On Fri, Mar 01, 2019 at 11:13:10AM -0300, Joao Moreira wrote:
> From: Josh Poimboeuf <[email protected]>
>
> Create cmd_klp_convert and hook it into scripts/Makefile.modpost.
> cmd_klp_convert invokes klp-convert with the right arguments for the
> conversion of unresolved symbols inside a livepatch.
>
> [khlebnikov:
> * save cmd_ld_ko_o into .module.cmd, if_changed_rule doesn't do that
> * fix bashisms for debian where /bin/sh is a symlink to /bin/dash
> * rename rule_link_module to rule_ld_ko_o, otherwise arg-check inside
> if_changed_rule compares cmd_link_module and cmd_ld_ko_o
> * check modinfo -F livepatch only if CONFIG_LIVEPATCH is true
> ]
>
> [mbenes:
> * remove modinfo call. LIVEPATCH_ in Makefiled
> ]
>
> [jmoreira:
> * split up: move the .livepatch file-based scheme for identifying
> livepatches to a previous patch, as it was required for correctly
> building Symbols.list there.
> ]
>
> Signed-off-by: Josh Poimboeuf <[email protected]>
> Signed-off-by: Konstantin Khlebnikov <[email protected]>
> Signed-off-by: Miroslav Benes <[email protected]>
> Signed-off-by: Joao Moreira <[email protected]>
> ---
> scripts/Kbuild.include | 4 +++-
> scripts/Makefile.modpost | 16 +++++++++++++++-
> scripts/mod/modpost.c | 6 +++++-
> scripts/mod/modpost.h | 1 +
> 4 files changed, 24 insertions(+), 3 deletions(-)
>
>
> [ ... snip ... ]
>
> diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
> index 7d4af0d0accb..da779a185218 100644
> --- a/scripts/Makefile.modpost
> +++ b/scripts/Makefile.modpost
> @@ -125,8 +125,22 @@ quiet_cmd_ld_ko_o = LD [M] $@
> -o $@ $(filter-out FORCE,$^) ; \
> $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
>
> +SLIST = $(objtree)/Symbols.list
> +KLP_CONVERT = scripts/livepatch/klp-convert
> +quiet_cmd_klp_convert = KLP $@
> + cmd_klp_convert = mv $@ $(@:.ko=.klp.o); \
> + $(KLP_CONVERT) $(SLIST) $(@:.ko=.klp.o) $@
> +
> +define rule_ld_ko_o
> + $(call cmd,ld_ko_o) $(cmd_ld_ko_o) ; \
^
Should there be a ';' semicolon here (and maybe a line-break) between
$(call cmd,ld_ko_o) and $(cmd_ld_ko_o)?
I didn't see this in my x86_64 VM, but on a ppc64le box, I kept getting
really strange build errors that I traced to this line. Without a
semicolon, the build was trying to run a make command with a linker
command smashed onto the end of it:
make -f ./arch/powerpc/Makefile.postlink crypto/xts.ko ld -r -EL -m elf64lppc -T ./scripts/module-common.lds -T ./arch/powerpc/kernel/module.lds --save-restore-funcs --build-id -o crypto/xts.ko crypto/xts.o crypto/xts.mod.o
Now, klp-convert looks like will need some ppc64le work as well, as it's
confused about .TOC. symbols:
CC samples/livepatch/livepatch-annotated-sample.mod.o
CC samples/livepatch/livepatch-callbacks-busymod.mod.o
CC samples/livepatch/livepatch-callbacks-demo.mod.o
CC samples/livepatch/livepatch-callbacks-mod.mod.o
CC samples/livepatch/livepatch-sample.mod.o
CC samples/livepatch/livepatch-shadow-fix1.mod.o
CC samples/livepatch/livepatch-shadow-fix2.mod.o
CC samples/livepatch/livepatch-shadow-mod.mod.o
LD [M] samples/livepatch/livepatch-annotated-sample.ko
LD [M] samples/livepatch/livepatch-callbacks-demo.ko
KLP samples/livepatch/livepatch-annotated-sample.ko
LD [M] samples/livepatch/livepatch-callbacks-mod.ko
KLP samples/livepatch/livepatch-callbacks-demo.ko
LD [M] samples/livepatch/livepatch-sample.ko
LD [M] samples/livepatch/livepatch-shadow-fix1.ko
klp-convert: Define KLP_SYMPOS for the symbol: .TOC.
Valid KLP_SYMPOS for symbol .TOC.:
[ ... snip listing of all .TOC's across the kernel ... ]
but we can save that for another day.
-- Joe
On 2019-03-22 11:54, Joe Lawrence wrote:
> On Fri, Mar 01, 2019 at 11:13:10AM -0300, Joao Moreira wrote:
>> From: Josh Poimboeuf <[email protected]>
>>
>> Create cmd_klp_convert and hook it into scripts/Makefile.modpost.
>> cmd_klp_convert invokes klp-convert with the right arguments for the
>> conversion of unresolved symbols inside a livepatch.
>>
>> [khlebnikov:
>> * save cmd_ld_ko_o into .module.cmd, if_changed_rule doesn't do that
>> * fix bashisms for debian where /bin/sh is a symlink to /bin/dash
>> * rename rule_link_module to rule_ld_ko_o, otherwise arg-check inside
>> if_changed_rule compares cmd_link_module and cmd_ld_ko_o
>> * check modinfo -F livepatch only if CONFIG_LIVEPATCH is true
>> ]
>>
>> [mbenes:
>> * remove modinfo call. LIVEPATCH_ in Makefiled
>> ]
>>
>> [jmoreira:
>> * split up: move the .livepatch file-based scheme for identifying
>> livepatches to a previous patch, as it was required for correctly
>> building Symbols.list there.
>> ]
>>
>> Signed-off-by: Josh Poimboeuf <[email protected]>
>> Signed-off-by: Konstantin Khlebnikov <[email protected]>
>> Signed-off-by: Miroslav Benes <[email protected]>
>> Signed-off-by: Joao Moreira <[email protected]>
>> ---
>> scripts/Kbuild.include | 4 +++-
>> scripts/Makefile.modpost | 16 +++++++++++++++-
>> scripts/mod/modpost.c | 6 +++++-
>> scripts/mod/modpost.h | 1 +
>> 4 files changed, 24 insertions(+), 3 deletions(-)
>>
>>
>> [ ... snip ... ]
>>
>> diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
>> index 7d4af0d0accb..da779a185218 100644
>> --- a/scripts/Makefile.modpost
>> +++ b/scripts/Makefile.modpost
>> @@ -125,8 +125,22 @@ quiet_cmd_ld_ko_o = LD [M] $@
>> -o $@ $(filter-out FORCE,$^) ;
>> \
>> $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
>>
>> +SLIST = $(objtree)/Symbols.list
>> +KLP_CONVERT = scripts/livepatch/klp-convert
>> +quiet_cmd_klp_convert = KLP $@
>> + cmd_klp_convert = mv $@ $(@:.ko=.klp.o); \
>> + $(KLP_CONVERT) $(SLIST) $(@:.ko=.klp.o) $@
>> +
>> +define rule_ld_ko_o
>> + $(call cmd,ld_ko_o) $(cmd_ld_ko_o) ; \
> ^
> Should there be a ';' semicolon here (and maybe a line-break) between
> $(call cmd,ld_ko_o) and $(cmd_ld_ko_o)?
>
> I didn't see this in my x86_64 VM, but on a ppc64le box, I kept getting
> really strange build errors that I traced to this line. Without a
> semicolon, the build was trying to run a make command with a linker
> command smashed onto the end of it:
>
> make -f ./arch/powerpc/Makefile.postlink crypto/xts.ko ld -r -EL -m
> elf64lppc -T ./scripts/module-common.lds -T
> ./arch/powerpc/kernel/module.lds --save-restore-funcs --build-id -o
> crypto/xts.ko crypto/xts.o crypto/xts.mod.o
>
>
> Now, klp-convert looks like will need some ppc64le work as well, as
> it's
> confused about .TOC. symbols:
>
> CC samples/livepatch/livepatch-annotated-sample.mod.o
> CC samples/livepatch/livepatch-callbacks-busymod.mod.o
> CC samples/livepatch/livepatch-callbacks-demo.mod.o
> CC samples/livepatch/livepatch-callbacks-mod.mod.o
> CC samples/livepatch/livepatch-sample.mod.o
> CC samples/livepatch/livepatch-shadow-fix1.mod.o
> CC samples/livepatch/livepatch-shadow-fix2.mod.o
> CC samples/livepatch/livepatch-shadow-mod.mod.o
> LD [M] samples/livepatch/livepatch-annotated-sample.ko
> LD [M] samples/livepatch/livepatch-callbacks-demo.ko
> KLP samples/livepatch/livepatch-annotated-sample.ko
> LD [M] samples/livepatch/livepatch-callbacks-mod.ko
> KLP samples/livepatch/livepatch-callbacks-demo.ko
> LD [M] samples/livepatch/livepatch-sample.ko
> LD [M] samples/livepatch/livepatch-shadow-fix1.ko
> klp-convert: Define KLP_SYMPOS for the symbol: .TOC.
> Valid KLP_SYMPOS for symbol .TOC.:
>
> [ ... snip listing of all .TOC's across the kernel ... ]
>
> but we can save that for another day.
>
Hi Joe, first of all, thank you for you in-depth review. I did not have
the time to go through everything yet, and I'll reply properly to the
other comments soon. Yet, I would like to add a quick note here, since
you are testing ppc64le. ppc64le is exactly one of the things I have
been dealing with in the last two days, specifically the .TOC. symbols
(there is also another bug related to converting relocations of symbols
with index 0, but this one is architecture agnostic).
If you would like to take a look, the fix is in the latest commit here:
- https://github.com/SUSE/klp-convert/tree/fixppc64le
I would be very glad if you have any comment or input on that, and I
guess that if the fix is that simple, I can manage to squash it into v3.
Thanks,
João
>
> -- Joe
On 3/22/19 12:37 PM, Joao Moreira wrote:
> On 2019-03-22 11:54, Joe Lawrence wrote:
>> On Fri, Mar 01, 2019 at 11:13:10AM -0300, Joao Moreira wrote:
>>> From: Josh Poimboeuf <[email protected]>
>>>
>>> Create cmd_klp_convert and hook it into scripts/Makefile.modpost.
>>> cmd_klp_convert invokes klp-convert with the right arguments for the
>>> conversion of unresolved symbols inside a livepatch.
>>>
>>> [khlebnikov:
>>> * save cmd_ld_ko_o into .module.cmd, if_changed_rule doesn't do that
>>> * fix bashisms for debian where /bin/sh is a symlink to /bin/dash
>>> * rename rule_link_module to rule_ld_ko_o, otherwise arg-check inside
>>> if_changed_rule compares cmd_link_module and cmd_ld_ko_o
>>> * check modinfo -F livepatch only if CONFIG_LIVEPATCH is true
>>> ]
>>>
>>> [mbenes:
>>> * remove modinfo call. LIVEPATCH_ in Makefiled
>>> ]
>>>
>>> [jmoreira:
>>> * split up: move the .livepatch file-based scheme for identifying
>>> livepatches to a previous patch, as it was required for correctly
>>> building Symbols.list there.
>>> ]
>>>
>>> Signed-off-by: Josh Poimboeuf <[email protected]>
>>> Signed-off-by: Konstantin Khlebnikov <[email protected]>
>>> Signed-off-by: Miroslav Benes <[email protected]>
>>> Signed-off-by: Joao Moreira <[email protected]>
>>> ---
>>> scripts/Kbuild.include | 4 +++-
>>> scripts/Makefile.modpost | 16 +++++++++++++++-
>>> scripts/mod/modpost.c | 6 +++++-
>>> scripts/mod/modpost.h | 1 +
>>> 4 files changed, 24 insertions(+), 3 deletions(-)
>>>
>>>
>>> [ ... snip ... ]
>>>
>>> diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
>>> index 7d4af0d0accb..da779a185218 100644
>>> --- a/scripts/Makefile.modpost
>>> +++ b/scripts/Makefile.modpost
>>> @@ -125,8 +125,22 @@ quiet_cmd_ld_ko_o = LD [M] $@
>>> -o $@ $(filter-out FORCE,$^) ;
>>> \
>>> $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
>>>
>>> +SLIST = $(objtree)/Symbols.list
>>> +KLP_CONVERT = scripts/livepatch/klp-convert
>>> +quiet_cmd_klp_convert = KLP $@
>>> + cmd_klp_convert = mv $@ $(@:.ko=.klp.o); \
>>> + $(KLP_CONVERT) $(SLIST) $(@:.ko=.klp.o) $@
>>> +
>>> +define rule_ld_ko_o
>>> + $(call cmd,ld_ko_o) $(cmd_ld_ko_o) ; \
>> ^
>> Should there be a ';' semicolon here (and maybe a line-break) between
>> $(call cmd,ld_ko_o) and $(cmd_ld_ko_o)?
>>
>> I didn't see this in my x86_64 VM, but on a ppc64le box, I kept getting
>> really strange build errors that I traced to this line. Without a
>> semicolon, the build was trying to run a make command with a linker
>> command smashed onto the end of it:
>>
>> make -f ./arch/powerpc/Makefile.postlink crypto/xts.ko ld -r -EL -m
>> elf64lppc -T ./scripts/module-common.lds -T
>> ./arch/powerpc/kernel/module.lds --save-restore-funcs --build-id -o
>> crypto/xts.ko crypto/xts.o crypto/xts.mod.o
>>
>>
>> Now, klp-convert looks like will need some ppc64le work as well, as
>> it's
>> confused about .TOC. symbols:
>>
>> CC samples/livepatch/livepatch-annotated-sample.mod.o
>> CC samples/livepatch/livepatch-callbacks-busymod.mod.o
>> CC samples/livepatch/livepatch-callbacks-demo.mod.o
>> CC samples/livepatch/livepatch-callbacks-mod.mod.o
>> CC samples/livepatch/livepatch-sample.mod.o
>> CC samples/livepatch/livepatch-shadow-fix1.mod.o
>> CC samples/livepatch/livepatch-shadow-fix2.mod.o
>> CC samples/livepatch/livepatch-shadow-mod.mod.o
>> LD [M] samples/livepatch/livepatch-annotated-sample.ko
>> LD [M] samples/livepatch/livepatch-callbacks-demo.ko
>> KLP samples/livepatch/livepatch-annotated-sample.ko
>> LD [M] samples/livepatch/livepatch-callbacks-mod.ko
>> KLP samples/livepatch/livepatch-callbacks-demo.ko
>> LD [M] samples/livepatch/livepatch-sample.ko
>> LD [M] samples/livepatch/livepatch-shadow-fix1.ko
>> klp-convert: Define KLP_SYMPOS for the symbol: .TOC.
>> Valid KLP_SYMPOS for symbol .TOC.:
>>
>> [ ... snip listing of all .TOC's across the kernel ... ]
>>
>> but we can save that for another day.
>>
>
> Hi Joe, first of all, thank you for you in-depth review. I did not have
> the time to go through everything yet, and I'll reply properly to the
> other comments soon. Yet, I would like to add a quick note here, since
> you are testing ppc64le. ppc64le is exactly one of the things I have
> been dealing with in the last two days, specifically the .TOC. symbols
> (there is also another bug related to converting relocations of symbols
> with index 0, but this one is architecture agnostic).
>
> If you would like to take a look, the fix is in the latest commit here:
> - https://github.com/SUSE/klp-convert/tree/fixppc64le
>
> I would be very glad if you have any comment or input on that, and I
> guess that if the fix is that simple, I can manage to squash it into v3.
Hi João,
I added https://github.com/SUSE/klp-convert/commit/69b89ef5c366 on top
of my
https://github.com/joe-lawrence/linux/tree/klp-convert-v2-rebase-review
branch with positive results:
(No build klp-convert build complaints)
% uname -r
Linux ibm-p9z-21-lp26.mpc.lab.eng.bos.redhat.com 5.1.0-rc1+ #6 SMP
Thu Mar 21 11:40:24 EDT 2019 ppc64le ppc64le ppc64le GNU/Linux
% insmod samples/livepatch/livepatch-annotated-sample.ko
% grep -o 'livepatch.*' /proc/cmdline
livepatch=1
% ./tools/testing/selftests/livepatch/test-livepatch.sh
TEST: basic function patching ... ok
TEST: multiple livepatches ... ok
TEST: atomic replace livepatch ... ok
TEST: klp-convert symbols ... ok
There may be more ppc64le specifics lurking, but if we could get samples
and self-tests working, I think we'd be in good shape for v3.
-- Joe
On Fri, 22 Mar 2019, Joe Lawrence wrote:
> On Fri, Mar 01, 2019 at 11:13:10AM -0300, Joao Moreira wrote:
> > From: Josh Poimboeuf <[email protected]>
> >
> > Create cmd_klp_convert and hook it into scripts/Makefile.modpost.
> > cmd_klp_convert invokes klp-convert with the right arguments for the
> > conversion of unresolved symbols inside a livepatch.
> >
> > [khlebnikov:
> > * save cmd_ld_ko_o into .module.cmd, if_changed_rule doesn't do that
> > * fix bashisms for debian where /bin/sh is a symlink to /bin/dash
> > * rename rule_link_module to rule_ld_ko_o, otherwise arg-check inside
> > if_changed_rule compares cmd_link_module and cmd_ld_ko_o
> > * check modinfo -F livepatch only if CONFIG_LIVEPATCH is true
> > ]
> >
> > [mbenes:
> > * remove modinfo call. LIVEPATCH_ in Makefiled
> > ]
> >
> > [jmoreira:
> > * split up: move the .livepatch file-based scheme for identifying
> > livepatches to a previous patch, as it was required for correctly
> > building Symbols.list there.
> > ]
> >
> > Signed-off-by: Josh Poimboeuf <[email protected]>
> > Signed-off-by: Konstantin Khlebnikov <[email protected]>
> > Signed-off-by: Miroslav Benes <[email protected]>
> > Signed-off-by: Joao Moreira <[email protected]>
> > ---
> > scripts/Kbuild.include | 4 +++-
> > scripts/Makefile.modpost | 16 +++++++++++++++-
> > scripts/mod/modpost.c | 6 +++++-
> > scripts/mod/modpost.h | 1 +
> > 4 files changed, 24 insertions(+), 3 deletions(-)
> >
> >
> > [ ... snip ... ]
> >
> > diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
> > index 7d4af0d0accb..da779a185218 100644
> > --- a/scripts/Makefile.modpost
> > +++ b/scripts/Makefile.modpost
> > @@ -125,8 +125,22 @@ quiet_cmd_ld_ko_o = LD [M] $@
> > -o $@ $(filter-out FORCE,$^) ; \
> > $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
> >
> > +SLIST = $(objtree)/Symbols.list
> > +KLP_CONVERT = scripts/livepatch/klp-convert
> > +quiet_cmd_klp_convert = KLP $@
> > + cmd_klp_convert = mv $@ $(@:.ko=.klp.o); \
> > + $(KLP_CONVERT) $(SLIST) $(@:.ko=.klp.o) $@
> > +
> > +define rule_ld_ko_o
> > + $(call cmd,ld_ko_o) $(cmd_ld_ko_o) ; \
> ^
> Should there be a ';' semicolon here (and maybe a line-break) between
> $(call cmd,ld_ko_o) and $(cmd_ld_ko_o)?
Probably yes.
Originally there was
$(call echo-cmd,ld_ko_o) $(cmd_ld_ko_o) ;
but "echo-" disappeared somewhere. Joao?
So maybe even
$(call cmd,ld_ko_o)
could be enough, because cmd contains echo-cmd, but I'm not good at
reading scripts/Kbuild.include.
> I didn't see this in my x86_64 VM, but on a ppc64le box, I kept getting
> really strange build errors that I traced to this line. Without a
> semicolon, the build was trying to run a make command with a linker
> command smashed onto the end of it:
>
> make -f ./arch/powerpc/Makefile.postlink crypto/xts.ko ld -r -EL -m elf64lppc -T ./scripts/module-common.lds -T ./arch/powerpc/kernel/module.lds --save-restore-funcs --build-id -o crypto/xts.ko crypto/xts.o crypto/xts.mod.o
Miroslav
On 4/4/19 8:31 AM, Miroslav Benes wrote:
> On Fri, 22 Mar 2019, Joe Lawrence wrote:
>
>> On Fri, Mar 01, 2019 at 11:13:10AM -0300, Joao Moreira wrote:
>>> From: Josh Poimboeuf <[email protected]>
>>>
>>> Create cmd_klp_convert and hook it into scripts/Makefile.modpost.
>>> cmd_klp_convert invokes klp-convert with the right arguments for the
>>> conversion of unresolved symbols inside a livepatch.
>>>
>>> [khlebnikov:
>>> * save cmd_ld_ko_o into .module.cmd, if_changed_rule doesn't do that
>>> * fix bashisms for debian where /bin/sh is a symlink to /bin/dash
>>> * rename rule_link_module to rule_ld_ko_o, otherwise arg-check inside
>>> if_changed_rule compares cmd_link_module and cmd_ld_ko_o
>>> * check modinfo -F livepatch only if CONFIG_LIVEPATCH is true
>>> ]
>>>
>>> [mbenes:
>>> * remove modinfo call. LIVEPATCH_ in Makefiled
>>> ]
>>>
>>> [jmoreira:
>>> * split up: move the .livepatch file-based scheme for identifying
>>> livepatches to a previous patch, as it was required for correctly
>>> building Symbols.list there.
>>> ]
>>>
>>> Signed-off-by: Josh Poimboeuf <[email protected]>
>>> Signed-off-by: Konstantin Khlebnikov <[email protected]>
>>> Signed-off-by: Miroslav Benes <[email protected]>
>>> Signed-off-by: Joao Moreira <[email protected]>
>>> ---
>>> scripts/Kbuild.include | 4 +++-
>>> scripts/Makefile.modpost | 16 +++++++++++++++-
>>> scripts/mod/modpost.c | 6 +++++-
>>> scripts/mod/modpost.h | 1 +
>>> 4 files changed, 24 insertions(+), 3 deletions(-)
>>>
>>>
>>> [ ... snip ... ]
>>>
>>> diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
>>> index 7d4af0d0accb..da779a185218 100644
>>> --- a/scripts/Makefile.modpost
>>> +++ b/scripts/Makefile.modpost
>>> @@ -125,8 +125,22 @@ quiet_cmd_ld_ko_o = LD [M] $@
>>> -o $@ $(filter-out FORCE,$^) ; \
>>> $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
>>>
>>> +SLIST = $(objtree)/Symbols.list
>>> +KLP_CONVERT = scripts/livepatch/klp-convert
>>> +quiet_cmd_klp_convert = KLP $@
>>> + cmd_klp_convert = mv $@ $(@:.ko=.klp.o); \
>>> + $(KLP_CONVERT) $(SLIST) $(@:.ko=.klp.o) $@
>>> +
>>> +define rule_ld_ko_o
>>> + $(call cmd,ld_ko_o) $(cmd_ld_ko_o) ; \
>> ^
>> Should there be a ';' semicolon here (and maybe a line-break) between
>> $(call cmd,ld_ko_o) and $(cmd_ld_ko_o)?
>
> Probably yes.
>
> Originally there was
> $(call echo-cmd,ld_ko_o) $(cmd_ld_ko_o) ;
>
> but "echo-" disappeared somewhere. Joao?
Hi,
I just verified my sources and the echo-cmd got lost in between the v2
rebases. I believe it must have happened while I was manually fixing a
conflict, or something. Sorry.
Here is a piece of the original snippet, as it was supposed to be:
define rule_ld_ko_o
$(call echo-cmd,ld_ko_o) $(cmd_ld_ko_o) ;
\
$(call save-cmd,ld_ko_o) ;
\
$(if $(CONFIG_LIVEPATCH), \
Joe, do you mind fixing it for v3?
Thanks for spotting it.
>
> So maybe even
> $(call cmd,ld_ko_o)
> could be enough, because cmd contains echo-cmd, but I'm not good at
> reading scripts/Kbuild.include.
>
>> I didn't see this in my x86_64 VM, but on a ppc64le box, I kept getting
>> really strange build errors that I traced to this line. Without a
>> semicolon, the build was trying to run a make command with a linker
>> command smashed onto the end of it:
>>
>> make -f ./arch/powerpc/Makefile.postlink crypto/xts.ko ld -r -EL -m elf64lppc -T ./scripts/module-common.lds -T ./arch/powerpc/kernel/module.lds --save-restore-funcs --build-id -o crypto/xts.ko crypto/xts.o crypto/xts.mod.o
>
> Miroslav
>