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 64389C61DA4 for ; Fri, 3 Feb 2023 08:37:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231871AbjBCIhF (ORCPT ); Fri, 3 Feb 2023 03:37:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42874 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230020AbjBCIhD (ORCPT ); Fri, 3 Feb 2023 03:37:03 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E43A14B8B2 for ; Fri, 3 Feb 2023 00:36:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1675413376; 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=4SgfxfX+R40emIUXjC0IKRTnZn8Kx7fI1FhxMp6y+tk=; b=Q7JDJpdG/3r7bwguhrXrKooTJizuh0gUty06fGVe0B1xauRjdVoD+Y8YyU/5/MPvzK39hB IyGe/N+5onyi6iKrP3fSdes1PSh3Jhldn+9R32jqiEK8D2pb46KOpJyHvBeoUgCW3yRCPf u/48YT9Fw6ZJQ36iSAxq/eonqR1T72c= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-241-UC8RY2tXMU2MA0Ie6u6v0g-1; Fri, 03 Feb 2023 03:36:12 -0500 X-MC-Unique: UC8RY2tXMU2MA0Ie6u6v0g-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 5B68D101A55E; Fri, 3 Feb 2023 08:36:12 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.97]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7C25A492C14; Fri, 3 Feb 2023 08:36:11 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <72029a93-1150-1994-916f-b15ef0befd49@nvidia.com> References: <72029a93-1150-1994-916f-b15ef0befd49@nvidia.com> <000000000000b0b3c005f3a09383@google.com> <822863.1675327935@warthog.procyon.org.uk> <1265629.1675350909@warthog.procyon.org.uk> To: John Hubbard Cc: dhowells@redhat.com, David Hildenbrand , syzbot , hch@lst.de, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] general protection fault in skb_dequeue (3) MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <1723029.1675413370.1@warthog.procyon.org.uk> Date: Fri, 03 Feb 2023 08:36:10 +0000 Message-ID: <1723030.1675413370@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Interestingly, the problem also goes away if the ftruncate is removed from the test program. Are pages ever spliced from the pipe directly into the pagecache on both xfs and ext4? I'm not sure whether that could happen as the test seeks 2048 bytes in before doing the sendfile(). David