Kernel: Switch process file descriptor table from spinlock to mutex

There's no reason for this to use a spinlock. Instead, let's allow
threads to block if someone else is using the descriptor table.

1 files changed, 1 insertions, 1 deletions

diff --git a/Kernel/Syscalls/dup2.cpp b/Kernel/Syscalls/dup2.cpp
index 74273b56f0..9ddf754934 100644
--- a/Kernel/Syscalls/dup2.cpp
+++ b/Kernel/Syscalls/dup2.cpp
@@ -13,7 +13,7 @@ ErrorOr<FlatPtr> Process::sys$dup2(int old_fd, int new_fd)
 {
     VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this);
     TRY(require_promise(Pledge::stdio));
-    return m_fds.with([&](auto& fds) -> ErrorOr<FlatPtr> {
+    return m_fds.with_exclusive([&](auto& fds) -> ErrorOr<FlatPtr> {
         auto description = TRY(fds.open_file_description(old_fd));
         if (old_fd == new_fd)
             return new_fd;