On Thu, 4 Feb 2021 at 16:53, Guillaume Tucker <guillaume.tuc...@collabora.com> wrote: > > On 04/02/2021 15:42, Ard Biesheuvel wrote: > > On Thu, 4 Feb 2021 at 12:32, Guillaume Tucker > > <guillaume.tuc...@collabora.com> wrote: > >> > >> On 04/02/2021 10:33, Guillaume Tucker wrote: > >>> On 04/02/2021 10:27, Ard Biesheuvel wrote: > >>>> On Thu, 4 Feb 2021 at 11:06, Russell King - ARM Linux admin > >>>> <li...@armlinux.org.uk> wrote: > >>>>> > >>>>> On Thu, Feb 04, 2021 at 10:07:58AM +0100, Ard Biesheuvel wrote: > >>>>>> On Thu, 4 Feb 2021 at 09:43, Guillaume Tucker > >>>>>> <guillaume.tuc...@collabora.com> wrote: > >>>>>>> > >>>>>>> Hi Ard, > >>>>>>> > >>>>>>> Please see the bisection report below about a boot failure on > >>>>>>> rk3288 with next-20210203. It was also bisected on > >>>>>>> imx6q-var-dt6customboard with next-20210202. > >>>>>>> > >>>>>>> Reports aren't automatically sent to the public while we're > >>>>>>> trialing new bisection features on kernelci.org but this one > >>>>>>> looks valid. > >>>>>>> > >>>>>>> The kernel is most likely crashing very early on, so there's > >>>>>>> nothing in the logs. Please let us know if you need some help > >>>>>>> with debugging or trying a fix on these platforms. > >>>>>>> > >>>>>> > >>>>>> Thanks for the report. > >>>>> > >>>>> Ard, > >>>>> > >>>>> I want to send my fixes branch today which includes your regression > >>>>> fix that caused this regression. > >>>>> > >>>>> As this is proving difficult to fix, I can only drop your fix from > >>>>> my fixes branch - and given that this seems to be problematical, I'm > >>>>> tempted to revert the original change at this point which should fix > >>>>> both of these regressions - and then we have another go at getting rid > >>>>> of the set/way instructions during the next cycle. > >>>>> > >>>>> Thoughts? > >>>>> > >>>> > >>>> Hi Russell, > >>>> > >>>> If Guillaume is willing to do the experiment, and it fixes the issue, > >>> > >>> Yes, I'm running some tests with that fix now and should have > >>> some results shortly. > >> > >> Yes it does fix the issue: > >> > >> https://lava.collabora.co.uk/scheduler/job/3173819 > >> > >> with Ard's fix applied to this test branch: > >> > >> > >> https://gitlab.collabora.com/gtucker/linux/-/commits/next-20210203-ard-fix/ > >> > >> > >> +clang +Nick > >> > >> It's worth mentioning that the issue only happens with kernels > >> built with Clang. As you can see there are several other arm > >> platforms failing with clang-11 builds but booting fine with > >> gcc-8: > >> > >> > >> https://kernelci.org/test/job/next/branch/master/kernel/next-20210203/plan/baseline/ > >> > >> Here's a sample build log: > >> > >> > >> https://storage.staging.kernelci.org/gtucker/next-20210203-ard-fix/v5.10-rc4-24722-g58b6c0e507b7-gtucker_single-staging-33/arm/multi_v7_defconfig/clang-11/build.log > >> > >> Essentially: > >> > >> make -j18 ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- LLVM=1 CC="ccache > >> clang" zImage > >> > >> I believe it should be using the GNU assembler as LLVM_IAS=1 is > >> not defined, but there may be something more subtle about it. > >> > > > > > > Do you have a link for a failing zImage built from multi_v7_defconfig? > > Sure, this one was built from a plain next-20210203: > > > http://storage.staging.kernelci.org/gtucker/next-20210203-ard-fix/v5.10-rc4-24722-g58b6c0e507b7-gtucker_single-staging-33/arm/multi_v7_defconfig/clang-11/zImage > > You can also find the dtbs, modules and other things in that same > directory. > > For the record, here's the test job that used it: > > https://lava.collabora.co.uk/scheduler/job/3173792 >
Thanks. That zImage boots fine locally. Unfortunately, I don't have rk3288 hardware to reproduce. Could you please point me to the list of all the other platforms that failed to boot this image? To be honest, I am slightly annoyed that a change that works fine with GCC but does not work with Clang version 11.1.0-++20210130110826+3a8282376b6c-1~exp1~20210130221445.158 (where exp means experimental, I suppose) is the reason for this discussion, especially because the change is in asm code. Is it possible to build with Clang but use the GNU linker?
