From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sodagudi Prasad Subject: opaque types instead of union epoll_data Date: Tue, 07 Mar 2017 04:31:19 -0800 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Return-path: Sender: linux-kernel-owner@vger.kernel.org To: linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Cc: gregkh@linuxfoundation.org List-Id: linux-api@vger.kernel.org Hi All, uapi structs epoll_data are more opaque than user space expects. kernel have defined as __u64 instead of the union epoll_data. Because of this libc have redefined struct epoll_event with union data member. https://android.googlesource.com/platform/bionic.git/+/master/libc/include/sys/epoll.h typedef union epoll_data { void* ptr; int fd; uint32_t u32; uint64_t u64; } epoll_data_t; struct epoll_event { uint32_t events; epoll_data_t data; } Kernel UAPI header defined as "include/uapi/linux/eventpoll.h" struct epoll_event { __u32 events; __u64 data; =====>opaque type instead of union epoll_data } EPOLL_PACKED; Because of this we are landing into some issues as we copy kernel headers. Will it be going to be addressed? -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, Linux Foundation Collaborative Project