Re: [PATCH 4.14 000/159] 4.14.9-stable review

[Andre Tomt]

On 24. des. 2017 20:37, Ivan Kozik wrote:
> On Fri, Dec 22, 2017 at 8:44 AM, Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > This is the start of the stable review cycle for the 4.14.9 release.
> > There are 159 patches in this series, all will be posted as a response
> > to this one.  If anyone has any issues with these being applied, please
> > let me know.
> >
> > Responses should be made by Sun Dec 24 08:45:36 UTC 2017.
> > Anything received after that time might be too late.
>
> > Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> >      x86/unwind: Make CONFIG_UNWINDER_ORC=y the default in kconfig for 64-bit
>
> This is uncovering a very difficult-to-debug build failure with NVIDIA DKMS:
> with CONFIG_UNWINDER_ORC=y, out-of-tree modules hit this rule in
> scripts/Makefile.build:
>
> $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
>
> and fail (here, at least) to build tools/objtool/objtool (note: I do have
> libelf-dev installed)
>
> After editing dkms.conf to do `make --debug=a -j1`, I see make output:
>
>   Considering target file
> '/var/lib/dkms/nvidia-current/387.34/build/nvidia/nv-gpu-numa.o'.
>    File '/var/lib/dkms/nvidia-current/387.34/build/nvidia/nv-gpu-numa.o'
> does not exist.
>    Looking for an implicit rule for
> '/var/lib/dkms/nvidia-current/387.34/build/nvidia/nv-gpu-numa.o'.
>    [...]
>    Trying rule prerequisite 'tools/objtool/objtool'.
>    Looking for a rule with intermediate file 'tools/objtool/objtool'.
>     Avoiding implicit rule recursion.
>
> then silently fail to build objtool, silently fail to build all the .o files,
> then continue until ld finally errors out trying to link nonexistent object
> files.
>
> If things look alright to you, and objtool is known to work with out-of-tree
> modules, and the Debian packaging just needs to be adjusted, please ignore;
> I figured I'd send this anyway because it was such a pain to debug.

The linux-header packages dkms builds against need to include objtool 
when the ORC unwinder is enabled.

Changing the default like that is a pretty big change for a stable release.