Re: [PATCH RFC Dovetail 6.16 1/5] kernel/entry: irq_pipeline: Do not leave .noinstr.text section

[Philippe Gerum <rpm@xenomai.org>]

Florian Bezdeka <florian.bezdeka@siemens.com> writes:

> On Fri, 2025-09-26 at 10:49 +0200, Philippe Gerum wrote:
>> Florian Bezdeka <florian.bezdeka@siemens.com> writes:
>> 
>> > Fixing the following warning by moving the call to irqentry_syncstage()
>> > into a instrumentation_begin() section.
>> > 
>> > vmlinux.o: warning: objtool: irqentry_exit+0xab: call to synchronize_pipeline() leaves .noinstr.text section
>> > 
>> > Signed-off-by: Florian Bezdeka <florian.bezdeka@siemens.com>
>> > ---
>> >  kernel/entry/common.c | 4 ++--
>> >  1 file changed, 2 insertions(+), 2 deletions(-)
>> > 
>> > diff --git a/kernel/entry/common.c b/kernel/entry/common.c
>> > index 583dcef13c7c0..284d41cb1c918 100644
>> > --- a/kernel/entry/common.c
>> > +++ b/kernel/entry/common.c
>> > @@ -393,6 +393,7 @@ noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t state)
>> >  		return;
>> >  	}
>> >  
>> > +	instrumentation_begin();
>> >  	synchronized = irqentry_syncstage(state);
>> > 
>> 
>> This means that we won't have ftracing or anything that depends on
>> instrumentation in any inband irq handler triggered during stage sync
>> from this code path.
>
> Hm. Really? The instrumentation is now enabled before running into
> irqendtry_syncstage(). No?
>
> Seems I have some issues to fully understand that instrumentation
> thingy. Let me double check...

Nope, I got this backwards, your code is right. /me multiplexing way too
much ATM.

-- 
Philippe.