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 47937C433E2 for ; Fri, 28 Aug 2020 12:29:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0B5FB20872 for ; Fri, 28 Aug 2020 12:29:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598617761; bh=GT7QIE1OL2IEp8IqUl23H8/1NDehpfu08ti38E+0+vw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Ked6IdJeh2WaehUfVtPUPTaRkKZHavj9RmuRXqXzClsZdtM+I9C+FQq/iOi1gabqF AyrOC7x7BOrsqULQ062J3GLomW6Ntp5HNNPmUaIl3GbPUdU7i23JCRKFnQB8uhlYdj 7XqzWiq2u9Pj2z+cwLPgjK/rfgI3tfN9V0sfkxCs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729377AbgH1M2x (ORCPT ); Fri, 28 Aug 2020 08:28:53 -0400 Received: from mail.kernel.org ([198.145.29.99]:39574 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729318AbgH1M1j (ORCPT ); Fri, 28 Aug 2020 08:27:39 -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 5661F20848; Fri, 28 Aug 2020 12:27:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598617658; bh=GT7QIE1OL2IEp8IqUl23H8/1NDehpfu08ti38E+0+vw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BTBRnimp4uucoP/uXWXz8bJzzgj3I8j8+333ejemdjx4hv/1WSZra/BMFDmxEmGUl Am4iXdqbm+E6oo2S7w6EUnpJyFL8MpsINUm/F+CJYZmmJDuk78hDXxsJ6/ZftDwiGd KQ8gOiYXa5HqG4X6XHulWqgiHNI2YbOsTINlGP54= From: Masami Hiramatsu To: linux-kernel@vger.kernel.org, Peter Zijlstra Cc: Eddy_Wu@trendmicro.com, x86@kernel.org, davem@davemloft.net, rostedt@goodmis.org, naveen.n.rao@linux.ibm.com, anil.s.keshavamurthy@intel.com, linux-arch@vger.kernel.org, cameron@moodycamel.com, oleg@redhat.com, will@kernel.org, paulmck@kernel.org, mhiramat@kernel.org Subject: [PATCH v4 05/23] arc: kprobes: Use generic kretprobe trampoline handler Date: Fri, 28 Aug 2020 21:27:33 +0900 Message-Id: <159861765296.992023.2764312742056468660.stgit@devnote2> X-Mailer: git-send-email 2.25.1 In-Reply-To: <159861759775.992023.12553306821235086809.stgit@devnote2> References: <159861759775.992023.12553306821235086809.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/arc/kernel/kprobes.c | 54 ++------------------------------------------- 1 file changed, 2 insertions(+), 52 deletions(-) diff --git a/arch/arc/kernel/kprobes.c b/arch/arc/kernel/kprobes.c index 7d3efe83cba7..cabef45f11df 100644 --- a/arch/arc/kernel/kprobes.c +++ b/arch/arc/kernel/kprobes.c @@ -388,6 +388,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, { ri->ret_addr = (kprobe_opcode_t *) regs->blink; + ri->fp = NULL; /* Replace the return addr with trampoline addr */ regs->blink = (unsigned long)&kretprobe_trampoline; @@ -396,58 +397,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, static 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; - - 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 than 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) - ri->rp->handler(ri, regs); - - 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->ret = orig_ret_address; - - kretprobe_hash_unlock(current, &flags); - - hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) { - hlist_del(&ri->hlist); - kfree(ri); - } + regs->ret = __kretprobe_trampoline_handler(regs, &kretprobe_trampoline, NULL); /* By returning a non zero value, we are telling the kprobe handler * that we don't want the post_handler to run