From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759175Ab2I1Ugn (ORCPT ); Fri, 28 Sep 2012 16:36:43 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:63188 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965004Ab2I1Uad (ORCPT ); Fri, 28 Sep 2012 16:30:33 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Jason Wang , "Michael S. Tsirkin" , Ben Hutchings Subject: [ 168/218] macvtap: zerocopy: fix truesize underestimation Date: Fri, 28 Sep 2012 13:16:25 -0700 Message-Id: <20120928201520.790138548@linuxfoundation.org> X-Mailer: git-send-email 1.7.12.1.428.g652398a In-Reply-To: <20120928201501.208384923@linuxfoundation.org> References: <20120928201501.208384923@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jason Wang commit 4ef67ebedffa44ed9939b34708ac2fee06d2f65f upstream. As the skb fragment were pinned/built from user pages, we should account the page instead of length for truesize. Signed-off-by: Jason Wang Signed-off-by: Michael S. Tsirkin Cc: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- drivers/net/macvtap.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -520,6 +520,7 @@ static int zerocopy_sg_from_iovec(struct struct page *page[MAX_SKB_FRAGS]; int num_pages; unsigned long base; + unsigned long truesize; len = from->iov_len - offset; if (!len) { @@ -535,10 +536,11 @@ static int zerocopy_sg_from_iovec(struct if (num_pages != size) /* put_page is in skb free */ return -EFAULT; + truesize = size * PAGE_SIZE; skb->data_len += len; skb->len += len; - skb->truesize += len; - atomic_add(len, &skb->sk->sk_wmem_alloc); + skb->truesize += truesize; + atomic_add(truesize, &skb->sk->sk_wmem_alloc); while (len) { int off = base & ~PAGE_MASK; int size = min_t(int, len, PAGE_SIZE - off);