Re: [dpdk-dev] [PATCH] kni: fix compilation on SLES15-SP3

[Christian Ehrhardt <christian.ehrhardt@canonical.com>]

On Thu, Jun 17, 2021 at 10:25 AM Marco Varlese <marco.varlese@suse.com> wrote:
>
> Hello,
>
> On 6/17/21 8:41 AM, Thomas Monjalon wrote:
> > 17/06/2021 08:14, Christian Ehrhardt:
> >> On Thu, Jun 10, 2021 at 12:30 PM Christian Ehrhardt
> >> <christian.ehrhardt@canonical.com> wrote:
> >>> On Thu, Jun 10, 2021 at 10:39 AM Christian Ehrhardt
> >>> <christian.ehrhardt@canonical.com> wrote:
> >>>> On Tue, Jun 8, 2021 at 1:17 PM Ferruh Yigit <ferruh.yigit@intel.com> wrote:
> >>>>> On 6/2/2021 3:33 PM, Christian Ehrhardt wrote:
> >>>>>> Like what was done for mainline kernel in commit 38ad54f3bc76 ("kni: fix
> >>>>>> build with Linux 5.6"), a new parameter 'txqueue' has to be added to
> >>>>>> 'ndo_tx_timeout' ndo on SLES 15-SP3 kernel.
> >>>>>>
> >>>>>> Caused by:
> >>>>>>    commit c3bf155c40e9db722feb8a08c19efd44c12d5294
> >>>>>>    Author: Thomas Bogendoerfer <tbogendoerfer@suse.de>
> >>>>>>    Date:   Fri Sep 11 16:08:31 2020 +0200
> >>>>>>        - netdev: pass the stuck queue to the timeout handler
> >>>>>>          (jsc#SLE-13536).
> >>>>>>        - Refresh patches.suse/sfc-move-various-functions.patch.
> >>>>>>
> >>>>>> That is part of the SLES 5.3.18 kernel and therefore the
> >>>>>> version we check for.
> >>>>>>
> >>>>>> Cc: stable@dpdk.org
> >>>>>>
> >>>>>> Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
> >>>>> Hi Christian,
> >>>>>
> >>>>> There is a build error reported in CI [1] with 'SUSE15-64'.
> >>>>> Can't the check 'linux version >= 5.3.18" may hit multiple SUSE versions, with
> >>>>> some has the patch mentioned above backported and some did not?
> >>>>> Can 'SLE_VERSION_CODE' be used to differentiate the SUSE versions?
> >>>> I don't have a perfect insight in the SUSE distro variants and their
> >>>> kernel versions.
> >>>>> 5.3.18 in SLES15-SP3 was what broke it and I have hoped that this would apply in general.
> >>>> But the error above seems we have others that are > 5.3.18 but at the
> >>>> same time not have the backport.
> >>>>
> >>>> I'll try to create a v3, but do we have anyone from Suse to usually
> >>>> directly ping for feedback on this?
> >>> With the new version (not submitted since it fails me) you can have a
> >>> look at my personal WIP branch:
> >>> => https://github.com/cpaelzer/dpdk-stable-queue/commit/43b908fe83e9cd68b08e259c0ace26ec692bb737
> >> Hello everyone,
> >> Ferruh and I reached out to the Suse people working on DPDK in the
> >> past as well as those doing the kernel backport that breaks it now.
> >> (I'll add them to CC here as well)
> >> Unfortunately there was no feedback in a week, but OTOH I also don't
> >> want to stall releases for too long due to this.
> >>
> >> I'll try to summarize the current understanding of this case again
> >>
> >> [1] breaks our KNI build.
> >>
> >> SLE_VERSION isn't provided by their Kernel; it is in DPDKs
> >> kernel/linux/kni/compat.h and not further maintained for a while.
> >> So we can't differentiate SLE15SP2 vs SLE15SP3 via that.
> >>
> >> The offending change was introduced in their kernel by [1]
> >> $ git tag --contains c3bf155c40e9 | sort | head
> >> rpm-5.3.18-24
> >> ...
> >>
> >> But checking just the kernel version 5.3.18 (as my initial patch had)
> >> won't work either.
> >> The problem is that this only checks the three levels of kernel
> >> version, but not the packaging level.
> >> And to make things even more fun, while I don't know if opensuse leap
> >> has the patch applied or not atm, but the kernel version there might
> >> make this even more complex as it is 5.3.18-lp152 at the moment.
> >>
> >> We have now:
> >> SLE15 SP2 5.3.18-22
> >> SLE15 SP3 5.3.18-57 (>=24)
> >> opensuse_leap 5.3.18-lp152
> >>
> >> Without a change SLE15SP3 is broken due to that backport.
> >> By checking on >=5.3.18 we could fix SP3, but break SP2 and maybe opensuse_leap.
> >>
> >> Maybe there is something on LOCALVERSION/EXTRAVERSION we can use, but
> >> "guessing" how the Suse kernel behaves isn't a good approach.
>
> You could try using these:
>
> -- CONFIG_SUSE_VERSION
>
> -- CONFIG_SUSE_PATCHLEVEL
>
> for your build-time dependencies.
>
> It's as fragile as the approach of using KERNEL_VERSION but it might
> help with the current issue.

Hi Marco,
my inbox has hidden this answer for a while :-/

What would the expected content of these be for the three kernels in my example?

SLE15 SP2 5.3.18-22
SLE15 SP3 5.3.18-57
opensuse_leap 5.3.18-lp152

I don't have all (any TBH) of those environments, so knowing what
values to expect will help to write the checks.

>
> >> Once Suse lets us know how to better differentiate their packaging
> >> version we can reconsider a proper fix for this.
> >>
> >> But without further input from Suse I'd (for now) ask to keep things
> >> as is (= not applying my patch).
> >> Due to that it will build in the same places it has built in the past.
> >> If we find a solution it can be in the next release in ~3 months, but
> >> I'll not further stall e.g. 19.11.9 that I'm working on right now.
> >>
> >> [1]: https://github.com/SUSE/kernel/commit/c3bf155c40e9
> > Thank you for the summary.
> >
> > This explains well why we should stop supporting KNI.
> >
> >
>


-- 
Christian Ehrhardt
Staff Engineer, Ubuntu Server
Canonical Ltd