From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F3D1A46BD for ; Sat, 17 Jun 2023 06:43:26 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9A765297A for ; Fri, 16 Jun 2023 23:43:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1686984204; 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=KT3z5MBsLMZkLkeo6Bj0bSQulysSCuM486H4EH/KXBo=; b=ajE6gF9RkiMqM/z4XUUS99hCMIwG5azliuEmiqHCm0h5OAMMRD0V0avFteUE8kStmYz20+ FDQB1BS+pI9P2jxqngkLuQp95TDt6IG5sRKgiqbm6Iukqdaup31An6yGPHQWGjR2M5OIoz 4IRHiT7gXLNc2Fg+CdYIN0KZQez9RUk= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-114-ZW6hiUcWM0G5bKLmfNojwA-1; Sat, 17 Jun 2023 02:43:18 -0400 X-MC-Unique: ZW6hiUcWM0G5bKLmfNojwA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id EF5773C00086; Sat, 17 Jun 2023 06:43:17 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.42.28.51]) by smtp.corp.redhat.com (Postfix) with ESMTP id 12E712166B25; Sat, 17 Jun 2023 06:43:15 +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: References: <20230616161301.622169-1-dhowells@redhat.com> <20230616161301.622169-2-dhowells@redhat.com> To: Simon Horman Cc: dhowells@redhat.com, netdev@vger.kernel.org, Alexander Duyck , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Willem de Bruijn , David Ahern , Matthew Wilcox , Jens Axboe , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Menglong Dong Subject: Re: [PATCH net-next 01/17] net: Copy slab data for sendmsg(MSG_SPLICE_PAGES) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <708509.1686984195.1@warthog.procyon.org.uk> Date: Sat, 17 Jun 2023 07:43:15 +0100 Message-ID: <708510.1686984195@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H5,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE, T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Simon Horman wrote: > > + cache = get_cpu_ptr(&skb_splice_frag_cache); ... > > + put_cpu_ptr(skb_splice_frag_cache); > > Hi David, > > I don't think it makes any difference at run-time. > But to keep Sparse happy, perhaps this ought to be put_cpu_var() Actually, the problem is a missing "&". I think I should use put_cpu_ptr() to match get_cpu_ptr(). It doesn't crash because the argument is ignored. David