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=-14.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 49804C433E2 for ; Mon, 14 Sep 2020 17:19:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 01E44217BA for ; Mon, 14 Sep 2020 17:19:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="IPuND0N6"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="/64/E3XX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726064AbgINRTm (ORCPT ); Mon, 14 Sep 2020 13:19:42 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:34832 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725994AbgINRQ0 (ORCPT ); Mon, 14 Sep 2020 13:16:26 -0400 Date: Mon, 14 Sep 2020 17:16:17 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1600103778; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=QLG9yEbhfzjKMQOnGAENID9F89xkk0rQSS9rVo4eL3o=; b=IPuND0N6ZhiTMYXIs7pCa33wmmGuVU3kIW3dL7UqSbwcrXikmUKF+Gd/II9sB0NDq/r1ar ePrmqymV/xVUmV9Jmu7Xeqjsjfjo9bWinWwCXzAMcw9BLHco7DWFVvLlCPAPj9WPAhV//k Hz3KUIPe0Wd8//It5u1+fefxhoGaBQqhuz3V7bh6tAe9Wfy/pfZzjXI/fIVy5rT35Lr2sf aZgLRiojMwpPZ2gofKkZyFceeItRrj/gMfyn4LI2yidbKbDkADMSb6OF/4M2slT61OJZHA SgwpiAy9NU3g4vokJEJ0RpkOw+dMQtMsKBAO49dF6szMlVZAfdMMBM9MHFaEGA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1600103778; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=QLG9yEbhfzjKMQOnGAENID9F89xkk0rQSS9rVo4eL3o=; b=/64/E3XXoQ5q2EyfZeQvlL8cyQHwngjA0gTTlmGJjVNM7rxEk89qyfW+oBQwtSRyxjpMyr uxvhDGHIdBwQ8fBw== From: "tip-bot2 for Masami Hiramatsu" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: perf/kprobes] powerpc: kprobes: Use generic kretprobe trampoline handler Cc: Masami Hiramatsu , Ingo Molnar , x86 , LKML In-Reply-To: <159870610825.1229682.2090635992093223399.stgit@devnote2> References: <159870610825.1229682.2090635992093223399.stgit@devnote2> MIME-Version: 1.0 Message-ID: <160010377739.15536.14273758940900599982.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the perf/kprobes branch of tip: Commit-ID: b6c5a58dd89e683e66b52a57a6f022fda79a0aab Gitweb: https://git.kernel.org/tip/b6c5a58dd89e683e66b52a57a6f022fda79a0aab Author: Masami Hiramatsu AuthorDate: Sat, 29 Aug 2020 22:01:48 +09:00 Committer: Ingo Molnar CommitterDate: Tue, 08 Sep 2020 11:52:34 +02:00 powerpc: kprobes: Use generic kretprobe trampoline handler Use the generic kretprobe trampoline handler. Don't use framepointer verification. Signed-off-by: Masami Hiramatsu Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/159870610825.1229682.2090635992093223399.stgit@devnote2 --- arch/powerpc/kernel/kprobes.c | 53 +--------------------------------- 1 file changed, 3 insertions(+), 50 deletions(-) diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c index 6ab9b4d..01ab216 100644 --- a/arch/powerpc/kernel/kprobes.c +++ b/arch/powerpc/kernel/kprobes.c @@ -218,6 +218,7 @@ bool arch_kprobe_on_func_entry(unsigned long offset) void arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs) { ri->ret_addr = (kprobe_opcode_t *)regs->link; + ri->fp = NULL; /* Replace the return addr with trampoline addr */ regs->link = (unsigned long)kretprobe_trampoline; @@ -396,50 +397,9 @@ asm(".global kretprobe_trampoline\n" */ static int 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); + unsigned long orig_ret_address; + orig_ret_address = __kretprobe_trampoline_handler(regs, &kretprobe_trampoline, NULL); /* * We get here through one of two paths: * 1. by taking a trap -> kprobe_handler() -> here @@ -458,13 +418,6 @@ static int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) regs->nip = orig_ret_address - 4; regs->link = 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 0; } NOKPROBE_SYMBOL(trampoline_probe_handler);