On Thu, Feb 18, 2021 at 8:53 PM Lakshmi Ramasubramanian
<nramas@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On 2/18/21 5:13 PM, Thiago Jung Bauermann wrote:
> >
> > Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx> writes:
> >
> >> On 2/18/21 4:07 PM, Mimi Zohar wrote:
> >>
> >> Hi Mimi,
> >>
> >>> On Thu, 2021-02-18 at 14:33 -0800, Lakshmi Ramasubramanian wrote:
> >>>> of_kexec_alloc_and_setup_fdt() defined in drivers/of/kexec.c builds
> >>>> a new device tree object that includes architecture specific data
> >>>> for kexec system call. This should be defined only if the architecture
> >>>> being built defines kexec architecture structure "struct kimage_arch".
> >>>>
> >>>> Define a new boolean config OF_KEXEC that is enabled if
> >>>> CONFIG_KEXEC_FILE and CONFIG_OF_FLATTREE are enabled, and
> >>>> the architecture is arm64 or powerpc64. Build drivers/of/kexec.c
> >>>> if CONFIG_OF_KEXEC is enabled.
> >>>>
> >>>> Signed-off-by: Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx>
> >>>> Fixes: 33488dc4d61f ("of: Add a common kexec FDT setup function")
> >>>> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> >>>> ---
> >>>> drivers/of/Kconfig | 6 ++++++
> >>>> drivers/of/Makefile | 7 +------
> >>>> 2 files changed, 7 insertions(+), 6 deletions(-)
> >>>>
> >>>> diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
> >>>> index 18450437d5d5..f2e8fa54862a 100644
> >>>> --- a/drivers/of/Kconfig
> >>>> +++ b/drivers/of/Kconfig
> >>>> @@ -100,4 +100,10 @@ config OF_DMA_DEFAULT_COHERENT
> >>>> # arches should select this if DMA is coherent by default for OF devices
> >>>> bool
> >>>> +config OF_KEXEC
> >>>> + bool
> >>>> + depends on KEXEC_FILE
> >>>> + depends on OF_FLATTREE
> >>>> + default y if ARM64 || PPC64
> >>>> +
> >>>> endif # OF
> >>>> diff --git a/drivers/of/Makefile b/drivers/of/Makefile
> >>>> index c13b982084a3..287579dd1695 100644
> >>>> --- a/drivers/of/Makefile
> >>>> +++ b/drivers/of/Makefile
> >>>> @@ -13,11 +13,6 @@ obj-$(CONFIG_OF_RESERVED_MEM) += of_reserved_mem.o
> >>>> obj-$(CONFIG_OF_RESOLVE) += resolver.o
> >>>> obj-$(CONFIG_OF_OVERLAY) += overlay.o
> >>>> obj-$(CONFIG_OF_NUMA) += of_numa.o
> >>>> -
> >>>> -ifdef CONFIG_KEXEC_FILE
> >>>> -ifdef CONFIG_OF_FLATTREE
> >>>> -obj-y += kexec.o
> >>>> -endif
> >>>> -endif
> >>>> +obj-$(CONFIG_OF_KEXEC) += kexec.o
> >>>> obj-$(CONFIG_OF_UNITTEST) += unittest-data/
> >>> Is it possible to reuse CONFIG_HAVE_IMA_KEXEC here?
> >>>
> >>
> >> For ppc64 CONFIG_HAVE_IMA_KEXEC is selected when CONFIG_KEXEC_FILE is enabled.
> >> So I don't see a problem in reusing CONFIG_HAVE_IMA_KEXEC for ppc.
> >>
> >> But for arm64, CONFIG_HAVE_IMA_KEXEC is enabled in the final patch in the patch
> >> set (the one for carrying forward IMA log across kexec for arm64). arm64 calls
> >> of_kexec_alloc_and_setup_fdt() prior to enabling CONFIG_HAVE_IMA_KEXEC and hence
> >> breaks the build for arm64.
> >
> > One problem is that I believe that this patch won't placate the robot,
> > because IIUC it generates config files at random and this change still
> > allows hppa and s390 to enable CONFIG_OF_KEXEC.
>
> I enabled CONFIG_OF_KEXEC for s390. With my patch applied,
> CONFIG_OF_KEXEC is removed. So I think the robot enabling this config
> would not be a problem.
>
> >
> > Perhaps a new CONFIG_HAVE_KIMAGE_ARCH option? Not having that option
> > would still allow building kexec.o, but would be used inside kexec.c to
> > avoid accessing kimage.arch members.
> >
>
> I think this is a good idea - a new CONFIG_HAVE_KIMAGE_ARCH, which will
> be selected by arm64 and ppc for now. I tried this, and it fixes the
> build issue.
>
> Although, the name for the new config can be misleading since PARISC,
> for instance, also defines "struct kimage_arch". Perhaps,
> CONFIG_HAVE_ELF_KIMAGE_ARCH since of_kexec_alloc_and_setup_fdt() is
> accessing ELF specific fields in "struct kimage_arch"?
>
> Rob/Mimi - please let us know which approach you think is better.
I'd just move the fields to kimage.
Rob
