Re: [PATCH net-next 4/5] tun: Add support for SCTP checksum offload

[Michael S. Tsirkin]

On Mon, Apr 02, 2018 at 09:40:05AM -0400, Vladislav Yasevich wrote:
> Adds a new tun offload flag to allow for SCTP checksum offload.
> The flag has to be set by the user and defaults to "no offload".
> 
> Signed-off-by: Vladislav Yasevich 

When would user set this flag? Wouldn't that be when
userspace is ready to get SCTP packets without a checksum?
Seems to be this is an indication that when userspace
is qemu running a guest, said guest needs to communicate
the new ability to qemu.

> ---
>  drivers/net/tun.c | 5 +
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/net/tun.c b/drivers/net/tun.c
> index a1ba262..263bcbe 100644
> --- a/drivers/net/tun.c
> +++ b/drivers/net/tun.c
> @@ -2719,6 +2719,11 @@ static int set_offload(struct tun_struct *tun, 
> unsigned long arg)
>   arg &= ~TUN_F_UFO;
>   }
>  
> + if (arg & TUN_F_SCTP_CSUM) {
> + features |= NETIF_F_SCTP_CRC;
> + arg &= ~TUN_F_SCTP_CSUM;
> + }
> +
>   /* This gives the user a way to test for new features in future by
>* trying to set them. */
>   if (arg)
> -- 
> 2.9.5

Re: [PATCH net-next 4/5] tun: Add support for SCTP checksum offload

[kbuild test robot]

Hi Vladislav,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on net-next/master]

url:
https://github.com/0day-ci/linux/commits/Vladislav-Yasevich/virtio-net-Add-SCTP-checksum-offload-support/20180402-221407
config: m68k-hp300_defconfig (attached as .config)
compiler: m68k-linux-gnu-gcc (Debian 7.2.0-11) 7.2.0
reproduce:
wget 
https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O 
~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=m68k 

Note: the 
linux-review/Vladislav-Yasevich/virtio-net-Add-SCTP-checksum-offload-support/20180402-221407
 HEAD 5e0497a085e70055a1981959802173f4ff05c86b builds fine.
  It only hurts bisectibility.

All errors (new ones prefixed by >>):

   drivers/net/tun.c: In function 'set_offload':
>> drivers/net/tun.c:2722:12: error: 'TUN_F_SCTP_CSUM' undeclared (first use in 
>> this function); did you mean 'TUN_F_CSUM'?
 if (arg & TUN_F_SCTP_CSUM) {
   ^~~
   TUN_F_CSUM
   drivers/net/tun.c:2722:12: note: each undeclared identifier is reported only 
once for each function it appears in

vim +2722 drivers/net/tun.c

  2696  
  2697  /* This is like a cut-down ethtool ops, except done via tun fd so no
  2698   * privs required. */
  2699  static int set_offload(struct tun_struct *tun, unsigned long arg)
  2700  {
  2701  netdev_features_t features = 0;
  2702  
  2703  if (arg & TUN_F_CSUM) {
  2704  features |= NETIF_F_HW_CSUM;
  2705  arg &= ~TUN_F_CSUM;
  2706  
  2707  if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
  2708  if (arg & TUN_F_TSO_ECN) {
  2709  features |= NETIF_F_TSO_ECN;
  2710  arg &= ~TUN_F_TSO_ECN;
  2711  }
  2712  if (arg & TUN_F_TSO4)
  2713  features |= NETIF_F_TSO;
  2714  if (arg & TUN_F_TSO6)
  2715  features |= NETIF_F_TSO6;
  2716  arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
  2717  }
  2718  
  2719  arg &= ~TUN_F_UFO;
  2720  }
  2721  
> 2722  if (arg & TUN_F_SCTP_CSUM) {
  2723  features |= NETIF_F_SCTP_CRC;
  2724  arg &= ~TUN_F_SCTP_CSUM;
  2725  }
  2726  
  2727  /* This gives the user a way to test for new features in future 
by
  2728   * trying to set them. */
  2729  if (arg)
  2730  return -EINVAL;
  2731  
  2732  tun->set_features = features;
  2733  tun->dev->wanted_features &= ~TUN_USER_FEATURES;
  2734  tun->dev->wanted_features |= features;
  2735  netdev_update_features(tun->dev);
  2736  
  2737  return 0;
  2738  }
  2739  

---
0-DAY kernel test infrastructureOpen Source Technology Center
https://lists.01.org/pipermail/kbuild-all   Intel Corporation


.config.gz
Description: application/gzip

[PATCH net-next 4/5] tun: Add support for SCTP checksum offload

[Vladislav Yasevich]

Adds a new tun offload flag to allow for SCTP checksum offload.
The flag has to be set by the user and defaults to "no offload".

Signed-off-by: Vladislav Yasevich 
---
 drivers/net/tun.c | 5 +
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index a1ba262..263bcbe 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -2719,6 +2719,11 @@ static int set_offload(struct tun_struct *tun, unsigned 
long arg)
arg &= ~TUN_F_UFO;
}
 
+   if (arg & TUN_F_SCTP_CSUM) {
+   features |= NETIF_F_SCTP_CRC;
+   arg &= ~TUN_F_SCTP_CSUM;
+   }
+
/* This gives the user a way to test for new features in future by
 * trying to set them. */
if (arg)
-- 
2.9.5