diff --git a/libs/pika/coroutines/include/pika/coroutines/detail/posix_utility.hpp b/libs/pika/coroutines/include/pika/coroutines/detail/posix_utility.hpp
index aba1863d..bdbddd2f 100644
--- a/libs/pika/coroutines/include/pika/coroutines/detail/posix_utility.hpp
+++ b/libs/pika/coroutines/include/pika/coroutines/detail/posix_utility.hpp
@@ -80,7 +80,7 @@ namespace pika { namespace threads { namespace coroutines { namespace detail {
         inline void* alloc_stack(std::size_t size)
         {
             void* real_stack = ::mmap(nullptr, size + EXEC_PAGESIZE,
-                PROT_EXEC | PROT_READ | PROT_WRITE,
+                PROT_READ | PROT_WRITE,
 #if defined(__APPLE__)
                 MAP_PRIVATE | MAP_ANON | MAP_NORESERVE,
 #elif defined(__FreeBSD__)