From: =?UTF-8?Q?Stefan_M=c3=a4tje?= <Stefan.Maetje@esd.eu>
Subject: Change of set_fs() in uaccess.h breaks this header being self
 contained for x86 (4.14-rc1)
To: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Message-ID: <ca709cb0-7151-cceb-be60-1a8ceccca259@esd.eu>
Date: Mon, 18 Sep 2017 20:32:19 +0200
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Hi,

there is a change in Linus' mainline kernel
(https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/arch/x86/include/asm/uaccess.h?id=6c51e67b64d169419fb13318035bb442f9176612)
that changes the set_fs() macro into an inline function.

This breaks the build of an out of kernel driver I maintain with this
message:

./arch/x86/include/asm/uaccess.h: In function ‘set_fs’:
./arch/x86/include/asm/uaccess.h:31:9: error: dereferencing pointer to
incomplete type

set_fs() is referencing the "current" pointer which is of type "struct
task_struct" declared in include/linux/sched.h.

Before the change set_fs() was a macro. Because I don't use it it was of
no concern for me. But now the compiler needs to compile the inline
function set_fs() and fails.

Should I add the needed <linux/sched.h> myself in my code or will that
be changed / fixed in the <asm/uaccess.h> header by including the
missing header.

Thanks for any advice.

Best regards,
	Stefan Mätje