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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83976C6FD1D for ; Wed, 15 Mar 2023 20:17:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231964AbjCOURY (ORCPT ); Wed, 15 Mar 2023 16:17:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36224 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230404AbjCOURX (ORCPT ); Wed, 15 Mar 2023 16:17:23 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 011A01BAE8 for ; Wed, 15 Mar 2023 13:17:21 -0700 (PDT) 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 8A2C8B81F1B for ; Wed, 15 Mar 2023 20:17:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3F93FC433EF; Wed, 15 Mar 2023 20:17:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1678911439; bh=j+bMDDYx+WmIw2aqhuGGvBzdt/kgJcBFB3NjVdgg4Kc=; h=Date:To:From:Subject:From; b=Glm9xOMMkw8zNRPa8+itQ/xFXCU2e1S0ewBLwGN5W7gwhkCUMu3YozS6l7CpBHz9B 9rbNTcO6sCZacOLuZaRSqEP6gIOa+BSX4+NrazmPpfaavHi/qAUnQGfN7ivsmAc+lZ 0QCLsCHuBoByIsNnIxfH6SEzKl8RcO/RpKY6e26s= Date: Wed, 15 Mar 2023 13:17:18 -0700 To: mm-commits@vger.kernel.org, willy@infradead.org, surenb@google.com, lstoakes@gmail.com, Liam.Howlett@oracle.com, vbabka@suse.cz, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-mmap-vma_merge-use-the-proper-vma-pointer-in-case-3.patch added to mm-unstable branch Message-Id: <20230315201719.3F93FC433EF@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm/mmap/vma_merge: use the proper vma pointer in case 3 has been added to the -mm mm-unstable branch. Its filename is mm-mmap-vma_merge-use-the-proper-vma-pointer-in-case-3.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-mmap-vma_merge-use-the-proper-vma-pointer-in-case-3.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Vlastimil Babka Subject: mm/mmap/vma_merge: use the proper vma pointer in case 3 Date: Thu, 9 Mar 2023 12:12:50 +0100 In case 3 we we use 'next' for everything but vma_pgoff. So use 'next' for that as well, instead of 'mid', for consistency. Then in case 8 we have to use 'mid' explicitly, which should also make the intent more obvious. Adjust the diagram for cases 1-3 in the comment to match the code - we are using 'next' for case 3 so mark the range with XXXX instead of NNNN. For case 2 that's a no-op as the code doesn't touch 'next' or 'mid'. For case 1 it's now wrong but that will be fixed next. No functional change. Link: https://lkml.kernel.org/r/20230309111258.24079-3-vbabka@suse.cz Signed-off-by: Vlastimil Babka Reviewed-by: Lorenzo Stoakes Cc: Liam R. Howlett Cc: Matthew Wilcox (Oracle) Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton --- mm/mmap.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) --- a/mm/mmap.c~mm-mmap-vma_merge-use-the-proper-vma-pointer-in-case-3 +++ a/mm/mmap.c @@ -870,11 +870,11 @@ can_vma_merge_after(struct vm_area_struc * mmap, brk or case 4 below case 5 below * mremap move: * AAAA AAAA - * PPPP NNNN PPPPNNNNXXXX + * PPPP XXXX PPPPNNNNXXXX * might become might become * PPPPPPPPPPPP 1 or PPPPPPPPPPPP 6 or - * PPPPPPPPNNNN 2 or PPPPPPPPXXXX 7 or - * PPPPNNNNNNNN 3 PPPPXXXXXXXX 8 + * PPPPPPPPXXXX 2 or PPPPPPPPXXXX 7 or + * PPPPXXXXXXXX 3 PPPPXXXXXXXX 8 * * It is important for case 8 that the vma NNNN overlapping the * region AAAA is never going to extended over XXXX. Instead XXXX must @@ -991,9 +991,10 @@ struct vm_area_struct *vma_merge(struct vma = next; /* case 3 */ vma_start = addr; vma_end = next->vm_end; - vma_pgoff = mid->vm_pgoff; + vma_pgoff = next->vm_pgoff; err = 0; if (mid != next) { /* case 8 */ + vma_pgoff = mid->vm_pgoff; remove = mid; err = dup_anon_vma(next, mid); } _ Patches currently in -mm which might be from vbabka@suse.cz are mm-page_alloc-reduce-page-alloc-free-sanity-checks.patch mm-mmap-vma_merge-use-only-primary-pointers-for-preparing-merge.patch mm-mmap-vma_merge-use-the-proper-vma-pointer-in-case-3.patch mm-mmap-vma_merge-use-the-proper-vma-pointers-in-cases-1-and-6.patch mm-mmap-vma_merge-use-the-proper-vma-pointer-in-case-4.patch mm-mmap-vma_merge-initialize-mid-and-next-in-natural-order.patch mm-mmap-vma_merge-set-mid-to-null-if-not-applicable.patch mm-mmap-vma_merge-rename-adj_next-to-adj_start.patch mm-mmap-vma_merge-convert-mergeability-checks-to-return-bool.patch mm-mmap-start-distinguishing-if-vma-can-be-removed-in-mergeability-test.patch mm-mremap-simplify-vma-expansion-again.patch