Improvements

Author: bjoernQ

esp-hal/src/debugger.rs

@@ -28,7 +28,7 @@ pub fn debugger_connected() -> bool {
 ///
 /// Breakpoint 0 is used.
 ///
-/// # Safety:
+/// # Safety
 /// The address must be word aligned.
 pub unsafe fn set_stack_watchpoint(addr: usize) {
  assert!(addr.is_multiple_of(4));

esp-hal/src/exception_handler/mod.rs

@@ -25,20 +25,21 @@ pub(crate) fn breakpoint_interrupt(context: &TrapFrame) {
  );
  }
 
+ #[cfg(stack_guard_monitoring)]
  if dbgcause & 4 != 0 && dbgcause & 0b1111_0000_0000 == 0 {
  panic!(
  "\n\nDetected a write to the stack guard value on {:?}\n{:?}",
  crate::system::Cpu::current(),
  context
  );
- } else {
- panic!(
- "\n\nBreakpoint on {:?}\n{:?}\nDebug cause: {}",
- crate::system::Cpu::current(),
- context,
- dbgcause
- );
  }
+
+ panic!(
+ "\n\nBreakpoint on {:?}\n{:?}\nDebug cause: {}",
+ crate::system::Cpu::current(),
+ context,
+ dbgcause
+ );
 }
 
 #[cfg(riscv)]
@@ -52,42 +53,52 @@ unsafe extern "C" fn ExceptionHandler(context: &TrapFrame) -> ! {
  static mut __stack_chk_guard: u32;
  }
 
- let guard_addr = core::ptr::addr_of_mut!(__stack_chk_guard) as *mut _ as usize;
-
  if code == 14 {
  panic!(
  "Stack overflow detected at 0x{:x}, possibly called by 0x{:x}",
  mepc, context.ra
  );
- } else if code == 3 && mtval == guard_addr {
- panic!(
- "Detected a write to the stack guard value at 0x{:x}, possibly called by 0x{:x}",
- mepc, context.ra
- )
- } else {
- let code = match code {
- 0 => "Instruction address misaligned",
- 1 => "Instruction access fault",
- 2 => "Illegal instruction",
- 3 => "Breakpoint",
- 4 => "Load address misaligned",
- 5 => "Load access fault",
- 6 => "Store/AMO address misaligned",
- 7 => "Store/AMO access fault",
- 8 => "Environment call from U-mode",
- 9 => "Environment call from S-mode",
- 10 => "Reserved",
- 11 => "Environment call from M-mode",
- 12 => "Instruction page fault",
- 13 => "Load page fault",
- 14 => "Reserved",
- 15 => "Store/AMO page fault",
- _ => "UNKNOWN",
- };
+ }
 
- panic!(
- "Exception '{}' mepc=0x{:08x}, mtval=0x{:08x}\n{:?}",
- code, mepc, mtval, context
- );
+ #[cfg(stack_guard_monitoring)]
+ if code == 3 {
+ let guard_addr = core::ptr::addr_of_mut!(__stack_chk_guard) as *mut _ as usize;
+
+ if mtval == guard_addr {
+ panic!(
+ "Detected a write to the main stack's guard value at 0x{:x}, possibly called by 0x{:x}",
+ mepc, context.ra
+ )
+ } else {
+ panic!(
+ "Breakpoint exception at 0x{:08x}, mtval=0x{:08x}\n{:?}",
+ mepc, mtval, context
+ );
+ }
  }
+
+ let code = match code {
+ 0 => "Instruction address misaligned",
+ 1 => "Instruction access fault",
+ 2 => "Illegal instruction",
+ 3 => "Breakpoint",
+ 4 => "Load address misaligned",
+ 5 => "Load access fault",
+ 6 => "Store/AMO address misaligned",
+ 7 => "Store/AMO access fault",
+ 8 => "Environment call from U-mode",
+ 9 => "Environment call from S-mode",
+ 10 => "Reserved",
+ 11 => "Environment call from M-mode",
+ 12 => "Instruction page fault",
+ 13 => "Load page fault",
+ 14 => "Reserved",
+ 15 => "Store/AMO page fault",
+ _ => "UNKNOWN",
+ };
+
+ panic!(
+ "Exception '{}' mepc=0x{:08x}, mtval=0x{:08x}\n{:?}",
+ code, mepc, mtval, context
+ );
 }

esp-hal/src/soc/mod.rs

@@ -247,7 +247,7 @@ fn setup_stack_guard() {
  }
 }
 
-#[cfg(feature = "rt")]
+#[cfg(all(feature = "rt", stack_guard_monitoring))]
 pub(crate) fn enable_main_stack_guard_monitoring() {
  unsafe {
  unsafe extern "C" {