Re: ima measurement carrying on -mm

[ebiederm@xmission.com (Eric W. Biederman)]

Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> writes:

> Am Donnerstag, 29 September 2016, 14:02:06 schrieb Andrew Morton:
>> On Thu, 29 Sep 2016 17:44:10 -0300 Thiago Jung Bauermann 
> <bauerman@linux.vnet.ibm.com> wrote:
>> > Hello Andrew,
>> > 
>> > You have in the -mm tree a version of the "kexec handover buffer" and
>> > "ima carry measurement list" patches that were NAKed by Eric Biederman.
>> > I would just like to double-check that there's no risk of that version
>> > reaching v4.9.
>> > 
>> > Mimi posted v5 of a merged patch set that addresses Eric's concern:
>> > 
>> > https://lists.ozlabs.org/pipermail/linuxppc-dev/2016-September/149183.ht
>> > ml
>> > 
>> > There are no separate kexec handover patches anymore. They were folded
>> > into the series above. The kexec code is simplified now, it doesn't
>> > support updating the buffer and recalculating the hash on reboot, and
>> > is now IMA- specific instead of a generic kexec feature.
>> 
>> Yup, thanks.
>> 
>> I wasn't thinking any of this material is suitable for 4.9.  Seems that
>> a bit more consideration will be needed.  Am I wrong about that?
>
> Yes regarding the "ima carry measurement list" patches, but I was hoping 
> that at least the kexec_file_load patches would be upstreamed.

Oh bah. I was confused about that straight forward adding of kexec_file
support to powerpc.  I thought that was already in existence.

In that case let me say I am concerned about modifying the flattened
device tree, especially in the kexec_file.  I would think that the
flattened device tree would be something that it would be desirable to
keep intact.

I know in the x86 boot protocol we have some variables that are purely
passed by the bootloader (like the command line) and some that just
representations of firmware provided information.  Does powerpc not have
that separation.

I would think being able to pass the flattened device tree through
unchanged would be very desirable in the kexec case as it removes the
possibility of error.

>> Are all of these -mm patches up to date?
>> 
>> kexec_file-allow-arch-specific-memory-walking-for-kexec_add_buffer.patch
>> kexec_file-change-kexec_add_buffer-to-take-kexec_buf-as-argument.patch
>> kexec_file-factor-out-kexec_locate_mem_hole-from-kexec_add_buffer.patch
>> powerpc-change-places-using-config_kexec-to-use-config_kexec_core-instead.
>> patch
>> powerpc-factor-out-relocation-code-from-module_64c-to-elf_util_64c.patch
>> powerpc-generalize-elf64_apply_relocate_add.patch
>> powerpc-adapt-elf64_apply_relocate_add-for-kexec_file_load.patch
>> powerpc-add-functions-to-read-elf-files-of-any-endianness.patch
>> powerpc-implement-kexec_file_load.patch
>> powerpc-add-code-to-work-with-device-trees-in-kexec_file_load.patch
>> powerpc-add-support-for-loading-elf-kernels-with-kexec_file_load.patch
>> powerpc-add-support-for-loading-elf-kernels-with-kexec_file_load-fix.patch
>> powerpc-add-purgatory-for-kexec_file_load-implementation.patch
>> powerpc-add-purgatory-for-kexec_file_load-implementation-fix.patch
>> powerpc-enable-config_kexec_file-in-powerpc-server-defconfigs.patch
>
> Yes, the above are the latest version (v8).

Eric