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From:   Rob Herring <robh@kernel.org>
Date:   Fri, 19 Feb 2021 08:16:46 -0600
Message-ID: <CAL_JsqJiRV5xShOgso0PH2pFhv-yozay58i1uGQC0dJCVxkJPA@mail.gmail.com>
Subject: Re: [PATCH] of: error: 'const struct kimage' has no member named 'arch'
To:     Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Cc:     Thiago Jung Bauermann <bauerman@linux.ibm.com>,
        Mimi Zohar <zohar@linux.ibm.com>,
        "AKASHI, Takahiro" <takahiro.akashi@linaro.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Will Deacon <will@kernel.org>, Joe Perches <joe@perches.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Stephen Rothwell <sfr@canb.auug.org.au>,
        James Morse <james.morse@arm.com>,
        Sasha Levin <sashal@kernel.org>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        linux-integrity@vger.kernel.org,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
        devicetree@vger.kernel.org,
        linuxppc-dev <linuxppc-dev@lists.ozlabs.org>
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On Thu, Feb 18, 2021 at 8:53 PM Lakshmi Ramasubramanian
<nramas@linux.microsoft.com> wrote:
>
> On 2/18/21 5:13 PM, Thiago Jung Bauermann wrote:
> >
> > Lakshmi Ramasubramanian <nramas@linux.microsoft.com> 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@linux.microsoft.com>
> >>>> Fixes: 33488dc4d61f ("of: Add a common kexec FDT setup function")
> >>>> Reported-by: kernel test robot <lkp@intel.com>
> >>>> ---
> >>>>    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