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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 2D840C2D0DA for ; Sun, 29 Dec 2019 17:54:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 080B621744 for ; Sun, 29 Dec 2019 17:54:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577642064; bh=Qi68X8EwhjNhQItLrrrp7bt6hKwH5qQyWhw0sntgeU4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=mIAdu7zqYiIxV31qhvgAclYuOzbviLE2TFT4ukoXv8th79Z/I8VI/hROYKyb8mGGM tKnX8NDjyEXmtr0mSbwJvAS3YywQ6W0jn46dCbslZdzGXUVt4b+df11OKwgPaDqkeH ZzDfS0J74bAAuyoreeeu1oeDw+O1iH9Pd1/Xi3yw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732392AbfL2RyW (ORCPT ); Sun, 29 Dec 2019 12:54:22 -0500 Received: from mail.kernel.org ([198.145.29.99]:42122 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732674AbfL2RyV (ORCPT ); Sun, 29 Dec 2019 12:54:21 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 C645920748; Sun, 29 Dec 2019 17:54:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577642060; bh=Qi68X8EwhjNhQItLrrrp7bt6hKwH5qQyWhw0sntgeU4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qh6BdGJv68B/ttquu+HJ1i+WwcE/OLB7BbKHU0/w9u1XjiiyQ6JNXAOMuQPLrCABd dZcfiibEJBhrodomRkFmr3idypRnRWdZ5Kf0QW+j3T64dEzHWyg469t7R/VW/efXnR btGC43PWHkYOYT8bKAWeCwkrRGJ7ZIeNySl7Md9M= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Thomas Richter , Alexander Shishkin , Peter Zijlstra , Arnaldo Carvalho de Melo , Jiri Olsa , Linus Torvalds , Mark Rutland , Namhyung Kim , Stephane Eranian , Thomas Gleixner , Vince Weaver , Ingo Molnar , Sasha Levin Subject: [PATCH 5.4 323/434] perf/core: Fix the mlock accounting, again Date: Sun, 29 Dec 2019 18:26:16 +0100 Message-Id: <20191229172723.424194731@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191229172702.393141737@linuxfoundation.org> References: <20191229172702.393141737@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Alexander Shishkin [ Upstream commit 36b3db03b4741b8935b68fffc7e69951d8d70a89 ] Commit: 5e6c3c7b1ec2 ("perf/aux: Fix tracking of auxiliary trace buffer allocation") tried to guess the correct combination of arithmetic operations that would undo the AUX buffer's mlock accounting, and failed, leaking the bottom part when an allocation needs to be charged partially to both user->locked_vm and mm->pinned_vm, eventually leaving the user with no locked bonus: $ perf record -e intel_pt//u -m1,128 uname [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.061 MB perf.data ] $ perf record -e intel_pt//u -m1,128 uname Permission error mapping pages. Consider increasing /proc/sys/kernel/perf_event_mlock_kb, or try again with a smaller value of -m/--mmap_pages. (current value: 1,128) Fix this by subtracting both locked and pinned counts when AUX buffer is unmapped. Reported-by: Thomas Richter Tested-by: Thomas Richter Signed-off-by: Alexander Shishkin Acked-by: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Mark Rutland Cc: Namhyung Kim Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- kernel/events/core.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 00a014670ed0..8f66a4833ded 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -5607,10 +5607,8 @@ static void perf_mmap_close(struct vm_area_struct *vma) perf_pmu_output_stop(event); /* now it's safe to free the pages */ - if (!rb->aux_mmap_locked) - atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); - else - atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); + atomic_long_sub(rb->aux_nr_pages - rb->aux_mmap_locked, &mmap_user->locked_vm); + atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); /* this has to be the last one */ rb_free_aux(rb); -- 2.20.1