This is because ctx->io_ev_fd is rcu_dereference_protected using ctx->uring_lock in io_eventfd_unregister. Not locking the function resulted in suspicious RCU usage reported by kernel test robot. Reported-by: kernel test robot <oliver.sang(a)intel.com&gt; Signed-off-by: Usama Arif <usama.arif(a)bytedance.com&gt; --- fs/io_uring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index ad8f84376955..dbc9d3f3f6c5 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -9471,8 +9471,8 @@ static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx) __io_sqe_files_unregister(ctx); if (ctx->rings) __io_cqring_overflow_flush(ctx, true); - mutex_unlock(&ctx->uring_lock); io_eventfd_unregister(ctx); + mutex_unlock(&ctx->uring_lock); io_destroy_buffers(ctx); if (ctx->sq_creds) put_cred(ctx->sq_creds); -- 2.25.1