Message ID | 20231019113308.1133944-1-yoshihiro.shimoda.uh@renesas.com (mailing list archive) |
---|---|
State | Changes Requested |
Delegated to: | Netdev Maintainers |
Headers | show |
Series | [net,v2] ravb: Fix races between ravb_tx_timeout_work() and net related ops | expand |
Hello! On 10/19/23 2:33 PM, Yoshihiro Shimoda wrote: > Fix races between ravb_tx_timeout_work() and functions of net_device_ops > and ethtool_ops by using rtnl_trylock() and rtnl_unlock(). Note that > since ravb_close() is under the rtnl lock and calls cancel_work_sync(), > ravb_tx_timeout_work() should calls rtnl_trylock(). Otherwise, a deadlock > may happen in ravb_tx_timeout_work() like below: > > CPU0 CPU1 > ravb_tx_timeout() > schedule_work() > ... > __dev_close_many() > // Under rtnl lock > ravb_close() > cancel_work_sync() > // Waiting > ravb_tx_timeout_work() > rtnl_lock() > // This is possible to cause a deadlock > > Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru> [...] > diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c > index 0ef0b88b7145..300c1885e1e1 100644 > --- a/drivers/net/ethernet/renesas/ravb_main.c > +++ b/drivers/net/ethernet/renesas/ravb_main.c > @@ -1874,6 +1874,9 @@ static void ravb_tx_timeout_work(struct work_struct *work) > struct net_device *ndev = priv->ndev; > int error; > > + if (!rtnl_trylock()) > + return; I wonder if we should reschedule the work here... [...] MBR, Sergey
On Thu, Oct 19, 2023 at 08:33:08PM +0900, Yoshihiro Shimoda wrote: > Fix races between ravb_tx_timeout_work() and functions of net_device_ops > and ethtool_ops by using rtnl_trylock() and rtnl_unlock(). Note that > since ravb_close() is under the rtnl lock and calls cancel_work_sync(), > ravb_tx_timeout_work() should calls rtnl_trylock(). Otherwise, a deadlock > may happen in ravb_tx_timeout_work() like below: > > CPU0 CPU1 > ravb_tx_timeout() > schedule_work() > ... > __dev_close_many() > // Under rtnl lock > ravb_close() > cancel_work_sync() > // Waiting > ravb_tx_timeout_work() > rtnl_lock() > // This is possible to cause a deadlock > > Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Reviewed-by: Simon Horman <horms@kernel.org>
Hello, > From: Yoshihiro Shimoda, Sent: Thursday, October 19, 2023 8:33 PM > > Fix races between ravb_tx_timeout_work() and functions of net_device_ops > and ethtool_ops by using rtnl_trylock() and rtnl_unlock(). Note that > since ravb_close() is under the rtnl lock and calls cancel_work_sync(), > ravb_tx_timeout_work() should calls rtnl_trylock(). Otherwise, a deadlock > may happen in ravb_tx_timeout_work() like below: > > CPU0 CPU1 > ravb_tx_timeout() > schedule_work() > ... > __dev_close_many() > // Under rtnl lock > ravb_close() > cancel_work_sync() > // Waiting > ravb_tx_timeout_work() > rtnl_lock() > // This is possible to cause a deadlock > > Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Gentle ping. I confirmed that I could apply this patch on the latest net.git / main branch. Best regards, Yoshihiro Shimoda > --- > Changes from v1: <snip URL> > - Modify commit description. > - Use goto in a error path. > > drivers/net/ethernet/renesas/ravb_main.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c > index 0ef0b88b7145..300c1885e1e1 100644 > --- a/drivers/net/ethernet/renesas/ravb_main.c > +++ b/drivers/net/ethernet/renesas/ravb_main.c > @@ -1874,6 +1874,9 @@ static void ravb_tx_timeout_work(struct work_struct *work) > struct net_device *ndev = priv->ndev; > int error; > > + if (!rtnl_trylock()) > + return; > + > netif_tx_stop_all_queues(ndev); > > /* Stop PTP Clock driver */ > @@ -1907,7 +1910,7 @@ static void ravb_tx_timeout_work(struct work_struct *work) > */ > netdev_err(ndev, "%s: ravb_dmac_init() failed, error %d\n", > __func__, error); > - return; > + goto out_unlock; > } > ravb_emac_init(ndev); > > @@ -1917,6 +1920,9 @@ static void ravb_tx_timeout_work(struct work_struct *work) > ravb_ptp_init(ndev, priv->pdev); > > netif_tx_start_all_queues(ndev); > + > +out_unlock: > + rtnl_unlock(); > } > > /* Packet transmit function for Ethernet AVB */ > -- > 2.25.1
On Tue, 14 Nov 2023 08:52:29 +0000 Yoshihiro Shimoda wrote: > Gentle ping. I confirmed that I could apply this patch on > the latest net.git / main branch. At a glance the suggestion from Sergei makes sense. You need to reply to him.
> From: Jakub Kicinski, Sent: Wednesday, November 15, 2023 7:10 AM > > On Tue, 14 Nov 2023 08:52:29 +0000 Yoshihiro Shimoda wrote: > > Gentle ping. I confirmed that I could apply this patch on > > the latest net.git / main branch. > > At a glance the suggestion from Sergei makes sense. > You need to reply to him. Thank you for your reply. I completely overlooked his suggestion. I'll check it and reply to him. Best regards, Yoshihiro Shimoda
Hello Sergey, > From: Sergey Shtylyov, Sent: Thursday, October 19, 2023 9:36 PM > > Hello! > > On 10/19/23 2:33 PM, Yoshihiro Shimoda wrote: > > > Fix races between ravb_tx_timeout_work() and functions of net_device_ops > > and ethtool_ops by using rtnl_trylock() and rtnl_unlock(). Note that > > since ravb_close() is under the rtnl lock and calls cancel_work_sync(), > > ravb_tx_timeout_work() should calls rtnl_trylock(). Otherwise, a deadlock > > may happen in ravb_tx_timeout_work() like below: > > > > CPU0 CPU1 > > ravb_tx_timeout() > > schedule_work() > > ... > > __dev_close_many() > > // Under rtnl lock > > ravb_close() > > cancel_work_sync() > > // Waiting > > ravb_tx_timeout_work() > > rtnl_lock() > > // This is possible to cause a deadlock > > > > Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") > > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> > > Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru> Thank you for your review! > [...] > > diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c > > index 0ef0b88b7145..300c1885e1e1 100644 > > --- a/drivers/net/ethernet/renesas/ravb_main.c > > +++ b/drivers/net/ethernet/renesas/ravb_main.c > > @@ -1874,6 +1874,9 @@ static void ravb_tx_timeout_work(struct work_struct *work) > > struct net_device *ndev = priv->ndev; > > int error; > > > > + if (!rtnl_trylock()) > > + return; > > I wonder if we should reschedule the work here... I think so. But, it should reschedule the work if the netif is still running because Use-after-free issue happens again when cancel_work_sync() is calling. Also, I also think we should use schedule_delayed_work() instead. So, I'll submit such a patch as v3. Best regards, Yoshihiro Shimoda > [...] > > MBR, Sergey
On 11/15/23 5:09 AM, Yoshihiro Shimoda wrote: [...] >>> Fix races between ravb_tx_timeout_work() and functions of net_device_ops >>> and ethtool_ops by using rtnl_trylock() and rtnl_unlock(). Note that >>> since ravb_close() is under the rtnl lock and calls cancel_work_sync(), >>> ravb_tx_timeout_work() should calls rtnl_trylock(). Otherwise, a deadlock >>> may happen in ravb_tx_timeout_work() like below: >>> >>> CPU0 CPU1 >>> ravb_tx_timeout() >>> schedule_work() >>> ... >>> __dev_close_many() >>> // Under rtnl lock >>> ravb_close() >>> cancel_work_sync() >>> // Waiting >>> ravb_tx_timeout_work() >>> rtnl_lock() >>> // This is possible to cause a deadlock >>> >>> Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") >>> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> >> >> Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru> [...] >>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c >>> index 0ef0b88b7145..300c1885e1e1 100644 >>> --- a/drivers/net/ethernet/renesas/ravb_main.c >>> +++ b/drivers/net/ethernet/renesas/ravb_main.c >>> @@ -1874,6 +1874,9 @@ static void ravb_tx_timeout_work(struct work_struct *work) >>> struct net_device *ndev = priv->ndev; >>> int error; >>> >>> + if (!rtnl_trylock()) >>> + return; >> >> I wonder if we should reschedule the work here... > > I think so. But, it should reschedule the work if the netif is still running because > Use-after-free issue happens again when cancel_work_sync() is calling. Also, I also think > we should use schedule_delayed_work() instead. So, I'll submit such a patch as v3. I'm not really sure about that one. Note that cancel_work_sync() should work with the works requeueing themselves, the comments say... > Best regards, > Yoshihiro Shimoda [...] MBR, Sergey
Hello, > From: Sergey Shtylyov, Sent: Thursday, November 16, 2023 3:31 AM > > On 11/15/23 5:09 AM, Yoshihiro Shimoda wrote: > [...] > > >>> Fix races between ravb_tx_timeout_work() and functions of net_device_ops > >>> and ethtool_ops by using rtnl_trylock() and rtnl_unlock(). Note that > >>> since ravb_close() is under the rtnl lock and calls cancel_work_sync(), > >>> ravb_tx_timeout_work() should calls rtnl_trylock(). Otherwise, a deadlock > >>> may happen in ravb_tx_timeout_work() like below: > >>> > >>> CPU0 CPU1 > >>> ravb_tx_timeout() > >>> schedule_work() > >>> ... > >>> __dev_close_many() > >>> // Under rtnl lock > >>> ravb_close() > >>> cancel_work_sync() > >>> // Waiting > >>> ravb_tx_timeout_work() > >>> rtnl_lock() > >>> // This is possible to cause a deadlock > >>> > >>> Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") > >>> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> > >> > >> Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru> > > [...] > > >>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c > >>> index 0ef0b88b7145..300c1885e1e1 100644 > >>> --- a/drivers/net/ethernet/renesas/ravb_main.c > >>> +++ b/drivers/net/ethernet/renesas/ravb_main.c > >>> @@ -1874,6 +1874,9 @@ static void ravb_tx_timeout_work(struct work_struct *work) > >>> struct net_device *ndev = priv->ndev; > >>> int error; > >>> > >>> + if (!rtnl_trylock()) > >>> + return; > >> > >> I wonder if we should reschedule the work here... > > > > I think so. But, it should reschedule the work if the netif is still running because > > Use-after-free issue happens again when cancel_work_sync() is calling. Also, I also think > > we should use schedule_delayed_work() instead. So, I'll submit such a patch as v3. > > I'm not really sure about that one. Note that cancel_work_sync() should > work with the works requeueing themselves, the comments say... I'm sorry, I completely mistook to explain this... I should have said: It should not reschedule the work if the netif is not running because ~~~ ~~~ use-after-free issue happens again when cancel_work_sync() is called from ravb_remove(). ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Also, I completely misunderstood the behavior of cancel_{schedule_}work_sync(). In the function(s), since WORK_STRUCT_PENDING_BIT is set, schedule_{delayed_}work() will not schedule the work anymore. So, I'll drop a condition netif_running() from the ravb_tx_timeout_work(). Best regards, Yoshihiro Shimoda > > Best regards, > > Yoshihiro Shimoda > > [...] > > MBR, Sergey
On 11/16/23 5:15 AM, Yoshihiro Shimoda wrote: [...] >>>>> Fix races between ravb_tx_timeout_work() and functions of net_device_ops >>>>> and ethtool_ops by using rtnl_trylock() and rtnl_unlock(). Note that >>>>> since ravb_close() is under the rtnl lock and calls cancel_work_sync(), >>>>> ravb_tx_timeout_work() should calls rtnl_trylock(). Otherwise, a deadlock >>>>> may happen in ravb_tx_timeout_work() like below: >>>>> >>>>> CPU0 CPU1 >>>>> ravb_tx_timeout() >>>>> schedule_work() >>>>> ... >>>>> __dev_close_many() >>>>> // Under rtnl lock >>>>> ravb_close() >>>>> cancel_work_sync() >>>>> // Waiting >>>>> ravb_tx_timeout_work() >>>>> rtnl_lock() >>>>> // This is possible to cause a deadlock >>>>> >>>>> Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") >>>>> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> >>>> >>>> Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru> >> >> [...] >> >>>>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c >>>>> index 0ef0b88b7145..300c1885e1e1 100644 >>>>> --- a/drivers/net/ethernet/renesas/ravb_main.c >>>>> +++ b/drivers/net/ethernet/renesas/ravb_main.c >>>>> @@ -1874,6 +1874,9 @@ static void ravb_tx_timeout_work(struct work_struct *work) >>>>> struct net_device *ndev = priv->ndev; >>>>> int error; >>>>> >>>>> + if (!rtnl_trylock()) >>>>> + return; >>>> >>>> I wonder if we should reschedule the work here... >>> >>> I think so. But, it should reschedule the work if the netif is still running because >>> Use-after-free issue happens again when cancel_work_sync() is calling. Also, I also think >>> we should use schedule_delayed_work() instead. So, I'll submit such a patch as v3. >> >> I'm not really sure about that one. Note that cancel_work_sync() should >> work with the works requeueing themselves, the comments say... > > I'm sorry, I completely mistook to explain this... I should have said: Don't worry, my uncertainty was about using the "delayed" flavor of the works. :-) > It should not reschedule the work if the netif is not running because > ~~~ ~~~ > use-after-free issue happens again when cancel_work_sync() is called from ravb_remove(). > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Well, it's called from ravb_close() -- which is called by the networking core when unregister_netdev() is called bt ravb_remove()... > Also, I completely misunderstood the behavior of cancel_{schedule_}work_sync(). cancel_{delayed_}work_sync(), you meant... > In the function(s), since WORK_STRUCT_PENDING_BIT is set, schedule_{delayed_}work() > will not schedule the work anymore. So, I'll drop a condition netif_running() > from the ravb_tx_timeout_work(). Hm, this caused me to rummage in the work queue code for more time than I could afford... still not sure what you meant... :-/ > Best regards, > Yoshihiro Shimoda [...] MBR, Sergey
> From: Sergey Shtylyov, Sent: Friday, November 17, 2023 3:12 AM > > On 11/16/23 5:15 AM, Yoshihiro Shimoda wrote: > [...] > > >>>>> Fix races between ravb_tx_timeout_work() and functions of net_device_ops > >>>>> and ethtool_ops by using rtnl_trylock() and rtnl_unlock(). Note that > >>>>> since ravb_close() is under the rtnl lock and calls cancel_work_sync(), > >>>>> ravb_tx_timeout_work() should calls rtnl_trylock(). Otherwise, a deadlock > >>>>> may happen in ravb_tx_timeout_work() like below: > >>>>> > >>>>> CPU0 CPU1 > >>>>> ravb_tx_timeout() > >>>>> schedule_work() > >>>>> ... > >>>>> __dev_close_many() > >>>>> // Under rtnl lock > >>>>> ravb_close() > >>>>> cancel_work_sync() > >>>>> // Waiting > >>>>> ravb_tx_timeout_work() > >>>>> rtnl_lock() > >>>>> // This is possible to cause a deadlock > >>>>> > >>>>> Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") > >>>>> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> > >>>> > >>>> Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru> > >> > >> [...] > >> > >>>>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c > >>>>> index 0ef0b88b7145..300c1885e1e1 100644 > >>>>> --- a/drivers/net/ethernet/renesas/ravb_main.c > >>>>> +++ b/drivers/net/ethernet/renesas/ravb_main.c > >>>>> @@ -1874,6 +1874,9 @@ static void ravb_tx_timeout_work(struct work_struct *work) > >>>>> struct net_device *ndev = priv->ndev; > >>>>> int error; > >>>>> > >>>>> + if (!rtnl_trylock()) > >>>>> + return; > >>>> > >>>> I wonder if we should reschedule the work here... > >>> > >>> I think so. But, it should reschedule the work if the netif is still running because > >>> Use-after-free issue happens again when cancel_work_sync() is calling. Also, I also think > >>> we should use schedule_delayed_work() instead. So, I'll submit such a patch as v3. > >> > >> I'm not really sure about that one. Note that cancel_work_sync() should > >> work with the works requeueing themselves, the comments say... > > > > I'm sorry, I completely mistook to explain this... I should have said: > > Don't worry, my uncertainty was about using the "delayed" flavor of > the works. :-) > > > It should not reschedule the work if the netif is not running because > > ~~~ ~~~ > > use-after-free issue happens again when cancel_work_sync() is called from ravb_remove(). > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Well, it's called from ravb_close() -- which is called by the networking > core when unregister_netdev() is called bt ravb_remove()... You're correct. I'm sorry for my lack explanation again... > > Also, I completely misunderstood the behavior of cancel_{schedule_}work_sync(). > > cancel_{delayed_}work_sync(), you meant... Yes... > > In the function(s), since WORK_STRUCT_PENDING_BIT is set, schedule_{delayed_}work() > > will not schedule the work anymore. So, I'll drop a condition netif_running() > > from the ravb_tx_timeout_work(). > > Hm, this caused me to rummage in the work queue code for more time than > I could afford... still not sure what you meant... :-/ I'm sorry for bothering you about this topic... In the v3 patch, the rescheduling code was: --- + if (!rtnl_trylock()) { + if (netif_running(ndev)) + schedule_delayed_work(&priv->work, msecs_to_jiffies(10)); + return; + } --- However, we can implement this like the following: --- + if (!rtnl_trylock()) { + schedule_delayed_work(&priv->work, msecs_to_jiffies(10)); + return; + } --- The schedule_{delayed}_work() will not be queued after cancel_{delayed_}work_sync() was called, because WORK_STRUCT_PENDING_BIT was set in cancel_{delayed_}work_sync() like the following: --- cancel_work_sync() -> __cancel_work_timer() -> try_to_grab_pending() -> if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, ...) schedule_work() -> queue_work() -> queue_work_on() -> if (test_and_set_bit(WORK_STRUCT_PENDING_BIT, ...) -> __queue_work() --- Best regards, Yoshihiro Shimoda > > Best regards, > > Yoshihiro Shimoda > [...] > > MBR, Sergey
Hello! Sorry for the late reply -- the damn dozen of the AVB patches fell on me this Monday... :-/ On 11/17/23 3:07 AM, Yoshihiro Shimoda wrote: [...] >>> In the function(s), since WORK_STRUCT_PENDING_BIT is set, schedule_{delayed_}work() >>> will not schedule the work anymore. So, I'll drop a condition netif_running() >>> from the ravb_tx_timeout_work(). >> >> Hm, this caused me to rummage in the work queue code for more time than >> I could afford... still not sure what you meant... :-/ > > I'm sorry for bothering you about this topic... > In the v3 patch, the rescheduling code was: > --- > + if (!rtnl_trylock()) { > + if (netif_running(ndev)) > + schedule_delayed_work(&priv->work, msecs_to_jiffies(10)); > + return; > + } > --- > > However, we can implement this like the following: > --- > + if (!rtnl_trylock()) { > + schedule_delayed_work(&priv->work, msecs_to_jiffies(10)); > + return; > + } > --- > > The schedule_{delayed}_work() will not be queued after cancel_{delayed_}work_sync() > was called, because WORK_STRUCT_PENDING_BIT was set in cancel_{delayed_}work_sync() > like the following: > --- > cancel_work_sync() > -> __cancel_work_timer() > -> try_to_grab_pending() > -> if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, ...) > > schedule_work() > -> queue_work() > -> queue_work_on() > -> if (test_and_set_bit(WORK_STRUCT_PENDING_BIT, ...) You seem to have lost ! here. :-) > -> __queue_work() Ah! Now it makes perfect sense. Sorry, this somehow evaded me... :-/ > --- > > Best regards, > Yoshihiro Shimoda [...] MBR, Sergey
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index 0ef0b88b7145..300c1885e1e1 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -1874,6 +1874,9 @@ static void ravb_tx_timeout_work(struct work_struct *work) struct net_device *ndev = priv->ndev; int error; + if (!rtnl_trylock()) + return; + netif_tx_stop_all_queues(ndev); /* Stop PTP Clock driver */ @@ -1907,7 +1910,7 @@ static void ravb_tx_timeout_work(struct work_struct *work) */ netdev_err(ndev, "%s: ravb_dmac_init() failed, error %d\n", __func__, error); - return; + goto out_unlock; } ravb_emac_init(ndev); @@ -1917,6 +1920,9 @@ static void ravb_tx_timeout_work(struct work_struct *work) ravb_ptp_init(ndev, priv->pdev); netif_tx_start_all_queues(ndev); + +out_unlock: + rtnl_unlock(); } /* Packet transmit function for Ethernet AVB */
Fix races between ravb_tx_timeout_work() and functions of net_device_ops and ethtool_ops by using rtnl_trylock() and rtnl_unlock(). Note that since ravb_close() is under the rtnl lock and calls cancel_work_sync(), ravb_tx_timeout_work() should calls rtnl_trylock(). Otherwise, a deadlock may happen in ravb_tx_timeout_work() like below: CPU0 CPU1 ravb_tx_timeout() schedule_work() ... __dev_close_many() // Under rtnl lock ravb_close() cancel_work_sync() // Waiting ravb_tx_timeout_work() rtnl_lock() // This is possible to cause a deadlock Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> --- Changes from v1: https://lore.kernel.org/all/20231017085341.813335-1-yoshihiro.shimoda.uh@renesas.com/ - Modify commit description. - Use goto in a error path. drivers/net/ethernet/renesas/ravb_main.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)