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=-16.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 E141CC43461 for ; Mon, 3 May 2021 08:23:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 65F4A61221 for ; Mon, 3 May 2021 08:23:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232972AbhECIYt (ORCPT ); Mon, 3 May 2021 04:24:49 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:41908 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232959AbhECIYs (ORCPT ); Mon, 3 May 2021 04:24:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1620030235; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=bPRJDN7+PYmkwRc18YCW4pqF1oNECdl7EEdKg52HHCc=; b=fZOskuy4AziUojSmYmC8d9BYMWW0aNr5cQRHwhWwo9A0j4gHATn8awGPxiqiJ9s6HdDOEP eRUSpAM/yB//6wXWoyqIjtUcJSmCkeKCz63c6FM28v5OnnTzEfAZQR3AqhpcxjiIQqjhtS P4//sRoOoY7Kx0OJYWxf244IMCexSiw= Received: from mail-wr1-f70.google.com (mail-wr1-f70.google.com [209.85.221.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-315-Om1Kx7gMOEO-CzY_P7baTw-1; Mon, 03 May 2021 04:23:52 -0400 X-MC-Unique: Om1Kx7gMOEO-CzY_P7baTw-1 Received: by mail-wr1-f70.google.com with SMTP id x10-20020adfc18a0000b029010d83c83f2aso3486290wre.8 for ; Mon, 03 May 2021 01:23:51 -0700 (PDT) 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:message-id:references :mime-version:content-disposition:in-reply-to; bh=bPRJDN7+PYmkwRc18YCW4pqF1oNECdl7EEdKg52HHCc=; b=kMlEblwE0We7lGKXdQ6NNtf3Q6Vh7xiUR5TixPlme7x4XD6iz72Wu2iyQd3atYYnCb 7xVGnQ69CLTIH0dQhsKfo+pvaEpjucxd/cKhFJpqNYCNrqt5ElhBnVxNJGPPA0OiO29e 7PMCtW13uHRv2WaFu/6yUDWkirNoi/BHO/iHa2Y/ScPlaGVNUZjOjYCv6ILcmY4KcAf1 Hun7gpYe0Y3N0cSsoBkeXSvO++6JPB33zoizO0Vg9Tnx80dg+zWVW60rAsFcZi2+vmbG C2puszrM3CmStd2sF8zcHsjTKEN5B2ohY6huMd5wvc2rP5Q/KgtE3d+vSx5nJ/xAxthD e4TA== X-Gm-Message-State: AOAM5337ZQTCRrLXpPaWq5gmuC2QpxndK6tmXaYmAvIz1WrDbIos7DAe fS1FJqKmui7bPXcjrJhz2XzU4dsNlQ1Y5ak94k92E/7s1MS6uEommz+MfdVBOMPCvC7D6lThOKh G4XtVtRUCNa2R7KPLaGSTkgU1Hw== X-Received: by 2002:a05:6000:184a:: with SMTP id c10mr23619886wri.237.1620030231115; Mon, 03 May 2021 01:23:51 -0700 (PDT) X-Google-Smtp-Source: ABdhPJziGxRW4ZxIY4FY2qg1KRAZv5We9hL1OQjj2LLIG4bdcedtb0gAbjIZDrDWQnD40SLdnCFbag== X-Received: by 2002:a05:6000:184a:: with SMTP id c10mr23619863wri.237.1620030230987; Mon, 03 May 2021 01:23:50 -0700 (PDT) Received: from redhat.com ([2a10:800a:cdef:0:114d:2085:61e4:7b41]) by smtp.gmail.com with ESMTPSA id n22sm8177060wmo.12.2021.05.03.01.23.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 03 May 2021 01:23:50 -0700 (PDT) Date: Mon, 3 May 2021 04:23:47 -0400 From: "Michael S. Tsirkin" To: David Hildenbrand Cc: linux-kernel@vger.kernel.org, Andrew Morton , Jason Wang , Alexey Dobriyan , Mike Rapoport , "Matthew Wilcox (Oracle)" , Oscar Salvador , Michal Hocko , Roman Gushchin , Alex Shi , Steven Price , Mike Kravetz , Aili Yao , Jiri Bohac , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Wei Liu , Naoya Horiguchi , linux-hyperv@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v1 6/7] virtio-mem: use page_offline_(start|end) when setting PageOffline() Message-ID: <20210503042220-mutt-send-email-mst@kernel.org> References: <20210429122519.15183-1-david@redhat.com> <20210429122519.15183-7-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210429122519.15183-7-david@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Thu, Apr 29, 2021 at 02:25:18PM +0200, David Hildenbrand wrote: > Let's properly use page_offline_(start|end) to synchronize setting > PageOffline(), so we won't have valid page access to unplugged memory > regions from /proc/kcore. > > Signed-off-by: David Hildenbrand the patch looks good to me as such Acked-by: Michael S. Tsirkin Feel free to merge with rest of patcgset - it seems to mostly live in the fs/mm space. IF you respin, maybe add the explanation you sent in response to Mike's comments in the commit log. > --- > drivers/virtio/virtio_mem.c | 2 ++ > mm/util.c | 2 ++ > 2 files changed, 4 insertions(+) > > diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c > index 10ec60d81e84..dc2a2e2b2ff8 100644 > --- a/drivers/virtio/virtio_mem.c > +++ b/drivers/virtio/virtio_mem.c > @@ -1065,6 +1065,7 @@ static int virtio_mem_memory_notifier_cb(struct notifier_block *nb, > static void virtio_mem_set_fake_offline(unsigned long pfn, > unsigned long nr_pages, bool onlined) > { > + page_offline_begin(); > for (; nr_pages--; pfn++) { > struct page *page = pfn_to_page(pfn); > > @@ -1075,6 +1076,7 @@ static void virtio_mem_set_fake_offline(unsigned long pfn, > ClearPageReserved(page); > } > } > + page_offline_end(); > } > > /* > diff --git a/mm/util.c b/mm/util.c > index 95395d4e4209..d0e357bd65e6 100644 > --- a/mm/util.c > +++ b/mm/util.c > @@ -1046,8 +1046,10 @@ void page_offline_begin(void) > { > down_write(&page_offline_rwsem); > } > +EXPORT_SYMBOL(page_offline_begin); > > void page_offline_end(void) > { > up_write(&page_offline_rwsem); > } > +EXPORT_SYMBOL(page_offline_end); > -- > 2.30.2