From 0972694abb1fe2137eeed3c0bdfa70eb31327c8f Mon Sep 17 00:00:00 2001 From: Ian Moffett Date: Wed, 20 Aug 2025 00:50:36 -0400 Subject: kernel: Disable preemption on spinlock_acquire() To prevent priority inversion by disabling task preemption upon spinlock acquisition and reenabling upon release Signed-off-by: Ian Moffett --- sys/kern/kern_synch.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'sys/kern/kern_synch.c') diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c index 2ac39c8..3fe6047 100644 --- a/sys/kern/kern_synch.c +++ b/sys/kern/kern_synch.c @@ -84,6 +84,7 @@ spinlock_usleep(struct spinlock *lock, size_t usec_max) void spinlock_acquire(struct spinlock *lock) { + sched_preempt_set(false); while (__atomic_test_and_set(&lock->lock, __ATOMIC_ACQUIRE)) { md_pause(); } @@ -117,6 +118,7 @@ void spinlock_release(struct spinlock *lock) { __atomic_clear(&lock->lock, __ATOMIC_RELEASE); + sched_preempt_set(true); } /* -- cgit v1.2.3