From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Belous Subject: Re: [PATCH] aquantia: Fix "ethtool -S" crash when adapter down. Date: Thu, 4 May 2017 20:09:56 +0300 Message-ID: References: <90666578f043b366313ddd90ffad86de42d890f2.1493914743.git.pavel.belous@aquantia.com> <0babf800-080c-96e0-4dbb-8d3fca3fb784@gmx.de> <20170504.125113.569969253752966231.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, darcari@redhat.com To: David Miller , LinoSanfilippo@gmx.de Return-path: Received: from mail-sn1nam02on0060.outbound.protection.outlook.com ([104.47.36.60]:33907 "EHLO NAM02-SN1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751492AbdEDRKM (ORCPT ); Thu, 4 May 2017 13:10:12 -0400 In-Reply-To: <20170504.125113.569969253752966231.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-ID: On 04.05.2017 19:51, David Miller wrote: > From: Lino Sanfilippo > Date: Thu, 4 May 2017 18:48:12 +0200 > >> Hi Pavel, >> >> On 04.05.2017 18:33, Pavel Belous wrote: >>> From: Pavel Belous >>> >>> This patch fixes the crash that happens when driver tries to collect statistics >>> from already released "aq_vec" object. >>> >>> Fixes: 97bde5c4f909 ("net: ethernet: aquantia: Support for NIC-specific code") >>> Signed-off-by: Pavel Belous >>> --- >>> drivers/net/ethernet/aquantia/atlantic/aq_nic.c | 3 ++- >>> 1 file changed, 2 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c >>> index cdb0299..3a32573 100644 >>> --- a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c >>> +++ b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c >>> @@ -755,7 +755,7 @@ void aq_nic_get_stats(struct aq_nic_s *self, u64 *data) >>> count = 0U; >>> >>> for (i = 0U, aq_vec = self->aq_vec[0]; >>> - self->aq_vecs > i; ++i, aq_vec = self->aq_vec[i]) { >>> + aq_vec && self->aq_vecs > i; ++i, aq_vec = self->aq_vec[i]) { >>> data += count; >>> aq_vec_get_sw_stats(aq_vec, data, &count); >>> } >>> @@ -961,6 +961,7 @@ void aq_nic_free_hot_resources(struct aq_nic_s *self) >>> for (i = AQ_DIMOF(self->aq_vec); i--;) { >>> if (self->aq_vec[i]) >>> aq_vec_free(self->aq_vec[i]); >>> + self->aq_vec[i] = NULL; >>> } >>> >>> err_exit:; >>> >> >> if the driver does not support statistics when the interface is down, would not it be clearer >> to check if netif_running() in get_stats() instead? > > Yes, much cleaner. > > Much better would be to have a cached software copy so that statistics > can be reported regardless of whether the device is down or not. > Thank you. I will think about how to do it better. Regards, Pavel