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

[Jiri Olsa <olsajiri@gmail.com>]

On Fri, Nov 15, 2024 at 06:17:12PM +0100, Laura Nao wrote:
> On 11/13/24 10:37, Laura Nao wrote:
> > 
> > Currently, KernelCI only retains the bzImage, not the vmlinux binary. The
> > bzImage can be downloaded from the same link mentioned above by selecting
> > 'kernel' from the dropdown menu (modules can also be downloaded the same
> > way). I’ll try to replicate the build on my end and share the vmlinux
> > with DWARF data stripped for convenience.
> > 
> 
> 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?

yes, that seems wrong.. but I can't reproduce with your config
together with pahole 1.24 .. could you try with latest one?

jirka

> 
> I'll dig a bit deeper and report back if I can find anything else.
> 
> [1] https://people.collabora.com/~laura.nao/dbg-btf-mismatch-next-20241113/vmlinux
> [2] https://people.collabora.com/~laura.nao/dbg-btf-mismatch-next-20241113/vmlinux.raw
> [3] https://people.collabora.com/~laura.nao/dbg-btf-mismatch-next-20241113/cros_kbd_led_backlight.ko
> [4] https://people.collabora.com/~laura.nao/dbg-btf-mismatch-next-20241113/cros_kbd_led_backlight.ko.raw
> [5] https://pastebin.com/raw/FvvrPhAY
> 
> Best,
> 
> Laura
>