runtime/irq: use assembly for naked IRQ handler

and solves the bug introduced due to stack unwinding...
This commit is contained in:
pca006132 2021-01-18 16:43:49 +08:00
parent 9e8b554c6d
commit be01fbd943
2 changed files with 24 additions and 1 deletions

View File

@ -18,14 +18,36 @@ static CORE1_RESTART: AtomicBool = AtomicBool::new(false);
#[no_mangle]
#[naked]
pub unsafe extern "C" fn IRQ() {
asm!(
// setup SP, depending on CPU 0 or 1
"mrc p15, #0, r0, c0, c0, #5",
"movw r1, :lower16:__stack0_start",
"movt r1, :upper16:__stack0_start",
"tst r0, #3",
"movwne r1, :lower16:__stack1_start",
"movtne r1, :upper16:__stack1_start",
"mov sp, r1",
"bl __IRQ",
options(noreturn)
);
}
#[no_mangle]
pub unsafe extern "C" fn __IRQ() {
if MPIDR.read().cpu_id() == 1 {
let mpcore = mpcore::RegisterBlock::mpcore();
let mut gic = gic::InterruptController::gic(mpcore);
let id = gic.get_interrupt_id();
if id.0 == 0 {
gic.end_interrupt(id);
// save the SP and set it back after exiting IRQ
// exception unwinding expect to unwind from this function, as this is not the entrance
// function, maybe to IRQ which cannot further unwind...
// if we set the SP to __stack1_start, interesting exceptions would be triggered when
// we try to unwind the stack...
let v = SP.read();
asm::exit_irq();
SP.write(&mut __stack1_start as *mut _ as u32);
SP.write(v);
asm::enable_irq();
CORE1_RESTART.store(false, Ordering::Relaxed);
notify_spin_lock();

View File

@ -7,6 +7,7 @@
#![feature(const_btree_new)]
#![feature(const_in_array_repeat_expressions)]
#![feature(naked_functions)]
#![feature(asm)]
extern crate alloc;