Re: [REGRESSION] module BTF validation failure (Error -22) on next

From: Jiri Olsa
Date: Thu Dec 05 2024 - 05:33:13 EST


On Wed, Dec 04, 2024 at 04:53:05PM +0100, Laura Nao wrote:
> On 11/15/24 18:17, Laura Nao wrote:
> > I managed to reproduce the issue locally and I've uploaded the vmlinux[1]
> > (stripped of DWARF data) and vmlinux.raw[2] files, as well as one of the
> > modules[3] and its btf data[4] extracted with:
> >
> > bpftool -B vmlinux btf dump file cros_kbd_led_backlight.ko > cros_kbd_led_backlight.ko.raw
> >
> > Looking again at the logs[5], I've noticed the following is reported:
> >
> > [ 0.415885] BPF: type_id=115803 offset=177920 size=1152
> > [ 0.416029] BPF:
> > [ 0.416083] BPF: Invalid offset
> > [ 0.416165] BPF:
> >
> > There are two different definitions of rcu_data in '.data..percpu', one
> > is a struct and the other is an integer:
> >
> > type_id=115801 offset=177920 size=1152 (VAR 'rcu_data')
> > type_id=115803 offset=177920 size=1152 (VAR 'rcu_data')
> >
> > [115801] VAR 'rcu_data' type_id=115572, linkage=static
> > [115803] VAR 'rcu_data' type_id=1, linkage=static
> >
> > [115572] STRUCT 'rcu_data' size=1152 vlen=69
> > [1] INT 'long unsigned int' size=8 bits_offset=0 nr_bits=64 encoding=(none)
> >
> > I assume that's not expected, correct?
> >
> > I'll dig a bit deeper and report back if I can find anything else.
>
> I ran a bisection, and it appears the culprit commit is:
> https://lore.kernel.org/all/20241021080856.48746-2-ubizjak@xxxxxxxxx/

which tree are you using, I can't see this in linu-next ?

thanks,
jirka

>
> Hi Uros, do you have any suggestions or insights on resolving this issue?
>
> This problem is now impacting mainline as well. The full context can be
> found at the beginning of this thread[1].
>
> Thanks,
>
> Laura
>
> [1] https://lore.kernel.org/all/20241106160820.259829-1-laura.nao@xxxxxxxxxxxxx/
>
> #regzbot introduced: 001217defd
>
>