From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CFB3D7F for ; Fri, 19 Apr 2024 00:22:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713486150; cv=none; b=ripxU6C3dzXO1os76UaYJMJpyhCRPRy9yv9bD+YOWdNH+BeXkcITZJiiISH/fXGtMgTIOBT+HBTYcF4FMtoqwSR/Nqaq7XBTx9aBTah+7IW0wwP5IrO8ybFwT4k2HCBUwVzISwLKeuN+YqAtBrEGajf2LFWF8Sv0AIuqVEEBHms= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713486150; c=relaxed/simple; bh=d3bTP7KKC9aZn1EnXjEovuY7nPSOZbnGxThq3FCimdk=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition; b=pyFJ3/ZPPQbWCqm9LgYgbsu1RqoW2bvYF6r6YTG0wMco+Rf1fnLDFPZ3vK83tNoFnySuKmHWQ0bmbzzZKxKhKGU7rYw7DZuOu/HOSDiDCYnCl9rjKt3XxSpM0wIbTkMokOQdtoHkUJWGmGArGlIPuIhp0FZv5RensCjuUZXhBdE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gj2pshnT; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gj2pshnT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 06F73C113CC; Fri, 19 Apr 2024 00:22:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1713486150; bh=d3bTP7KKC9aZn1EnXjEovuY7nPSOZbnGxThq3FCimdk=; h=Date:From:To:Cc:Subject:Reply-To:From; b=gj2pshnT+qP2eCmnwAdg4gUaP2cuYyRadXdsNjVJmXdzPvkSS1WZzBe8U1ZEkP8eb 23YUmpEgyCjE5VwFYNPDTpfI4S+s/iAW1liHs5wKdGg67IP2TfFo2hbqCIyXC5vw7Z Y3A4Ums9Bnitb8xBIWYtv84qRpkB+NWSzO2Cyat8YASWbFM0Ond22nEKiGawiJ3eLL QAYVXpnXBiKvbKDtNEbBog1cctm6eYTMSLFQHY2FCOvYA0EY762PYxsNgp3RCWicgW iXqNE80JCNJu/SB+WdPtLP5AhhNHQPpclMgxyvnOzFHeP9skOjGtqDjj4JGErjn3PZ 85GZarQsMbkyA== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id F39F6CE0444; Thu, 18 Apr 2024 17:22:26 -0700 (PDT) Date: Thu, 18 Apr 2024 17:22:26 -0700 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: Linus Torvalds , Daniel Sneddon , Thomas Gleixner , Josh Poimboeuf , Stephen Rothwell Subject: [BUG] objtool complains about missing __noreturn__ on x64_sys_call() and ia32_sys_call() Message-ID: <6dba9b32-db2c-4e6d-9500-7a08852f17a3@paulmck-laptop> Reply-To: paulmck@kernel.org Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hello! Recent -next kernels, including next-20240418, get the following objtool build errors: vmlinux.o: warning: objtool: x64_sys_call+0x2804: __x64_sys_exit() is missing a __noreturn annotation vmlinux.o: warning: objtool: ia32_sys_call+0x29b6: __ia32_sys_exit_group() is missing a __noreturn annotation These functions appear to have been added to -next and mainline by commit 1e3ad78334a6 ("x86/syscall: Don't force use of indirect calls for system calls"). But the diagnostic does not make much sense because both functions always return unless the system call itself doesn't return. Adding annotate_unreachable() to the end of each function did not help, header comment notwithstanding. On the other hand, these objtool errors were from Ubuntu clang version 14.0.0-1ubuntu1.1 rather than GCC. I also freely confess that I don't understand the "};" at the end of both functions. Thoughts? Thanx, Paul