From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Neftin, Sasha" Subject: Re: [Intel-wired-lan] [PATCH v2] e1000e: free IRQ regardless of __E1000_DOWN Date: Thu, 10 Nov 2016 08:19:28 +0200 Message-ID: <42e53bc2-0361-e7b7-1093-4e095aa56955@intel.com> References: <1478727681-16505-1-git-send-email-tbaicar@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit To: Tyler Baicar , jeffrey.t.kirsher@intel.com, intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, okaya@codeaurora.org, timur@codeaurora.org Return-path: In-Reply-To: <1478727681-16505-1-git-send-email-tbaicar@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 11/9/2016 11:41 PM, Tyler Baicar wrote: > Move IRQ free code so that it will happen regardless of the > __E1000_DOWN bit. Currently the e1000e driver only releases its IRQ > if the __E1000_DOWN bit is cleared. This is not sufficient because > it is possible for __E1000_DOWN to be set without releasing the IRQ. > In such a situation, we will hit a kernel bug later in e1000_remove > because the IRQ still has action since it was never freed. A > secondary bus reset can cause this case to happen. > > Signed-off-by: Tyler Baicar > --- > drivers/net/ethernet/intel/e1000e/netdev.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c > index 7017281..36cfcb0 100644 > --- a/drivers/net/ethernet/intel/e1000e/netdev.c > +++ b/drivers/net/ethernet/intel/e1000e/netdev.c > @@ -4679,12 +4679,13 @@ int e1000e_close(struct net_device *netdev) > > if (!test_bit(__E1000_DOWN, &adapter->state)) { > e1000e_down(adapter, true); > - e1000_free_irq(adapter); > > /* Link status message must follow this format */ > pr_info("%s NIC Link is Down\n", adapter->netdev->name); > } > > + e1000_free_irq(adapter); > + > napi_disable(&adapter->napi); > > e1000e_free_tx_resources(adapter->tx_ring); > I would like not recommend insert this change. This change related driver state machine, we afraid from lot of synchronization problem and issues. We need keep e1000_free_irq in loop and check for 'test_bit' ready. Another point, does before execute secondary bus reset your SW back up pcie configuration space as properly? Sasha