Disable interrupts first and then set spinlock_count to 1.

Otherwise interrupt can be generated just after setting spinlock_count
and before disabling interrupts.

Sponsored by:	DARPA, AFRL

1 files changed, 3 insertions, 1 deletions

diff --git a/sys/riscv/riscv/machdep.c b/sys/riscv/riscv/machdep.c
index ae4c040dc479..417373744aeb 100644
--- a/sys/riscv/riscv/machdep.c
+++ b/sys/riscv/riscv/machdep.c
@@ -457,11 +457,13 @@ void
 spinlock_enter(void)
 {
 	struct thread *td;
+	register_t reg;
 
 	td = curthread;
 	if (td->td_md.md_spinlock_count == 0) {
+		reg = intr_disable();
 		td->td_md.md_spinlock_count = 1;
-		td->td_md.md_saved_sstatus_ie = intr_disable();
+		td->td_md.md_saved_sstatus_ie = reg;
 	} else
 		td->td_md.md_spinlock_count++;
 	critical_enter();