Hello,
Maximus Minter, le mar. 07 avril 2026 22:30:33 -0400, a ecrit:
> - Protect all_eventcounters array with a lock
> diff --git a/kern/eventcount.c b/kern/eventcount.c
> index 70b9f0d5..8f786846 100644
> --- a/kern/eventcount.c
> +++ b/kern/eventcount.c
> @@ -55,6 +55,10 @@
>
> #define MAX_EVCS 10 /* xxx for now */
> evc_t all_eventcounters[MAX_EVCS];
> +static decl_simple_lock_data(, all_evc_lock);
> +
> +#define evc_array_lock() simple_lock(&all_evc_lock)
> +#define evc_array_unlock() simple_unlock(&all_evc_lock)
See evc_signal mentioned to be called from interrupt context, so we need
to use splsched()/splx() when taking it.
> @@ -139,13 +151,18 @@ kern_return_t evc_wait(natural_t ev_id)
> kern_return_t ret;
> evc_t ev;
>
> + evc_array_lock();
> if ((ev_id >= MAX_EVCS) ||
> ((ev = all_eventcounters[ev_id]) == 0) ||
> (ev->ev_id != ev_id) || (ev->sanity != ev))
> + {
> + evc_array_unlock();
> return KERN_INVALID_ARGUMENT;
> + }
> + simple_lock(&ev->lock);
> + evc_array_unlock();
>
> s = splsched();
> - simple_lock(&ev->lock);
> /*
> * The values assumed by the "count" field are
> * as follows:
> @@ -166,8 +183,8 @@ kern_return_t evc_wait(natural_t ev_id)
> ev->count--;
> ev->waiting_thread = current_thread();
> assert_wait((event_t) 0, TRUE); /* ifnot race */
> - simple_unlock(&ev->lock);
?? why removing the unlock?
> @@ -212,7 +233,6 @@ kern_return_t evc_wait_clear(natural_t ev_id)
> ev->count = -1;
> ev->waiting_thread = current_thread();
> assert_wait((event_t) 0, TRUE); /* ifnot race */
> - simple_unlock(&ev->lock);
ditto
> thread_block(evc_continue);
> /* NOTREACHED */
> }
Samuel
