ldp x0, x1, [x18, #(8 * 0)]
+    ldp x2, x3, [x18, #(8 * 2)]
+    ldp x4, x5, [x18, #(8 * 4)]
+    ldp x6, x7, [x18, #(8 * 6)]
+    ldp x8, x9, [x18, #(8 * 8)]
+    ldp x10, x11, [x18, #(8 * 10)]
+    ldp x12, x13, [x18, #(8 * 12)]
+    ldp x14, x15, [x18, #(8 * 14)]
+    ldr x16,      [x18, #(8 * 16)]
+    ldr      x19, [x18, #(8 * 19)]
+    ldp x20, x21, [x18, #(8 * 20)]
+    ldp x22, x23, [x18, #(8 * 22)]
+    ldp x24, x25, [x18, #(8 * 24)]
+    ldp x26, x27, [x18, #(8 * 26)]
+    ldp x28, x29, [x18, #(8 * 28)]
+    ldr x30,      [x18, #(8 * 30)]    
+
+    ldr x17, [x18, #(8 * 33)]
+    msr spsr_el1, x17
+    lsr     x17, x17, #2
+    and     x17, x17, #0b11
+
+    cmp     x17, #1
     b.eq    1f
-    cmp     x18, #0
+    cmp     x17, #0
     b.eq    2f
 
     b       3f
 
-1:  mov     sp, x11
+1:  ldr x17, [x18, #(8 * 31)]
+    mov     sp, x17
     b       3f
 
-2:  msr     sp_el0, x11
+2:  ldr x17, [x18, #(8 * 31)]
+    msr     sp_el0, x17
 
 3:
-    mov x29, x11
-    ldr x11, [x0, #(8 * 32)]
-    msr elr_el1, x11
-    
-    mov x0, x15
+    mov x29, x17
+    ldr x17, [x18, #(8 * 32)]
+    msr elr_el1, x17
+
+    mov x17, #0
+    mov x18, #0
 
     eret
\ No newline at end of file
diff --git a/kernel/process/process.h b/kernel/process/process.h
index ff8da5cd..1ce05785 100644
--- a/kernel/process/process.h
+++ b/kernel/process/process.h
@@ -62,11 +62,11 @@ typedef struct {
 } process_t;
 
 //Helper functions for accessing registers mapped to scratch regs
-#define PROC_X0 regs[14]
-#define PROC_X1 regs[0]
-#define PROC_X2 regs[1]
-#define PROC_X3 regs[2]
-#define PROC_X4 regs[3]
+#define PROC_X0 regs[0]
+#define PROC_X1 regs[1]
+#define PROC_X2 regs[2]
+#define PROC_X3 regs[3]
+#define PROC_X4 regs[4]
 // #define PROC_FP regs[12]
 // #define PROC_LR regs[11]
 // #define PROC_SP regs[10]

From 987dcf2724ae0785142dd1ddfcea8b2db9d8bf09 Mon Sep 17 00:00:00 2001
From: dif <git@diferrari.com>
Date: Sun, 28 Sep 2025 00:00:00 +0000
Subject: [PATCH 8/8] [CI] including fs

---
 .github/workflows/build.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 08abd0dc..466cbe5e 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -60,4 +60,4 @@ jobs:
             shared/libshared.a
             shared/*.h
             shared/**/*.h
-            fs/redos/user/*.elf
\ No newline at end of file
+            fs/*
\ No newline at end of file