From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: UAPI headers including non-UAPI headers by accident? Date: Thu, 18 Jun 2015 09:58:52 +0200 Message-ID: <9141492.JqTlmk9dHk@wuerfel> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Cc: Andy Lutomirski , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Linux API , David Woodhouse List-Id: linux-api@vger.kernel.org On Thursday 18 June 2015 09:52:36 Michael Kerrisk wrote: > [CC += David] > > On 2 June 2015 at 18:36, Andy Lutomirski wrote: > > include/uapi/linux/signal.h starts with: > > > > #ifndef _UAPI_LINUX_SIGNAL_H > > #define _UAPI_LINUX_SIGNAL_H > > > > #include > > #include > > > > This causes it to include , which is not the same thing > > as . Changing that will break userspace use of > > this header, though, as the uapi/ won't get removed. > > > > What's the correct fix? This is causing trouble with a UML build for me. > > Perhaps David has some insight, since he architected the original UAPI split. The uapi headers are installed without the uapi prefix. This means that inside of the kernel, we get linux/signal.h -> uapi/linux/signal.h -> asm/signal.h -> uapi/asm/signal.h while in the installed headers we just get linux/signal.h -> asm/signal.h This all looks right to me: user space only sees the exported portions under the traditional names, while the kernel sees both the kernel-side and user-side definitions from the same path. Arnd