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 9971EE7D0A2 for ; Thu, 21 Sep 2023 18:25:32 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 281806B024D; Thu, 21 Sep 2023 14:25:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 232316B024E; Thu, 21 Sep 2023 14:25:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0F9B36B024F; Thu, 21 Sep 2023 14:25:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id F3D846B024D for ; Thu, 21 Sep 2023 14:25:31 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id CB4C640BEE for ; Thu, 21 Sep 2023 18:25:31 +0000 (UTC) X-FDA: 81261432462.27.8DF1EF9 Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by imf19.hostedemail.com (Postfix) with ESMTP id 26CA11A0022 for ; Thu, 21 Sep 2023 18:25:27 +0000 (UTC) Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=Eo3kx3Q6; dmarc=none; spf=pass (imf19.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1695320728; 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=/HSvvHOk/ZrIHPVIIpIgGipQMiDnjcUMeHBVcOsg2Mk=; b=xe8e08HXHLN5hdtYu/Y5lEbUCFg/mo9NO9ocCcYGIMEelalSBxIZAwPLmrI7tNr+5K/Xg2 kJAmvp0Chai4vU9AVlHGkreXkc4C9M3ZAZ1yWmN4gy8I13Xi2THdL3KI10cfapaGrVNNzK zbUCcHXzF+4tv+5zhtozR1JKIkq4PE4= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=Eo3kx3Q6; dmarc=none; spf=pass (imf19.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1695320728; a=rsa-sha256; cv=none; b=A8TQd+uR5QrNZNJTBzyuF3pHX221TU4+3X4K44xtbn+vkyNLd0rxJ4OuPQVtspPuSPM96V JwDK9pf1mn3B3JUGUz8mQ0+6n3fXYa0XEPkHpPah/jRQkeHAFO/itwx2WVl2zNw5/jrXDm ndg61MADfyH2Advbu9jT3rrG21fMme0= Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 2E908CE22C2; Thu, 21 Sep 2023 18:25:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2099DC433C8; Thu, 21 Sep 2023 18:25:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1695320722; bh=atHxn0oP50X39viOIJkKSajTFqVn3mXPy8q7EkWVcDU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Eo3kx3Q6ZdtBz4kiW13CIgphmBIWEst+/HoN5gH898ESRwiPd7KkOwllJAYDXEAuZ xHYfWg+Nu8dFuFpNPfeIKtlBq2KwvIM2jr23U+54k0CrPspE1DLUHLMTgDax/fQGHP i/b+II2ktSKCdDTjn/jSs76wY7dHogEP+pCvryhQ= Date: Thu, 21 Sep 2023 11:25:21 -0700 From: Andrew Morton To: "Liam R. Howlett" Cc: maple-tree@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, pedro.falcato@gmail.com, stable Subject: Re: [PATCH 0/2] maple_tree: Fix mas_prev() state regression. Message-Id: <20230921112521.fc07c658804f4e188179da77@linux-foundation.org> In-Reply-To: <20230921181236.509072-1-Liam.Howlett@oracle.com> References: <20230921181236.509072-1-Liam.Howlett@oracle.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 26CA11A0022 X-Stat-Signature: go1gjci4e6ykaty3rhxktfu7zc7h15dm X-HE-Tag: 1695320727-80711 X-HE-Meta: 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 r13n+AFA 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 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 Thu, 21 Sep 2023 14:12:34 -0400 "Liam R. Howlett" wrote: > Pedro Falcato contacted me on IRC with an mprotect regression which was > bisected back to the iterator changes for maple tree. Root cause > analysis showed the mas_prev() running off the end of the VMA space > (previous from 0) followed by mas_find(), would skip the first value. > > This patch set introduces maple state underflow/overflow so the sequence > of calls on the maple state will return what the user expects. It isn't clear what are the user-visible effects of this flaw? Please send this along and I'll paste it in. Patch 1 should be titled "Add mas_is_active ...". And patch 1 should have had cc:stable in the changelog. It's stable@vger.kernel.org, although stable@kernel.org works just fine.