From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: Re: [PATCH] net: arc_emac: fix arc_emac_rx() error paths Date: Tue, 19 Dec 2017 10:33:35 -0800 Message-ID: <9170e5bb-4765-a4dd-9d85-e44791877ea1@gmail.com> References: <1513358406-32503-1-git-send-email-al.kochet@gmail.com> <20171219.102254.1959679351283055093.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, edumazet@google.com To: Alexander Kochetkov , David Miller Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 12/19/2017 07:49 AM, Alexander Kochetkov wrote: > >> 19 дек. 2017 г., в 18:22, David Miller написал(а): >> >> From: Alexander Kochetkov >> Date: Fri, 15 Dec 2017 20:20:06 +0300 >> >>> arc_emac_rx() has some issues found by code review. >>> >>> In case netdev_alloc_skb_ip_align() or dma_map_single() failure >>> rx fifo entry will not be returned to EMAC. >>> >>> In case dma_map_single() failure previously allocated skb became >>> lost to driver. At the same time address of newly allocated skb >>> will not be provided to EMAC. >>> >>> Signed-off-by: Alexander Kochetkov >> >> This patch adds quite a few bugs, here is one which shows this is not >> functionally tested: > > May be I don’t understand correctly, but I don’t see bug here. > > Wrong dma mapping usage should immediately manifest itself (kernel > instability, koops and so on). The patch was tested on rk3188 and work fine for me. > Also I did simulations of netdev_alloc_skb_ip_align() and dma_map_single() > faults and can confirm that new error handling work. > > Could someone else with ARC EMAC test the patch? I would be very grateful for the help. > Florian or Eric, can you test it on your hardware? I don't actually have access to this hardware, the only change I did to this driver was to use a standard Device Tree property :) -- Florian