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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 20BE5C19F2B for ; Thu, 4 Aug 2022 09:02:31 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 536E78E0002; Thu, 4 Aug 2022 05:02:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4E87A8E0001; Thu, 4 Aug 2022 05:02:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3AF2E8E0002; Thu, 4 Aug 2022 05:02:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 2C5778E0001 for ; Thu, 4 Aug 2022 05:02:31 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id EF246161774 for ; Thu, 4 Aug 2022 09:02:30 +0000 (UTC) X-FDA: 79761319260.09.8145F96 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by imf28.hostedemail.com (Postfix) with ESMTP id 80BD7C0111 for ; Thu, 4 Aug 2022 09:02:30 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id B9672B824BC; Thu, 4 Aug 2022 09:02:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E6F41C433C1; Thu, 4 Aug 2022 09:02:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1659603747; bh=FAPfqA1BxBDBpuGmMp4lrKxBMRFkiCvMfk1ZhdaiILU=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=FWyGBxsrtOB1KMNgNyEQbv3S8yu+winatVk5BpuKktdEOAdZZyG4yBO8hOV44MAFm dkVdd9K/+tjAQeGziwZ3kJOZdW/ayltIfNPNc6ushjpaDUtz6jHGwbfoGtWbTAQ5zC 5rwzdvm1Dqr0Vlbj18K2fHedmqWAwOfJajvqxmZuHzqDpci8GFqVNFiY3IGx+JzztU CdlpMiWhzvrip4bDiEhzLpGihy59smtyrXLe24Sune6EnWx/XNjwjiVwHfl5zfcGKf +b5hhB9DHoAsChP4WlKuilVqQ0HOpZS5ztTtNbgHVvsvWKVYHKhgbPNEy/CNOboynf KTupq2v4yVTwg== Message-ID: Date: Thu, 4 Aug 2022 11:02:23 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.0.3 Subject: Re: [PATCH] mm/smaps: Don't access young/dirty bit if pte unpresent To: Peter Xu , linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: Yang Shi , Andrew Morton , Nadav Amit , David Hildenbrand , Konstantin Khlebnikov References: <20220803220329.46299-1-peterx@redhat.com> Content-Language: en-US From: "Vlastimil Babka (SUSE)" In-Reply-To: <20220803220329.46299-1-peterx@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1659603750; a=rsa-sha256; cv=none; b=2LByZY2HU5a6d3PwIic3IMz5NPfzr20gGvmLvRuznjfAOmnK02/S0YtXaZFKSuwpXz+CuN QRKSczXyED8B+j+GedKSqBSfqerKYkmvL1tCB/CVOuzTi2iR26wsETtATYfsbrzqTO0DWU ytUw7Z0j4qa8n3MxIcx2ob+lKH7UtLM= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=FWyGBxsr; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf28.hostedemail.com: domain of vbabka@kernel.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=vbabka@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1659603750; h=from:from:sender: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:dkim-signature; bh=vZsrw/m51nWZYZewwerLfK+ZBoRiEkemkicLZgycD+M=; b=mpp6i0L+zX/Nb2Bp3017z5yBYN6jecthrOld6wTvGXwKwuxpfdhpnjOQfFbeKE8DN8rBt3 tKNsYb4jrBCfNryZ+ghXJ20axMdpP4Zh0JelVeI+S2GrsGP9vczFPLSYat/qkhqSJeUv6V Trc6P8s289wj/TZr4IOSv+ubzrcfCz0= Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=FWyGBxsr; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf28.hostedemail.com: domain of vbabka@kernel.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=vbabka@kernel.org X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 80BD7C0111 X-Rspam-User: X-Stat-Signature: t1fnyc5xcuwcybnghjyrhjmamwuwn8pk X-HE-Tag: 1659603750-873983 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 8/4/22 00:03, Peter Xu wrote: > These bits should only be valid when the ptes are present. Introducing two > booleans for it and set it to false when !pte_present(). > > Cc: Konstantin Khlebnikov > Fixes: b1d4d9e0cbd0 ("proc/smaps: carefully handle migration entries", 2012-05-31) > Signed-off-by: Peter Xu Acked-by: Vlastimil Babka > --- > fs/proc/task_mmu.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c > index 9913f3be9fd2..482f91577f8c 100644 > --- a/fs/proc/task_mmu.c > +++ b/fs/proc/task_mmu.c > @@ -527,10 +527,12 @@ static void smaps_pte_entry(pte_t *pte, unsigned long addr, > struct vm_area_struct *vma = walk->vma; > bool locked = !!(vma->vm_flags & VM_LOCKED); > struct page *page = NULL; > - bool migration = false; > + bool migration = false, young = false, dirty = false; > > if (pte_present(*pte)) { > page = vm_normal_page(vma, addr, *pte); > + young = pte_young(*pte); > + dirty = pte_dirty(*pte); > } else if (is_swap_pte(*pte)) { > swp_entry_t swpent = pte_to_swp_entry(*pte); > > @@ -560,8 +562,7 @@ static void smaps_pte_entry(pte_t *pte, unsigned long addr, > if (!page) > return; > > - smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte), > - locked, migration); > + smaps_account(mss, page, false, young, dirty, locked, migration); > } > > #ifdef CONFIG_TRANSPARENT_HUGEPAGE