Re: [PATCH] xfrm: kconfig: Fix XFRM_OFFLOAD dependency on XFRM

From: Leon Romanovsky
Date: Tue Jul 25 2023 - 01:19:30 EST


On Tue, Jul 25, 2023 at 07:41:49AM +0300, Ilia Lin wrote:
> Hi Leon,

You was already asked do not top-post.
https://lore.kernel.org/netdev/20230718105446.GD8808@unreal/
Please stop it.

>
> This is exactly like I described:
> * xfrm.h is included from the net/core/sock.c unconditionally.
> * If CONFIG_XFRM_OFFLOAD is set, then the xfrm_dst_offload_ok() is
> being compiled.
> * If CONFIG_XFRM is not set, the struct dst_entry doesn't have the xfrm member.
> * xfrm_dst_offload_ok() tries to access the dst->xfrm and that fails to compile.

I asked two questions. First one was "How did you set XFRM_OFFLOAD
without XFRM?".

Thanks


>
>
> Thanks,
> Ilia Lin
>
> On Mon, Jul 24, 2023 at 9:11 PM Leon Romanovsky <leon@xxxxxxxxxx> wrote:
> >
> > On Mon, Jul 24, 2023 at 12:00:44PM +0300, Ilia Lin wrote:
> > > If XFRM_OFFLOAD is configured, but XFRM is not
> >
> > How did you do it?
> >
> > >, it will cause
> > > compilation error on include xfrm.h:
> > > C 05:56:39 In file included from /src/linux/kernel_platform/msm-kernel/net/core/sock.c:127:
> > > C 05:56:39 /src/linux/kernel_platform/msm-kernel/include/net/xfrm.h:1932:30: error: no member named 'xfrm' in 'struct dst_entry'
> > > C 05:56:39 struct xfrm_state *x = dst->xfrm;
> > > C 05:56:39 ~~~ ^
> > >
> > > Making the XFRM_OFFLOAD select the XFRM.
> > >
> > > Fixes: 48e01e001da31 ("ixgbe/ixgbevf: fix XFRM_ALGO dependency")
> > > Reported-by: Ilia Lin <ilia.lin@xxxxxxxxxx>
> > > Signed-off-by: Ilia Lin <ilia.lin@xxxxxxxxxx>
> > > ---
> > > net/xfrm/Kconfig | 1 +
> > > 1 file changed, 1 insertion(+)
> > >
> > > diff --git a/net/xfrm/Kconfig b/net/xfrm/Kconfig
> > > index 3adf31a83a79a..3fc2c1bcb5bbe 100644
> > > --- a/net/xfrm/Kconfig
> > > +++ b/net/xfrm/Kconfig
> > > @@ -10,6 +10,7 @@ config XFRM
> > >
> > > config XFRM_OFFLOAD
> > > bool
> > > + select XFRM
> >
> > struct dst_entry depends on CONFIG_XFRM and not on CONFIG_XFRM_OFFLOAD,
> > so it is unclear to me why do you need to add new "select XFRM" line.
> >
> > 26 struct dst_entry {
> > 27 struct net_device *dev;
> > 28 struct dst_ops *ops;
> > 29 unsigned long _metrics;
> > 30 unsigned long expires;
> > 31 #ifdef CONFIG_XFRM
> > 32 struct xfrm_state *xfrm;
> > 33 #else
> > 34 void *__pad1;
> > 35 #endif
> > 36 int
> >
> > Thanks