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 7FDF1C25B76 for ; Thu, 6 Jun 2024 00:51:22 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id DCE186B009E; Wed, 5 Jun 2024 20:51:21 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D7C496B009F; Wed, 5 Jun 2024 20:51:21 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C1D7A6B00A0; Wed, 5 Jun 2024 20:51:21 -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 9F7F66B009E for ; Wed, 5 Jun 2024 20:51:21 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 5627FA190B for ; Thu, 6 Jun 2024 00:51:21 +0000 (UTC) X-FDA: 82198635162.27.66CAF36 Received: from mail-yb1-f176.google.com (mail-yb1-f176.google.com [209.85.219.176]) by imf29.hostedemail.com (Postfix) with ESMTP id 9A4C6120009 for ; Thu, 6 Jun 2024 00:51:19 +0000 (UTC) Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=QCg2+j5q; spf=pass (imf29.hostedemail.com: domain of surenb@google.com designates 209.85.219.176 as permitted sender) smtp.mailfrom=surenb@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1717635079; 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=f+cCaO4GQQZF5arDTs75VRTDY7XKwvZ01IHsyj7Khdo=; b=ndrkEzIMrndxS4vUzppVRIssv4Dspb2NAEbDORMJvPMvMHJfhdAEXwrYTebWaWCgdxcoGd DPuulRe31tOARwp4k0KW2dJ3HkjZUKp+3sJEVvz3CJdMD035s15KZ+ohDvohdZk9Sbg1f4 pW51b9aiHqu7dDSsA07R3IyccUvWZYU= ARC-Authentication-Results: i=1; imf29.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=QCg2+j5q; spf=pass (imf29.hostedemail.com: domain of surenb@google.com designates 209.85.219.176 as permitted sender) smtp.mailfrom=surenb@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1717635079; a=rsa-sha256; cv=none; b=CdmT9XTDBzLD+o4E/t5h8C98teQsV4LmEXjUKOYKxiKZ/jMPBZUhGcUtmwxlCUzanA7zkY IFaj6aksvaQrJZT1PeVzI4OWTcqWiK82t4dry4nqEBoG+j/KkEFTms8sDk7EF8CTgwJTlf uv2u4q5cIayX43cttdsEkGtX8XK+qB4= Received: by mail-yb1-f176.google.com with SMTP id 3f1490d57ef6-dfa682a4025so501115276.2 for ; Wed, 05 Jun 2024 17:51:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1717635078; x=1718239878; darn=kvack.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=f+cCaO4GQQZF5arDTs75VRTDY7XKwvZ01IHsyj7Khdo=; b=QCg2+j5qSikEainupeNOP+QDON3v7dHIxAffZZSC0JuVnyvVQVXfTuSVLFgCNHdMSJ 9ajpKn08mR0EXr1zvysdryMHER6NaiFFUOdQyVVdVbSG14OnuKxPEMx80vcUF893/oj8 QrorEkYggiCbQNb86Aao8xTEMke5VIWoCnRnQk2qsSNnVw7yZl3V800cc9QqckoBTvye gF8SuElj6Xi0Su4aAlzgsNNJv2JBBOAmPpk1Aha4F9LEpmdF9oDV9apskAJiAPdGFgR9 OAj9BMG0ejnlT8sK33KJsBGPX39gDN4g0aUUjQz77lemeLSchS0NqqeGW5BNr74a7qnK oWdQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1717635078; x=1718239878; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=f+cCaO4GQQZF5arDTs75VRTDY7XKwvZ01IHsyj7Khdo=; b=NHmq0hd+a+03GseneU2Xf5Oclm/xvpbv7pFKAUGrQhycGIhezpcD0+LbV2QfqcWHsc uysaAvpZhTz96C1RJ47Zh6ySzV0U4L0jsDFZadZYn+GMmNQyV7mIjJueH8TC0Z16Wp5G A9TtV7xGPMj/WRN/9dlXU4oH1DYYB7ezn6aCtsvxpT+fmDTAA5p/0jT83c8lCiLJm1HB SiMqYAXvZ9+I45qa/sOcHghAHj18BF/7eLvcjPyF3XlA9Amc1bkjydJhaK+H3arwsBAA jHAl6QuNiYhNs6e2fM2GM9Uff3IXShAi7dcAnOqVJpb8dm7lZVBgtqolee8hGxM5GE/I N2qQ== X-Forwarded-Encrypted: i=1; AJvYcCWZ1uloslPlWd3ogkl8t49ElXehR9fTcNla/bmWzcNNgHdElVQjW7QFvsY8+NrScu6/ctRT2bs240xk+95M6v5/rY4= X-Gm-Message-State: AOJu0Ywjl9eRw6ZoRJ+VuV21PDQgkWcJHTma5wCPUK57tE+zEintzLUG ZmlSdl63dRLMStlaYKwSuLnRbLEJeFZAPungGJhww5MTvBqDluW+JGB106oPu7K+toMS1ENyOE4 81af4LOBqw9hFjNEnEEuiN8SZWTObBowu7XjV X-Google-Smtp-Source: AGHT+IEsn/LiMweS6R6p+zt8kRJUiTPyCnADdmFz9d/yv/LTm6IC2uClrAE9Un5+DNW2ZVH+y0uZPZJi/Z0fKwigOaM= X-Received: by 2002:a05:6902:4c4:b0:dfa:e131:2a8e with SMTP id 3f1490d57ef6-dfae1313607mr704141276.47.1717635078316; Wed, 05 Jun 2024 17:51:18 -0700 (PDT) MIME-Version: 1.0 References: <20240531163217.1584450-1-Liam.Howlett@oracle.com> <20240531163217.1584450-2-Liam.Howlett@oracle.com> In-Reply-To: <20240531163217.1584450-2-Liam.Howlett@oracle.com> From: Suren Baghdasaryan Date: Wed, 5 Jun 2024 17:51:05 -0700 Message-ID: Subject: Re: [RFC PATCH 1/5] mm/mmap: Correctly position vma_iterator in __split_vma() To: "Liam R. Howlett" Cc: Andrii Nakryiko , Vlastimil Babka , sidhartha.kumar@oracle.com, Matthew Wilcox , Lorenzo Stoakes , linux-fsdevel@vger.kernel.org, bpf@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: h8digx1imu1p1px86f1hd558tspukr4b X-Rspamd-Queue-Id: 9A4C6120009 X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1717635079-54653 X-HE-Meta: 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 Rn6DfDwy aH1gj8ssdy1H0tX9pjDSBrTM3I9YQxXQtWs8RlKd82RDcdMhmO9OYtB4C8nqCUemqi0h/p0tyLA9bYVkQIz5+zKGJerwdgPdnDmKhhPkEeLfayIzz7K66/BUF5n5ES+45MMcG8M/zPcNGQvUs7rWbenQlCRNHgezz92qd1szRLH4/mRjOJd5Wvu3kWl797OfSh2HWAAofzVJ++wisPWWils5XiCDGYFPrATgdJFu9nRDM87gYsqaKwK6PMnOcL4pPzuFyIw6/etCLDTNc7H8FHA1EI1czEyNzGno53uHyOAS4LDDP/A0W1eU2EzZsVrys0jbZQrg2ZBlqrMc/RNxLpJ0nGgPrGV7dafrCe6T50Q7yeTvQRQHCZ0pvUJs17JurtvwG+vM8kMJm8Ag= X-Bogosity: Ham, tests=bogofilter, spamicity=0.004781, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, May 31, 2024 at 9:33=E2=80=AFAM Liam R. Howlett wrote: > > The vma iterator may be left pointing to the newly created vma. This > happens when inserting the new vma at the end of the old vma > (!new_below). > > The incorrect position in the vma iterator is not exposed currently > since the vma iterator is repositioned in the munmap path and is not > reused in any of the other paths. > > This has limited impact in the current code, but is required for future > changes. > > Fixes: b2b3b886738f ("mm: don't use __vma_adjust() in __split_vma()") > Signed-off-by: Liam R. Howlett > --- > mm/mmap.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/mm/mmap.c b/mm/mmap.c > index 83b4682ec85c..31d464e6a656 100644 > --- a/mm/mmap.c > +++ b/mm/mmap.c > @@ -2442,6 +2442,9 @@ static int __split_vma(struct vma_iterator *vmi, st= ruct vm_area_struct *vma, > /* Success. */ > if (new_below) > vma_next(vmi); > + else > + vma_prev(vmi); > + IIUC the goal is to always point vmi to the old (original) vma? If so, then change LGTM. Reviewed-by: Suren Baghdasaryan > return 0; > > out_free_mpol: > -- > 2.43.0 >