From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DB62FC433DF for ; Thu, 28 May 2020 00:31:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AD0FB20888 for ; Thu, 28 May 2020 00:31:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590625885; bh=chuSr3FoCBRQngQ6m8+G1nqucLsORSNtGxzZXnM/qHo=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=laObBMVLorjjXgM5hrWp0rTZkyVloVHjbyGSQfdSjk8UKnDn3PGhdm9s/jwuV4X0w mSR3326WAXujL9KvmOhRLY0Itxugp1JkZBEvRxB7q8Db57x4lg7yiqJzFwJ/0u5m/e 7xZMxHerWGe3GaNepvrRYy1csQjqzh1f80hgHrWM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725922AbgE1AbY (ORCPT ); Wed, 27 May 2020 20:31:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:56234 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725267AbgE1AbY (ORCPT ); Wed, 27 May 2020 20:31:24 -0400 Received: from devnote2 (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CEED4207CB; Thu, 28 May 2020 00:31:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590625884; bh=chuSr3FoCBRQngQ6m8+G1nqucLsORSNtGxzZXnM/qHo=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=k38BlaGnj/bNSVWELhnzWpEXGSXVkELh6GkXp/X8oFNGz9TmO5GfZiEGCYgIcQQ+T Jk+srUGzakC3OfUU6hj6zwVWYIO+Z+jUzCQ9kmo/0ClgaHAgl8IeFd3k7ZObx2/h6u +miY1tc01t7h51Pmn+eFKE7T+4MUqWAmQ6A811C0= Date: Thu, 28 May 2020 09:31:17 +0900 From: Masami Hiramatsu To: Peter Zijlstra Cc: Adrian Hunter , Arnaldo Carvalho de Melo , Ingo Molnar , Masami Hiramatsu , Steven Rostedt , Borislav Petkov , "H . Peter Anvin" , x86@kernel.org, Mark Rutland , Alexander Shishkin , Mathieu Poirier , Leo Yan , Jiri Olsa , linux-kernel@vger.kernel.org Subject: Re: [PATCH V7 03/15] kprobes: Add symbols for kprobe insn pages Message-Id: <20200528093117.181bf843a2f8f2c39fcf9860@kernel.org> In-Reply-To: <20200527174345.GB706478@hirez.programming.kicks-ass.net> References: <20200512121922.8997-1-adrian.hunter@intel.com> <20200512121922.8997-4-adrian.hunter@intel.com> <20200527174345.GB706478@hirez.programming.kicks-ass.net> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 27 May 2020 19:43:45 +0200 Peter Zijlstra wrote: > On Tue, May 12, 2020 at 03:19:10PM +0300, Adrian Hunter wrote: > > @@ -2179,6 +2181,49 @@ int kprobe_add_area_blacklist(unsigned long start, unsigned long end) > > return 0; > > } > > > > +int kprobe_cache_get_kallsym(struct kprobe_insn_cache *c, unsigned int *symnum, > > + unsigned long *value, char *type, char *sym) > > +{ > > + struct kprobe_insn_page *kip; > > + int ret = -ERANGE; > > + > > + rcu_read_lock(); > > + list_for_each_entry_rcu(kip, &c->pages, list) { > > + if ((*symnum)--) > > + continue; > > + strlcpy(sym, c->sym, KSYM_NAME_LEN); > > + *type = 't'; > > + *value = (unsigned long)kip->insns; > > + ret = 0; > > + break; > > + } > > + rcu_read_unlock(); > > + > > + return ret; > > +} > > This fails on sparc64-defconfig. > > In file included from ../include/linux/kprobes.h:19:0, > from ../kernel/kprobes.c:21: > ../kernel/kprobes.c: In function 'kprobe_cache_get_kallsym': > ../include/linux/rculist.h:382:49: error: dereferencing pointer to incomplete type 'struct kprobe_insn_page' > > Please provide a new patch. Ah, yes. Since some archs doesn't require special out-of-line trampoline, we need to check __ARCH_WANT_KPROBES_INSN_SLOT, and if not, kprobe_cache_get_kallsym() has do nothing and return -ERANGE. Thank you, -- Masami Hiramatsu