diff mbox series

[net,v3] ethernet: s2io: don't call dev_kfree_skb() under spin_lock_irqsave()

Message ID 20221208092411.1961448-1-yangyingliang@huawei.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series [net,v3] ethernet: s2io: don't call dev_kfree_skb() under spin_lock_irqsave() | expand

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netdev/tree_selection success Clearly marked for net
netdev/fixes_present success Fixes tag present in non-next series
netdev/subject_prefix success Link
netdev/cover_letter success Single patches do not need cover letters
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 17 this patch: 17
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 1 this patch: 1
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 8 lines checked
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netdev/source_inline success Was 0 now: 0

Commit Message

Yang Yingliang Dec. 8, 2022, 9:24 a.m. UTC
The dev_kfree_skb() is defined as consume_skb(), and it is not allowed
to call consume_skb() from hardware interrupt context or with interrupts
being disabled. So replace dev_kfree_skb() with dev_consume_skb_irq()
under spin_lock_irqsave().

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
---
v2 -> v3:
  Update commit message.

v1 -> v2:
  Add fix tag.
---
 drivers/net/ethernet/neterion/s2io.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Leon Romanovsky Dec. 8, 2022, 9:43 a.m. UTC | #1
On Thu, Dec 08, 2022 at 05:24:11PM +0800, Yang Yingliang wrote:
> The dev_kfree_skb() is defined as consume_skb(), and it is not allowed
> to call consume_skb() from hardware interrupt context or with interrupts
> being disabled. So replace dev_kfree_skb() with dev_consume_skb_irq()
> under spin_lock_irqsave().

While dev_kfree_skb and consume_skb are the same, the dev_kfree_skb_irq
and dev_consume_skb_irq are not. You can't blindly replace
dev_kfree_skb with dev_consume_skb_irq. You should check every place, analyze
and document why specific option was chosen.

  3791 static inline void dev_kfree_skb_irq(struct sk_buff *skb)
  3792 {
  3793         __dev_kfree_skb_irq(skb, SKB_REASON_DROPPED);
  3794 }
  3795
  3796 static inline void dev_consume_skb_irq(struct sk_buff *skb)
  3797 {
  3798         __dev_kfree_skb_irq(skb, SKB_REASON_CONSUMED);
  3799 }

Thanks


> 
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
> ---
> v2 -> v3:
>   Update commit message.
> 
> v1 -> v2:
>   Add fix tag.
> ---
>  drivers/net/ethernet/neterion/s2io.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/neterion/s2io.c b/drivers/net/ethernet/neterion/s2io.c
> index 1d3c4474b7cb..a83d61d45936 100644
> --- a/drivers/net/ethernet/neterion/s2io.c
> +++ b/drivers/net/ethernet/neterion/s2io.c
> @@ -2386,7 +2386,7 @@ static void free_tx_buffers(struct s2io_nic *nic)
>  			skb = s2io_txdl_getskb(&mac_control->fifos[i], txdp, j);
>  			if (skb) {
>  				swstats->mem_freed += skb->truesize;
> -				dev_kfree_skb(skb);
> +				dev_consume_skb_irq(skb);
>  				cnt++;
>  			}
>  		}
> -- 
> 2.25.1
>
Yang Yingliang Dec. 8, 2022, 10:31 a.m. UTC | #2
On 2022/12/8 17:43, Leon Romanovsky wrote:
> On Thu, Dec 08, 2022 at 05:24:11PM +0800, Yang Yingliang wrote:
>> The dev_kfree_skb() is defined as consume_skb(), and it is not allowed
>> to call consume_skb() from hardware interrupt context or with interrupts
>> being disabled. So replace dev_kfree_skb() with dev_consume_skb_irq()
>> under spin_lock_irqsave().
> While dev_kfree_skb and consume_skb are the same, the dev_kfree_skb_irq
> and dev_consume_skb_irq are not. You can't blindly replace
> dev_kfree_skb with dev_consume_skb_irq. You should check every place, analyze
> and document why specific option was chosen.
While calling dev_kfree_skb(consume_skb), the SKB will not be marked as 
dropped,
to keep the same meaning, so replace it with dev_consume_skb_irq()

Thanks,
Yang
>
>    3791 static inline void dev_kfree_skb_irq(struct sk_buff *skb)
>    3792 {
>    3793         __dev_kfree_skb_irq(skb, SKB_REASON_DROPPED);
>    3794 }
>    3795
>    3796 static inline void dev_consume_skb_irq(struct sk_buff *skb)
>    3797 {
>    3798         __dev_kfree_skb_irq(skb, SKB_REASON_CONSUMED);
>    3799 }
>
> Thanks
>
>
>> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
>> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
>> ---
>> v2 -> v3:
>>    Update commit message.
>>
>> v1 -> v2:
>>    Add fix tag.
>> ---
>>   drivers/net/ethernet/neterion/s2io.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/ethernet/neterion/s2io.c b/drivers/net/ethernet/neterion/s2io.c
>> index 1d3c4474b7cb..a83d61d45936 100644
>> --- a/drivers/net/ethernet/neterion/s2io.c
>> +++ b/drivers/net/ethernet/neterion/s2io.c
>> @@ -2386,7 +2386,7 @@ static void free_tx_buffers(struct s2io_nic *nic)
>>   			skb = s2io_txdl_getskb(&mac_control->fifos[i], txdp, j);
>>   			if (skb) {
>>   				swstats->mem_freed += skb->truesize;
>> -				dev_kfree_skb(skb);
>> +				dev_consume_skb_irq(skb);
>>   				cnt++;
>>   			}
>>   		}
>> -- 
>> 2.25.1
>>
> .
Leon Romanovsky Dec. 8, 2022, 10:47 a.m. UTC | #3
On Thu, Dec 08, 2022 at 06:31:00PM +0800, Yang Yingliang wrote:
> 
> On 2022/12/8 17:43, Leon Romanovsky wrote:
> > On Thu, Dec 08, 2022 at 05:24:11PM +0800, Yang Yingliang wrote:
> > > The dev_kfree_skb() is defined as consume_skb(), and it is not allowed
> > > to call consume_skb() from hardware interrupt context or with interrupts
> > > being disabled. So replace dev_kfree_skb() with dev_consume_skb_irq()
> > > under spin_lock_irqsave().
> > While dev_kfree_skb and consume_skb are the same, the dev_kfree_skb_irq
> > and dev_consume_skb_irq are not. You can't blindly replace
> > dev_kfree_skb with dev_consume_skb_irq. You should check every place, analyze
> > and document why specific option was chosen.
> While calling dev_kfree_skb(consume_skb), the SKB will not be marked as
> dropped,
> to keep the same meaning, so replace it with dev_consume_skb_irq()

This annotation code is relatively new (from 2013), while you are
changing code from pre-git era (<2005). 

Thanks

> 
> Thanks,
> Yang
> > 
> >    3791 static inline void dev_kfree_skb_irq(struct sk_buff *skb)
> >    3792 {
> >    3793         __dev_kfree_skb_irq(skb, SKB_REASON_DROPPED);
> >    3794 }
> >    3795
> >    3796 static inline void dev_consume_skb_irq(struct sk_buff *skb)
> >    3797 {
> >    3798         __dev_kfree_skb_irq(skb, SKB_REASON_CONSUMED);
> >    3799 }
> > 
> > Thanks
> > 
> > 
> > > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> > > Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
> > > ---
> > > v2 -> v3:
> > >    Update commit message.
> > > 
> > > v1 -> v2:
> > >    Add fix tag.
> > > ---
> > >   drivers/net/ethernet/neterion/s2io.c | 2 +-
> > >   1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/net/ethernet/neterion/s2io.c b/drivers/net/ethernet/neterion/s2io.c
> > > index 1d3c4474b7cb..a83d61d45936 100644
> > > --- a/drivers/net/ethernet/neterion/s2io.c
> > > +++ b/drivers/net/ethernet/neterion/s2io.c
> > > @@ -2386,7 +2386,7 @@ static void free_tx_buffers(struct s2io_nic *nic)
> > >   			skb = s2io_txdl_getskb(&mac_control->fifos[i], txdp, j);
> > >   			if (skb) {
> > >   				swstats->mem_freed += skb->truesize;
> > > -				dev_kfree_skb(skb);
> > > +				dev_consume_skb_irq(skb);
> > >   				cnt++;
> > >   			}
> > >   		}
> > > -- 
> > > 2.25.1
> > > 
> > .
diff mbox series

Patch

diff --git a/drivers/net/ethernet/neterion/s2io.c b/drivers/net/ethernet/neterion/s2io.c
index 1d3c4474b7cb..a83d61d45936 100644
--- a/drivers/net/ethernet/neterion/s2io.c
+++ b/drivers/net/ethernet/neterion/s2io.c
@@ -2386,7 +2386,7 @@  static void free_tx_buffers(struct s2io_nic *nic)
 			skb = s2io_txdl_getskb(&mac_control->fifos[i], txdp, j);
 			if (skb) {
 				swstats->mem_freed += skb->truesize;
-				dev_kfree_skb(skb);
+				dev_consume_skb_irq(skb);
 				cnt++;
 			}
 		}