Re: [PATCH v4] kni: fix build with Linux 5.18

[Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>]

On 6/6/22 08:59, Jiri Slaby wrote:
> On 05. 06. 22, 10:22, Andrew Rybchenko wrote:
>> On 6/1/22 09:53, Jiri Slaby wrote:
>>> Since commit 2655926aea9b (net: Remove netif_rx_any_context() and
>>> netif_rx_ni().) in 5.18, netif_rx_ni() no longer exists as netif_rx()
>>> can be called from any context. So define HAVE_NETIF_RX_NI for older
>>> releases and call the appropriate function in kni_net.
>>>
>>> There were other attempts to fix this:
>>> https://patches.dpdk.org/project/dpdk/patch/20220521070642.35413-1-humin29@huawei.com/ 
>>>
>>> https://patches.dpdk.org/project/dpdk/patch/20220511112334.3233433-1-mingli.yu@windriver.com/ 
>>>
>>>
>>> But neither of them ensures netif_rx_ni() is used on older kernel. This
>>> might lead to deadlocks or other problems there.
>>>
>>> Cc: stable@dpdk.org
>>> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
>>> ---
>>> [v4]
>>> - really switch the #if test
>>> [v3]
>>> - reference other patches
>>> - switch the #if test expressions to conform to the checker
>>> [v2]
>>> - forgot to amend the #else/#endif typo fix
>>>
>>>   kernel/linux/kni/compat.h  | 4 ++++
>>>   kernel/linux/kni/kni_net.c | 4 ++++
>>>   2 files changed, 8 insertions(+)
>>>
>>> diff --git a/kernel/linux/kni/compat.h b/kernel/linux/kni/compat.h
>>> index 664785674ff1..0db29a4a6f61 100644
>>> --- a/kernel/linux/kni/compat.h
>>> +++ b/kernel/linux/kni/compat.h
>>> @@ -141,3 +141,7 @@
>>>   #if KERNEL_VERSION(5, 9, 0) > LINUX_VERSION_CODE
>>>   #define HAVE_TSK_IN_GUP
>>>   #endif
>>> +
>>> +#if KERNEL_VERSION(5, 18, 0) > LINUX_VERSION_CODE
>>> +#define HAVE_NETIF_RX_NI
>>> +#endif
>>> diff --git a/kernel/linux/kni/kni_net.c b/kernel/linux/kni/kni_net.c
>>> index 29e5b9e21f9e..a8b092b7567d 100644
>>> --- a/kernel/linux/kni/kni_net.c
>>> +++ b/kernel/linux/kni/kni_net.c
>>> @@ -441,7 +441,11 @@ kni_net_rx_normal(struct kni_dev *kni)
>>>           skb->ip_summed = CHECKSUM_UNNECESSARY;
>>>           /* Call netif interface */
>>> +#ifdef HAVE_NETIF_RX_NI
>>>           netif_rx_ni(skb);
>>> +#else
>>> +        netif_rx(skb);
>>> +#else
>>>           /* Update statistics */
>>>           dev->stats.rx_bytes += len;
>>
>> Applied to dpdk-next-net/main with minor fixes in the description, 
>> thanks.
> 
> Sorry, it appears I sent the old version again. The latter #else should 
> have been #endif. Do you want me to send a followup patch?
> 
> thanks,

Oh, I'm sorry as well that I didn't catch it. Frankly speaking I'm
surprised that all CI does not catch it. test-meson-build.sh does
not catch it as well with default. I've tuned my build checks to care
about it.

Thomas, thanks a lot for the quick fix.