Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932642AbdGCNnb (ORCPT ); Mon, 3 Jul 2017 09:43:31 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:36326 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932340AbdGCNn1 (ORCPT ); Mon, 3 Jul 2017 09:43:27 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , Claudiu Manoil , Claudiu Manoil , "David S. Miller" , Sasha Levin Subject: [PATCH 4.9 079/172] gianfar: Do not reuse pages from emergency reserve Date: Mon, 3 Jul 2017 15:34:19 +0200 Message-Id: <20170703133417.987611993@linuxfoundation.org> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20170703133414.260777365@linuxfoundation.org> References: <20170703133414.260777365@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1381 Lines: 41 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 69fed99baac186013840ced3524562841296034f ] A driver using dev_alloc_page() must not reuse a page that had to use emergency memory reserve. Otherwise all packets using this page will be immediately dropped, unless for very specific sockets having SOCK_MEMALLOC bit set. This issue might be hard to debug, because only a fraction of the RX ring buffer would suffer from drops. Fixes: 75354148ce69 ("gianfar: Add paged allocation and Rx S/G") Signed-off-by: Eric Dumazet Cc: Claudiu Manoil Acked-by: Claudiu Manoil Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/freescale/gianfar.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/net/ethernet/freescale/gianfar.c +++ b/drivers/net/ethernet/freescale/gianfar.c @@ -2951,7 +2951,7 @@ static bool gfar_add_rx_frag(struct gfar } /* try reuse page */ - if (unlikely(page_count(page) != 1)) + if (unlikely(page_count(page) != 1 || page_is_pfmemalloc(page))) return false; /* change offset to the other half */