Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752449AbdLLLjm (ORCPT ); Tue, 12 Dec 2017 06:39:42 -0500 Received: from ozlabs.org ([103.22.144.67]:35835 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752298AbdLLLj2 (ORCPT ); Tue, 12 Dec 2017 06:39:28 -0500 X-powerpc-patch-notification: thanks X-powerpc-patch-commit: b9eab08d012fa093947b230f9a87257c27fb829b In-Reply-To: <20171116174537.duz4x6vfzhp44lfh@treble> To: Josh Poimboeuf , "Naveen N. Rao" From: Michael Ellerman Cc: linux-kernel@vger.kernel.org, Kamalesh Babulal , live-patching@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [v4.2] powerpc/modules: Don't try to restore r2 after a sibling call Message-Id: <3ywyXY71NTz9t3m@ozlabs.org> Date: Tue, 12 Dec 2017 22:39:25 +1100 (AEDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1006 Lines: 28 On Thu, 2017-11-16 at 17:45:37 UTC, Josh Poimboeuf wrote: > > From: Josh Poimboeuf > Subject: [PATCH v4.2] powerpc/modules: Don't try to restore r2 after a sibling call > > When attempting to load a livepatch module, I got the following error: > > module_64: patch_module: Expect noop after relocate, got 3c820000 > > The error was triggered by the following code in > unregister_netdevice_queue(): > > 14c: 00 00 00 48 b 14c > 14c: R_PPC64_REL24 net_set_todo > 150: 00 00 82 3c addis r4,r2,0 > > GCC didn't insert a nop after the branch to net_set_todo() because it's > a sibling call, so it never returns. The nop isn't needed after the > branch in that case. > > Signed-off-by: Josh Poimboeuf > Acked-by: Naveen N. Rao Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/b9eab08d012fa093947b230f9a8725 cheers