Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S979037AbdDXWtE (ORCPT ); Mon, 24 Apr 2017 18:49:04 -0400 Received: from ozlabs.org ([103.22.144.67]:34289 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S977717AbdDXWr2 (ORCPT ); Mon, 24 Apr 2017 18:47:28 -0400 X-powerpc-patch-notification: thanks X-powerpc-patch-commit: 290e3070762ac80e5fc4087d8c4de7e3f1d90aca In-Reply-To: <77e96021f60d0cebd75bb8c5968e179c32781016.1492604782.git.naveen.n.rao@linux.vnet.ibm.com> To: "Naveen N. Rao" , Ingo Molnar From: Michael Ellerman Cc: linuxppc-dev@lists.ozlabs.org, Masami Hiramatsu , linux-kernel@vger.kernel.org Subject: Re: [v3,2/7] powerpc: kprobes: fix handling of function offsets on ABIv2 Message-Id: <3wBhLQ2Vy4z9s8Y@ozlabs.org> Date: Tue, 25 Apr 2017 08:47:26 +1000 (AEST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1446 Lines: 36 On Wed, 2017-04-19 at 12:51:01 UTC, "Naveen N. Rao" wrote: > commit 239aeba76409 ("perf powerpc: Fix kprobe and kretprobe handling > with kallsyms on ppc64le") changed how we use the offset field in struct > kprobe on ABIv2. perf now offsets from the GEP (Global entry point) if an > offset is specified and otherwise chooses the LEP (Local entry point). > > Fix the same in kernel for kprobe API users. We do this by extending > kprobe_lookup_name() to accept an additional parameter to indicate the > offset specified with the kprobe registration. If offset is 0, we return > the local function entry and return the global entry point otherwise. > > With: > # cd /sys/kernel/debug/tracing/ > # echo "p _do_fork" >> kprobe_events > # echo "p _do_fork+0x10" >> kprobe_events > > before this patch: > # cat ../kprobes/list > c0000000000d0748 k _do_fork+0x8 [DISABLED] > c0000000000d0758 k _do_fork+0x18 [DISABLED] > c0000000000412b0 k kretprobe_trampoline+0x0 [OPTIMIZED] > > and after: > # cat ../kprobes/list > c0000000000d04c8 k _do_fork+0x8 [DISABLED] > c0000000000d04d0 k _do_fork+0x10 [DISABLED] > c0000000000412b0 k kretprobe_trampoline+0x0 [OPTIMIZED] > > Acked-by: Ananth N Mavinakayanahalli > Signed-off-by: Naveen N. Rao Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/290e3070762ac80e5fc4087d8c4de7 cheers