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=ham 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 30B0DC433E1 for ; Thu, 27 Aug 2020 15:17:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EEBBF2080C for ; Thu, 27 Aug 2020 15:17:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598541472; bh=L/e1Ny4hhfpRjK1FA5n+uilobQaA7dHkNtzT1eO2uMQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=HMTtMTx9QUlqwSfubnYguVeOaMEA2YNuful59ywiEV7Rtc9LfI3ZVJZlbl/WKwPEv eEOhgsU1oA0Zbv94Kzu6BDfGTp/W3ePA5zoZQYimklwID+ugJaw+vHhCd94kTiH4AV OhpBLC1klAkOMZ9j/ejobwbdIMvxJwisSIQAJbl4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728446AbgH0PRs (ORCPT ); Thu, 27 Aug 2020 11:17:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:50008 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728587AbgH0Lge (ORCPT ); Thu, 27 Aug 2020 07:36:34 -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 1BCAD20738; Thu, 27 Aug 2020 11:36:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598528193; bh=L/e1Ny4hhfpRjK1FA5n+uilobQaA7dHkNtzT1eO2uMQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Q+aDRXx8TfVAT7m5TmuN5n/02uCAIiqjyCuQJ2oMqSevPXmDX+Ga59ykbZL4v/xCt b74lZ63Iv++rBEepc3lNjuTfvskzrFxbxsUKH45Pag8eoAYSuRJuGM/4KmC7OYek2k xQ1+8VYWbn4oSFDZ/cSHQUyM3ovfp129Ww2BvVhw= 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 07/15] ia64: kprobes: Use generic kretprobe trampoline handler Date: Thu, 27 Aug 2020 20:36:28 +0900 Message-Id: <159852818798.707944.9249352111340231044.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/ia64/kernel/kprobes.c | 79 ++------------------------------------------ 1 file changed, 4 insertions(+), 75 deletions(-) diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c index 7a7df944d798..0e725ca9c60d 100644 --- a/arch/ia64/kernel/kprobes.c +++ b/arch/ia64/kernel/kprobes.c @@ -396,83 +396,11 @@ static void kretprobe_trampoline(void) { } -/* - * At this point the target function has been tricked into - * returning into our trampoline. Lookup the associated instance - * and then: - * - call the handler function - * - cleanup by marking the instance as unused - * - long jump back to the original return address - */ 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 = - ((struct fnptr *)kretprobe_trampoline)->ip; - - 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; - - orig_ret_address = (unsigned long)ri->ret_addr; - 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; - } - - regs->cr_iip = orig_ret_address; - - 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); - - kretprobe_hash_unlock(current, &flags); - - hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) { - hlist_del(&ri->hlist); - kfree(ri); - } + regs->cr_iip = __kretprobe_trampoline_handler(regs, + (unsigned long)kretprobe_trampoline, + NULL); /* * By returning a non-zero value, we are telling * kprobe_handler() that we don't want the post_handler @@ -485,6 +413,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs) { ri->ret_addr = (kprobe_opcode_t *)regs->b0; + ri->fp = NULL; /* Replace the return addr with trampoline addr */ regs->b0 = ((struct fnptr *)kretprobe_trampoline)->ip;