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=-9.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED,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 DA4DFC28CC2 for ; Thu, 30 May 2019 04:31:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AB1DA25639 for ; Thu, 30 May 2019 04:31:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559190675; bh=N70H1+R5SeViVNqndvuL3AyU8G493F/y+Q0HGRBG2lk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xd/3HHhojNabM3/otq5Rfb9ynT0sqc5NglvxZ8wvFAcvkRI5gITYjyeiKgGjuPczv OrMPtS/VzDFnunLEiaE9TunfMIjkked4qmCk/jaq11ZwWdThP1swLWA0Csr3WIkoBA jBGtXgmHwCvgqW3e/Hggqzqwr8v2fivmJTbkYAcc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729593AbfE3DNs (ORCPT ); Wed, 29 May 2019 23:13:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:51620 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727829AbfE3DLj (ORCPT ); Wed, 29 May 2019 23:11:39 -0400 Received: from localhost (ip67-88-213-2.z213-88-67.customer.algx.net [67.88.213.2]) (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 F08AC244EA; Thu, 30 May 2019 03:11:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559185899; bh=N70H1+R5SeViVNqndvuL3AyU8G493F/y+Q0HGRBG2lk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Bw0jiVKwe8YWGQi6AOF7bcbpWNuwNjmZvAG5UCC+mmtVtqwbGCrg+UOwFb7MwcgVj H2HeSObD3uDGdQPKyacCD/tacLcKSuXrcr1YSvHE706Ls/U3XeBkt7Et6rd61/Tu4r YNRJlaPA9cMuWQabMnEvCG/N//QfJGfYrQdwsPgA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Peter Zijlstra (Intel)" , Borislav Petkov , Josh Poimboeuf , Linus Torvalds , Steven Rostedt , Thomas Gleixner , Ingo Molnar , Sasha Levin Subject: [PATCH 5.1 265/405] x86/uaccess, ftrace: Fix ftrace_likely_update() vs. SMAP Date: Wed, 29 May 2019 20:04:23 -0700 Message-Id: <20190530030554.342021224@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190530030540.291644921@linuxfoundation.org> References: <20190530030540.291644921@linuxfoundation.org> User-Agent: quilt/0.66 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 [ Upstream commit 4a6c91fbdef846ec7250b82f2eeeb87ac5f18cf9 ] For CONFIG_TRACE_BRANCH_PROFILING=y the likely/unlikely things get overloaded and generate callouts to this code, and thus also when AC=1. Make it safe. Signed-off-by: Peter Zijlstra (Intel) Cc: Borislav Petkov Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- kernel/trace/trace_branch.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c index 4ad967453b6fb..3ea65cdff30d5 100644 --- a/kernel/trace/trace_branch.c +++ b/kernel/trace/trace_branch.c @@ -205,6 +205,8 @@ void trace_likely_condition(struct ftrace_likely_data *f, int val, int expect) void ftrace_likely_update(struct ftrace_likely_data *f, int val, int expect, int is_constant) { + unsigned long flags = user_access_save(); + /* A constant is always correct */ if (is_constant) { f->constant++; @@ -223,6 +225,8 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val, f->data.correct++; else f->data.incorrect++; + + user_access_restore(flags); } EXPORT_SYMBOL(ftrace_likely_update); -- 2.20.1