Re: [PATCH v5 1/2] xen: Allow lib-y targets to also be .init.o

[Alejandro Vallejo <alejandro.garciavallejo@amd.com>]

On Thu Jan 22, 2026 at 12:04 PM CET, Jan Beulich wrote:
> On 22.01.2026 12:02, Alejandro Vallejo wrote:
>> On Thu Jan 22, 2026 at 11:01 AM CET, Jan Beulich wrote:
>>> On 22.01.2026 10:49, Jan Beulich wrote:
>>>> On 21.01.2026 16:47, Alejandro Vallejo wrote:
>>>>> There's some assumptions as to which targets may be init-only. But
>>>>> there's little reason to preclude libraries from being init-only.
>>>>>
>>>>> Signed-off-by: Alejandro Vallejo <alejandro.garciavallejo@amd.com>
>>>>> Reviewed-by: Jan Beulich <jbeulich@suse.com>
>>>>
>>>> I can't tell (yet) what it is, but as per CI something's clearly wrong with this
>>>> change. Both xilinx-smoke-dom0less-arm64-* and qemu-smoke-dom0*-debug* fail with
>>>> it in place. qemu-smoke-dom0-arm64-gcc (no "debug") was fine, suggesting it may
>>>> be an early assertion triggering.
>>>
>>> Or an early UBSAN failure. I think ...
>>>
>>>>> --- a/xen/Rules.mk
>>>>> +++ b/xen/Rules.mk
>>>>> @@ -130,9 +130,9 @@ endif
>>>>>  
>>>>>  targets += $(targets-for-builtin)
>>>>>  
>>>>> -$(filter %.init.o,$(obj-y) $(obj-bin-y) $(extra-y)): CFLAGS-y += -DINIT_SECTIONS_ONLY
>>>>> +$(filter %.init.o,$(obj-y) $(obj-bin-y) $(extra-y) $(lib-y)): CFLAGS-y += -DINIT_SECTIONS_ONLY
>>>>>  
>>>>> -non-init-objects = $(filter-out %.init.o, $(obj-y) $(obj-bin-y) $(extra-y))
>>>>> +non-init-objects = $(filter-out %.init.o, $(obj-y) $(obj-bin-y) $(extra-y) $(lib-y))
>>>
>>> ... this is the problem: You're _adding_ library files here which weren't there
>>> before. Why $(lib-y) isn't here I don't really known, but as per the CI results
>>> there must be a reason for this.
>> 
>> Apologies for the unintended breakage. I should've checked the baseline for
>> arm before ruling out this patch being the cause (it did fire in my pipeline,
>> but didn't consider how this could affect arm and attributed it to a spurious
>> failure).
>> 
>> So we're neither doing UBSAN nor collecting coverage data from libs? Great. One
>> more task to the pile, I guess. Seeing how...
>> 
>>  $(non-init-objects): _c_flags += $(cov-cflags-y)
>>  [snip]
>>  $(non-init-objects): _c_flags += $(UBSAN_FLAGS)
>> 
>> I'll try to clean this mess. :/
>
> In the meantime, should I give your patch another try with that one change dropped?
>
> Jan

Sure, thanks.

Cheers,
Alejandro