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=-24.8 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 84EABC433DB for ; Fri, 19 Mar 2021 01:28:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D19E64E0C for ; Fri, 19 Mar 2021 01:28:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232123AbhCSB21 (ORCPT ); Thu, 18 Mar 2021 21:28:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56666 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230507AbhCSB2F (ORCPT ); Thu, 18 Mar 2021 21:28:05 -0400 Received: from mail-qt1-x832.google.com (mail-qt1-x832.google.com [IPv6:2607:f8b0:4864:20::832]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3A2ABC06174A for ; Thu, 18 Mar 2021 18:28:05 -0700 (PDT) Received: by mail-qt1-x832.google.com with SMTP id c6so5662577qtc.1 for ; Thu, 18 Mar 2021 18:28:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:in-reply-to:message-id:references :user-agent:mime-version; bh=QYfvSSwIRM7Kw1Y7cxuBdnKVSS5fwftsdnBQc9yOiTg=; b=oxhP9vsbtr97ag/pvOX+KBsfTvkBPfrAijHzttvNvrb4EUc/wKOdyQ6tdW447WlfO/ tgb/SN89hmcgZSO/fYwaqdZXqimz0o4X1UEdms09HL5MZCDG+j5FOi58NpkqPqI/1PS/ AusQqX3tsA+R+wNL/Vl4AyG4qykHMbmUcSvdXfBKAhshcJDdZLu/no1pfWAV7Lcme+Ml eQ6OiWVpVjT07GZOzJIZhVR5FwsOE167cnlxNqRt/PYbkYja+hvuBaL5dNShN6Yo7FNK of4+zZY0Ks8GuAro9CRo4M1xxa4ogDcO/+1jgZHsz1cy5uN5gr6zwBet+rKfbmYWuy0c wG8A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:in-reply-to:message-id :references:user-agent:mime-version; bh=QYfvSSwIRM7Kw1Y7cxuBdnKVSS5fwftsdnBQc9yOiTg=; b=i6kesSwdHU+1ckcs7RzuFiOmeQHsoibSvrzX+StJUxXaQ8PXf2ENFSXmh2Q4eHzLdp TEDjSWotp4y4TNbvkA2kG/OiUZHfOQKV2A+wa89yPwdessPDcwTOS6BhGyQdS0ozAjw3 fJDBFVhL46o7qtCp1akuPJ++2bxqzh1BFlGmU6QUfuuqWpCIVic+2Zm/Ry6l+lWmkxwh tqVdyqFUwkEfrbYDnCkp6xZkip8bRq1YDqvDbIWfp1ewNnZytxRblnM0eZkd0BWdCUGB TBKgNZZvsQ6UMiZrknCtGdnN7458XUXM/3ko2TmJDIdwH3KF6XZ7h2SpbRzOsA+yJYHh 5r0A== X-Gm-Message-State: AOAM533J1LgQY+B9R5zTKZDzx6KIefRVUZ6wfQ9bCG52WgzkcNMczN74 Q2D3DlYSFoWZmjY3CN4HQ7imJw== X-Google-Smtp-Source: ABdhPJz34yYhDmqv+OZzhMLLAT97VnDI6x7JoyZ1JyI7k/lUVDXhEOS8YIwpFXzMsHUxnZcjrgkN+A== X-Received: by 2002:aed:306c:: with SMTP id 99mr6321771qte.352.1616117284212; Thu, 18 Mar 2021 18:28:04 -0700 (PDT) Received: from eggly.attlocal.net (172-10-233-147.lightspeed.sntcca.sbcglobal.net. [172.10.233.147]) by smtp.gmail.com with ESMTPSA id a20sm3206084qkg.61.2021.03.18.18.28.02 (version=TLS1 cipher=ECDHE-ECDSA-AES128-SHA bits=128/128); Thu, 18 Mar 2021 18:28:03 -0700 (PDT) Date: Thu, 18 Mar 2021 18:28:01 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@eggly.anvils To: Brian Geffon cc: Andrew Morton , Axel Rasmussen , Lokesh Gidra , Mike Rapoport , Peter Xu , Hugh Dickins , "Michael S . Tsirkin" , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andy Lutomirski , Vlastimil Babka , Andrea Arcangeli , Sonny Rao , Minchan Kim , "Kirill A . Shutemov" , Dmitry Safonov Subject: Re: [PATCH v3 2/2] Revert "mremap: don't allow MREMAP_DONTUNMAP on special_mappings and aio" In-Reply-To: <20210317214147.682687-2-bgeffon@google.com> Message-ID: References: <20210303175235.3308220-1-bgeffon@google.com> <20210317214147.682687-1-bgeffon@google.com> <20210317214147.682687-2-bgeffon@google.com> User-Agent: Alpine 2.11 (LSU 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 17 Mar 2021, Brian Geffon wrote: > This reverts commit cd544fd1dc9293c6702fab6effa63dac1cc67e99. > > As discussed in [1] this commit was a no-op because the mapping type was > checked in vma_to_resize before move_vma is ever called. This meant that > vm_ops->mremap() would never be called on such mappings. Furthermore, > we've since expanded support of MREMAP_DONTUNMAP to non-anonymous > mappings, and these special mappings are still protected by the existing > check of !VM_DONTEXPAND and !VM_PFNMAP which will result in a -EFAULT. One small fixup needed: -EFAULT was what the incorrect v2 gave, but v3 issues -EINVAL like before, and I'm content with that difference. > > 1. https://lkml.org/lkml/2020/12/28/2340 > > Signed-off-by: Brian Geffon Acked-by: Hugh Dickins Thanks Brian, I'm happy with this result. > --- > arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 2 +- > fs/aio.c | 5 +---- > include/linux/mm.h | 2 +- > mm/mmap.c | 6 +----- > mm/mremap.c | 2 +- > 5 files changed, 5 insertions(+), 12 deletions(-) > > diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c > index e916646adc69..0daf2f1cf7a8 100644 > --- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c > +++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c > @@ -1458,7 +1458,7 @@ static int pseudo_lock_dev_release(struct inode *inode, struct file *filp) > return 0; > } > > -static int pseudo_lock_dev_mremap(struct vm_area_struct *area, unsigned long flags) > +static int pseudo_lock_dev_mremap(struct vm_area_struct *area) > { > /* Not supported */ > return -EINVAL; > diff --git a/fs/aio.c b/fs/aio.c > index 1f32da13d39e..76ce0cc3ee4e 100644 > --- a/fs/aio.c > +++ b/fs/aio.c > @@ -323,16 +323,13 @@ static void aio_free_ring(struct kioctx *ctx) > } > } > > -static int aio_ring_mremap(struct vm_area_struct *vma, unsigned long flags) > +static int aio_ring_mremap(struct vm_area_struct *vma) > { > struct file *file = vma->vm_file; > struct mm_struct *mm = vma->vm_mm; > struct kioctx_table *table; > int i, res = -EINVAL; > > - if (flags & MREMAP_DONTUNMAP) > - return -EINVAL; > - > spin_lock(&mm->ioctx_lock); > rcu_read_lock(); > table = rcu_dereference(mm->ioctx_table); > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 77e64e3eac80..8c3729eb3e38 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -570,7 +570,7 @@ struct vm_operations_struct { > void (*close)(struct vm_area_struct * area); > /* Called any time before splitting to check if it's allowed */ > int (*may_split)(struct vm_area_struct *area, unsigned long addr); > - int (*mremap)(struct vm_area_struct *area, unsigned long flags); > + int (*mremap)(struct vm_area_struct *area); > /* > * Called by mprotect() to make driver-specific permission > * checks before mprotect() is finalised. The VMA must not > diff --git a/mm/mmap.c b/mm/mmap.c > index 3f287599a7a3..9d7651e4e1fe 100644 > --- a/mm/mmap.c > +++ b/mm/mmap.c > @@ -3403,14 +3403,10 @@ static const char *special_mapping_name(struct vm_area_struct *vma) > return ((struct vm_special_mapping *)vma->vm_private_data)->name; > } > > -static int special_mapping_mremap(struct vm_area_struct *new_vma, > - unsigned long flags) > +static int special_mapping_mremap(struct vm_area_struct *new_vma) > { > struct vm_special_mapping *sm = new_vma->vm_private_data; > > - if (flags & MREMAP_DONTUNMAP) > - return -EINVAL; > - > if (WARN_ON_ONCE(current->mm != new_vma->vm_mm)) > return -EFAULT; > > diff --git a/mm/mremap.c b/mm/mremap.c > index db5b8b28c2dd..d22629ff8f3c 100644 > --- a/mm/mremap.c > +++ b/mm/mremap.c > @@ -545,7 +545,7 @@ static unsigned long move_vma(struct vm_area_struct *vma, > if (moved_len < old_len) { > err = -ENOMEM; > } else if (vma->vm_ops && vma->vm_ops->mremap) { > - err = vma->vm_ops->mremap(new_vma, flags); > + err = vma->vm_ops->mremap(new_vma); > } > > if (unlikely(err)) { > -- > 2.31.0.rc2.261.g7f71774620-goog 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=-24.8 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1,USER_IN_DEF_DKIM_WL 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 D4738C433E0 for ; Fri, 19 Mar 2021 01:28:10 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4EBA064E04 for ; Fri, 19 Mar 2021 01:28:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4EBA064E04 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D62D86B006C; Thu, 18 Mar 2021 21:28:09 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D13B96B0071; Thu, 18 Mar 2021 21:28:09 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BDD836B0072; Thu, 18 Mar 2021 21:28:09 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0060.hostedemail.com [216.40.44.60]) by kanga.kvack.org (Postfix) with ESMTP id A0A036B006C for ; Thu, 18 Mar 2021 21:28:09 -0400 (EDT) Received: from smtpin36.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 5EB2287EB for ; Fri, 19 Mar 2021 01:28:09 +0000 (UTC) X-FDA: 77934887898.36.A9E7A37 Received: from mail-qt1-f178.google.com (mail-qt1-f178.google.com [209.85.160.178]) by imf08.hostedemail.com (Postfix) with ESMTP id 5EFAC8019140 for ; Fri, 19 Mar 2021 01:28:02 +0000 (UTC) Received: by mail-qt1-f178.google.com with SMTP id m7so5623747qtq.11 for ; Thu, 18 Mar 2021 18:28:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:in-reply-to:message-id:references :user-agent:mime-version; bh=QYfvSSwIRM7Kw1Y7cxuBdnKVSS5fwftsdnBQc9yOiTg=; b=oxhP9vsbtr97ag/pvOX+KBsfTvkBPfrAijHzttvNvrb4EUc/wKOdyQ6tdW447WlfO/ tgb/SN89hmcgZSO/fYwaqdZXqimz0o4X1UEdms09HL5MZCDG+j5FOi58NpkqPqI/1PS/ AusQqX3tsA+R+wNL/Vl4AyG4qykHMbmUcSvdXfBKAhshcJDdZLu/no1pfWAV7Lcme+Ml eQ6OiWVpVjT07GZOzJIZhVR5FwsOE167cnlxNqRt/PYbkYja+hvuBaL5dNShN6Yo7FNK of4+zZY0Ks8GuAro9CRo4M1xxa4ogDcO/+1jgZHsz1cy5uN5gr6zwBet+rKfbmYWuy0c wG8A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:in-reply-to:message-id :references:user-agent:mime-version; bh=QYfvSSwIRM7Kw1Y7cxuBdnKVSS5fwftsdnBQc9yOiTg=; b=dzC5mgKI4mc9rwaXsUjrDmZAAGTmuo/GCrasJrxJ5eHQ4+Fdr2aCb1A++LNRCvfm8d goPna+1C8ze+P6uyIF99kTu7+026BZUCWBEq0lulMIjWjd+dtSDfhrjroBWGoL/+M/q0 TvRPw/1c/5MKjGYzL4RwzBW10actUoyxZx38bNjMAEri74OZo18dfnq7rRyg8RdT2wOa dHWdiU01vCPumBIAdObRVGV3oqWHLivOJx8XOVmz7Ys+9+O3gDB1c0vN6iJeoPPDVEkt Ti/1mvzHCykIGlnzsdF5Rm349X9b1nkDfyzfTxer4yzWe7FaMIztsZsCSyPin+PBsFoh +qeQ== X-Gm-Message-State: AOAM532+VIV4TDK0ob74RV/Y1WDNauGBu9nqIFWkocBC9LauwdB1Nyun w05iaLBDbcn5rPY8iFQsDRetdw== X-Google-Smtp-Source: ABdhPJz34yYhDmqv+OZzhMLLAT97VnDI6x7JoyZ1JyI7k/lUVDXhEOS8YIwpFXzMsHUxnZcjrgkN+A== X-Received: by 2002:aed:306c:: with SMTP id 99mr6321771qte.352.1616117284212; Thu, 18 Mar 2021 18:28:04 -0700 (PDT) Received: from eggly.attlocal.net (172-10-233-147.lightspeed.sntcca.sbcglobal.net. [172.10.233.147]) by smtp.gmail.com with ESMTPSA id a20sm3206084qkg.61.2021.03.18.18.28.02 (version=TLS1 cipher=ECDHE-ECDSA-AES128-SHA bits=128/128); Thu, 18 Mar 2021 18:28:03 -0700 (PDT) Date: Thu, 18 Mar 2021 18:28:01 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@eggly.anvils To: Brian Geffon cc: Andrew Morton , Axel Rasmussen , Lokesh Gidra , Mike Rapoport , Peter Xu , Hugh Dickins , "Michael S . Tsirkin" , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andy Lutomirski , Vlastimil Babka , Andrea Arcangeli , Sonny Rao , Minchan Kim , "Kirill A . Shutemov" , Dmitry Safonov Subject: Re: [PATCH v3 2/2] Revert "mremap: don't allow MREMAP_DONTUNMAP on special_mappings and aio" In-Reply-To: <20210317214147.682687-2-bgeffon@google.com> Message-ID: References: <20210303175235.3308220-1-bgeffon@google.com> <20210317214147.682687-1-bgeffon@google.com> <20210317214147.682687-2-bgeffon@google.com> User-Agent: Alpine 2.11 (LSU 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Stat-Signature: fppgh6wwk6ae8w5pxj9rq3hd5pf69dt4 X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 5EFAC8019140 Received-SPF: none (google.com>: No applicable sender policy available) receiver=imf08; identity=mailfrom; envelope-from=""; helo=mail-qt1-f178.google.com; client-ip=209.85.160.178 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616117282-741292 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 Wed, 17 Mar 2021, Brian Geffon wrote: > This reverts commit cd544fd1dc9293c6702fab6effa63dac1cc67e99. > > As discussed in [1] this commit was a no-op because the mapping type was > checked in vma_to_resize before move_vma is ever called. This meant that > vm_ops->mremap() would never be called on such mappings. Furthermore, > we've since expanded support of MREMAP_DONTUNMAP to non-anonymous > mappings, and these special mappings are still protected by the existing > check of !VM_DONTEXPAND and !VM_PFNMAP which will result in a -EFAULT. One small fixup needed: -EFAULT was what the incorrect v2 gave, but v3 issues -EINVAL like before, and I'm content with that difference. > > 1. https://lkml.org/lkml/2020/12/28/2340 > > Signed-off-by: Brian Geffon Acked-by: Hugh Dickins Thanks Brian, I'm happy with this result. > --- > arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 2 +- > fs/aio.c | 5 +---- > include/linux/mm.h | 2 +- > mm/mmap.c | 6 +----- > mm/mremap.c | 2 +- > 5 files changed, 5 insertions(+), 12 deletions(-) > > diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c > index e916646adc69..0daf2f1cf7a8 100644 > --- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c > +++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c > @@ -1458,7 +1458,7 @@ static int pseudo_lock_dev_release(struct inode *inode, struct file *filp) > return 0; > } > > -static int pseudo_lock_dev_mremap(struct vm_area_struct *area, unsigned long flags) > +static int pseudo_lock_dev_mremap(struct vm_area_struct *area) > { > /* Not supported */ > return -EINVAL; > diff --git a/fs/aio.c b/fs/aio.c > index 1f32da13d39e..76ce0cc3ee4e 100644 > --- a/fs/aio.c > +++ b/fs/aio.c > @@ -323,16 +323,13 @@ static void aio_free_ring(struct kioctx *ctx) > } > } > > -static int aio_ring_mremap(struct vm_area_struct *vma, unsigned long flags) > +static int aio_ring_mremap(struct vm_area_struct *vma) > { > struct file *file = vma->vm_file; > struct mm_struct *mm = vma->vm_mm; > struct kioctx_table *table; > int i, res = -EINVAL; > > - if (flags & MREMAP_DONTUNMAP) > - return -EINVAL; > - > spin_lock(&mm->ioctx_lock); > rcu_read_lock(); > table = rcu_dereference(mm->ioctx_table); > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 77e64e3eac80..8c3729eb3e38 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -570,7 +570,7 @@ struct vm_operations_struct { > void (*close)(struct vm_area_struct * area); > /* Called any time before splitting to check if it's allowed */ > int (*may_split)(struct vm_area_struct *area, unsigned long addr); > - int (*mremap)(struct vm_area_struct *area, unsigned long flags); > + int (*mremap)(struct vm_area_struct *area); > /* > * Called by mprotect() to make driver-specific permission > * checks before mprotect() is finalised. The VMA must not > diff --git a/mm/mmap.c b/mm/mmap.c > index 3f287599a7a3..9d7651e4e1fe 100644 > --- a/mm/mmap.c > +++ b/mm/mmap.c > @@ -3403,14 +3403,10 @@ static const char *special_mapping_name(struct vm_area_struct *vma) > return ((struct vm_special_mapping *)vma->vm_private_data)->name; > } > > -static int special_mapping_mremap(struct vm_area_struct *new_vma, > - unsigned long flags) > +static int special_mapping_mremap(struct vm_area_struct *new_vma) > { > struct vm_special_mapping *sm = new_vma->vm_private_data; > > - if (flags & MREMAP_DONTUNMAP) > - return -EINVAL; > - > if (WARN_ON_ONCE(current->mm != new_vma->vm_mm)) > return -EFAULT; > > diff --git a/mm/mremap.c b/mm/mremap.c > index db5b8b28c2dd..d22629ff8f3c 100644 > --- a/mm/mremap.c > +++ b/mm/mremap.c > @@ -545,7 +545,7 @@ static unsigned long move_vma(struct vm_area_struct *vma, > if (moved_len < old_len) { > err = -ENOMEM; > } else if (vma->vm_ops && vma->vm_ops->mremap) { > - err = vma->vm_ops->mremap(new_vma, flags); > + err = vma->vm_ops->mremap(new_vma); > } > > if (unlikely(err)) { > -- > 2.31.0.rc2.261.g7f71774620-goog