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=-14.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 2DF18C433DF for ; Thu, 27 Aug 2020 11:52:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EA7332177B for ; Thu, 27 Aug 2020 11:52:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598529173; bh=NDgTujQf40aEc0EizGnGw4M8AkJqzxUV0D0lyCYMSxE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tsaBOEe+WndOIc9+yHu+WAu+U97B5Vyi76AQosrdCpAum/GIiDPLuNfDrunLBVRtk ePnP39taUOld6rN9k89xrthwfxI7wQyQ0bsKatS9LClpKyZqvGVgsWknuGaZUCvWpq oawhWQvSU/6gppSmWM8QaF2E9rg6NE5lHn9CewqA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728862AbgH0Lwt (ORCPT ); Thu, 27 Aug 2020 07:52:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:50496 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728442AbgH0LhW (ORCPT ); Thu, 27 Aug 2020 07:37:22 -0400 Received: from localhost.localdomain (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2937C22CE3; Thu, 27 Aug 2020 11:37:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598528242; bh=NDgTujQf40aEc0EizGnGw4M8AkJqzxUV0D0lyCYMSxE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zDxBjmB9/hfE+R0yjcK7NOkiEODqZz+6nBCgB/Cm3P/JNWnzoiAiI+TdwpWw/QAGb MTejx0M9iJZj5zMasNNgFt5T4fwDl2H/1XSDXFyCXZX18lgP9IKFuJpjVgVxJyv1os iQlhVAGiLM/HM6E94Je6FS6aGK+dk3dnIBTF6EQg= From: Masami Hiramatsu To: linux-kernel@vger.kernel.org, Peter Zijlstra Cc: Eddy Wu , x86@kernel.org, "David S . Miller" , Steven Rostedt , Ingo Molnar , "Naveen N . Rao" , Anil S Keshavamurthy , linux-arch@vger.kernel.org Subject: [PATCH v2 12/15] sh: kprobes: Use generic kretprobe trampoline handler Date: Thu, 27 Aug 2020 20:37:18 +0900 Message-Id: <159852823801.707944.8834191320512248625.stgit@devnote2> X-Mailer: git-send-email 2.25.1 In-Reply-To: <159852811819.707944.12798182250041968537.stgit@devnote2> References: <159852811819.707944.12798182250041968537.stgit@devnote2> User-Agent: StGit/0.19 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Signed-off-by: Masami Hiramatsu --- arch/sh/kernel/kprobes.c | 59 +++------------------------------------------- 1 file changed, 4 insertions(+), 55 deletions(-) diff --git a/arch/sh/kernel/kprobes.c b/arch/sh/kernel/kprobes.c index 318296f48f1a..118927ab63af 100644 --- a/arch/sh/kernel/kprobes.c +++ b/arch/sh/kernel/kprobes.c @@ -204,6 +204,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs) { ri->ret_addr = (kprobe_opcode_t *) regs->pr; + ri->fp = NULL; /* Replace the return addr with trampoline addr */ regs->pr = (unsigned long)kretprobe_trampoline; @@ -302,62 +303,10 @@ static void __used kretprobe_trampoline_holder(void) */ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) { - struct kretprobe_instance *ri = NULL; - struct hlist_head *head, empty_rp; - struct hlist_node *tmp; - unsigned long flags, orig_ret_address = 0; - unsigned long trampoline_address = (unsigned long)&kretprobe_trampoline; + regs->pc = __kretprobe_trampoline_handler(regs, + (unsigned long)&kretprobe_trampoline, NULL); - INIT_HLIST_HEAD(&empty_rp); - kretprobe_hash_lock(current, &head, &flags); - - /* - * It is possible to have multiple instances associated with a given - * task either because an multiple functions in the call path - * have a return probe installed on them, and/or more then one return - * return probe was registered for a target function. - * - * We can handle this because: - * - instances are always inserted at the head of the list - * - when multiple return probes are registered for the same - * function, the first instance's ret_addr will point to the - * real return address, and all the rest will point to - * kretprobe_trampoline - */ - hlist_for_each_entry_safe(ri, tmp, head, hlist) { - if (ri->task != current) - /* another task is sharing our hash bucket */ - continue; - - if (ri->rp && ri->rp->handler) { - __this_cpu_write(current_kprobe, &ri->rp->kp); - ri->rp->handler(ri, regs); - __this_cpu_write(current_kprobe, NULL); - } - - orig_ret_address = (unsigned long)ri->ret_addr; - recycle_rp_inst(ri, &empty_rp); - - if (orig_ret_address != trampoline_address) - /* - * This is the real return address. Any other - * instances associated with this task are for - * other calls deeper on the call stack - */ - break; - } - - kretprobe_assert(ri, orig_ret_address, trampoline_address); - - regs->pc = orig_ret_address; - kretprobe_hash_unlock(current, &flags); - - hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) { - hlist_del(&ri->hlist); - kfree(ri); - } - - return orig_ret_address; + return 1; } static int __kprobes post_kprobe_handler(struct pt_regs *regs)