Re: pahole v1.24: FAILED: load BTF from vmlinux: Invalid argument

[Vitaly Chikunov <vt@altlinux.org>]

On Fri, Aug 26, 2022 at 05:52:20AM +0300, Vitaly Chikunov wrote:
> Arnaldo,
> 
> On Thu, Aug 25, 2022 at 08:16:20PM +0300, Vitaly Chikunov wrote:
> > On Thu, Aug 25, 2022 at 01:47:59PM -0300, Arnaldo Carvalho de Melo wrote:
> > > On Thu, Aug 25, 2022, 1:35 PM Vitaly Chikunov <vt@altlinux.org> wrote:
> > > >
> > > > I also noticed that after upgrading pahole to v1.24 kernel build (tested on
> > > > v5.18.19, v5.15.63, sorry for not testing on mainline) fails with:
> > > >
> > > >     BTFIDS  vmlinux
> > > >   + ./tools/bpf/resolve_btfids/resolve_btfids vmlinux
> > > >   FAILED: load BTF from vmlinux: Invalid argument
> > > >
> > > > Perhaps, .tmp_vmlinux.btf is generated incorrectly? Downgrading dwarves to
> > > > v1.23 resolves the issue.
> > > >
> > > 
> > > Can you try this, from Martin Reboredo (Archlinux):
> > > 
> > > Can you try a build of the kernel or the by passing the
> > > --skip_encoding_btf_enum64 to scripts/pahole-flags.sh?
> > > 
> > > Here's a patch for either in tree scripts/pahole-flags.sh or
> > > /usr/lib/modules/5.19.3-arch1-1/build/scripts/pahole-flags.sh
> > 
> > This patch helped and kernel builds successfully after applying it.
> > (Didn't notice this suggestion in release discussion thread.)
> 
> Even thought it now compiles with this patch, it does not boot
> afterwards (in virtme-like env), witch such console messages:

I'm talking here about 5.15.62. Yes, proposed patch does not apply there
(since there is no `scripts/pahole-flags.sh`), but I updated
`scripts/link-vmlinux.sh` with the similar `if` to append
`--skip_encoding_btf_enum64` which lets then compilation pass.

Thanks,

> 
>   [    0.767649] Run /init as init process
>   [    0.770858] BPF:[593] ENUM perf_event_task_context
>   [    0.771262] BPF:size=4 vlen=4
>   [    0.771511] BPF:
>   [    0.771680] BPF:Invalid btf_info kind_flag
>   [    0.772016] BPF:
>   [    0.772016]
>   [    0.772288] failed to validate module [9pnet] BTF: -22
>   init_module '9pnet.ko' error -1
>   [    0.785515] 9p: Unknown symbol p9_client_getattr_dotl (err -2)
>   [    0.786005] 9p: Unknown symbol p9_client_wstat (err -2)
>   [    0.786438] 9p: Unknown symbol p9_client_open (err -2)
>   [    0.786863] 9p: Unknown symbol p9_client_rename (err -2)
>   [    0.787307] 9p: Unknown symbol p9_client_remove (err -2)
>   [    0.787749] 9p: Unknown symbol p9_client_renameat (err -2)
>   [    0.788202] 9p: Unknown symbol p9_client_fcreate (err -2)
>   [    0.788651] 9p: Unknown symbol p9_is_proto_dotu (err -2)
>   [    0.789086] 9p: Unknown symbol p9_client_disconnect (err -2)
>   [    0.789558] 9p: Unknown symbol p9_client_attach (err -2)
>   [    0.790001] 9p: Unknown symbol p9stat_free (err -2)
>   [    0.790409] 9p: Unknown symbol p9_client_create (err -2)
>   [    0.790856] 9p: Unknown symbol p9_client_read_once (err -2)
>   [    0.791314] 9p: Unknown symbol p9_client_setattr (err -2)
>   [    0.791762] 9p: Unknown symbol p9_client_xattrwalk (err -2)
>   [    0.792222] 9p: Unknown symbol p9_client_destroy (err -2)
>   [    0.792674] 9p: Unknown symbol p9_client_unlinkat (err -2)
>   [    0.793124] 9p: Unknown symbol p9_client_mkdir_dotl (err -2)
>   [    0.793585] 9p: Unknown symbol p9_client_xattrcreate (err -2)
>   [    0.794055] 9p: Unknown symbol p9_client_create_dotl (err -2)
>   [    0.794527] 9p: Unknown symbol p9_client_lock_dotl (err -2)
>   [    0.794985] 9p: Unknown symbol p9_client_write (err -2)
>   [    0.795415] 9p: Unknown symbol p9_client_walk (err -2)
>   [    0.795837] 9p: Unknown symbol p9_show_client_options (err -2)
>   [    0.796308] 9p: Unknown symbol p9_client_read (err -2)
>   [    0.796731] 9p: Unknown symbol p9_client_fsync (err -2)
>   [    0.797158] 9p: Unknown symbol p9dirent_read (err -2)
>   [    0.797572] 9p: Unknown symbol p9_client_symlink (err -2)
>   [    0.798016] 9p: Unknown symbol p9_client_readlink (err -2)
>   [    0.798470] 9p: Unknown symbol p9_is_proto_dotl (err -2)
>   [    0.798908] 9p: Unknown symbol p9_client_clunk (err -2)
>   [    0.799339] 9p: Unknown symbol p9stat_read (err -2)
>   [    0.799747] 9p: Unknown symbol p9_client_statfs (err -2)
>   [    0.800184] 9p: Unknown symbol p9_client_link (err -2)
>   [    0.800612] 9p: Unknown symbol p9_client_stat (err -2)
>   [    0.801038] 9p: Unknown symbol p9_client_begin_disconnect (err -2)
>   [    0.801544] 9p: Unknown symbol p9_client_getlock_dotl (err -2)
>   [    0.802024] 9p: Unknown symbol p9_client_readdir (err -2)
>   [    0.802469] 9p: Unknown symbol p9_client_mknod_dotl (err -2)
>   init_module '9p.ko' error -1
>   [    0.809193] failed to validate module [virtio] BTF: -22
>   init_module 'virtio.ko' error -1
>   [    0.825316] failed to validate module [virtio_ring] BTF: -22
>   init_module 'virtio_ring.ko' error -1
>   [    0.841110] 9pnet_virtio: Unknown symbol register_virtio_driver (err -2)
>   [    0.841674] 9pnet_virtio: Unknown symbol p9_req_put (err -2)
>   [    0.842143] 9pnet_virtio: Unknown symbol unregister_virtio_driver (err -2)
>   [    0.842708] 9pnet_virtio: Unknown symbol p9_release_pages (err -2)
>   [    0.843209] 9pnet_virtio: Unknown symbol virtqueue_add_sgs (err -2)
>   [    0.843728] 9pnet_virtio: Unknown symbol virtqueue_get_buf (err -2)
>   [    0.844237] 9pnet_virtio: Unknown symbol virtqueue_kick (err -2)
>   [    0.844733] 9pnet_virtio: Unknown symbol v9fs_register_trans (err -2)
>   [    0.845256] 9pnet_virtio: Unknown symbol virtio_check_driver_offered_feature (err -2)
>   [    0.845893] 9pnet_virtio: Unknown symbol v9fs_unregister_trans (err -2)
>   [    0.846434] 9pnet_virtio: Unknown symbol p9_client_cb (err -2)
>   init_module '9pnet_virtio.ko' error -1
>   [    0.853175] failed to validate module [virtio_pci_modern_dev] BTF: -22
>   init_module 'virtio_pci_modern_dev.ko' error -1
>   [    0.869196] virtio_pci: Unknown symbol vring_transport_features (err -2)
>   [    0.869759] virtio_pci: Unknown symbol vp_modern_get_status (err -2)
>   [    0.870276] virtio_pci: Unknown symbol vp_modern_map_vq_notify (err -2)
>   [    0.870817] virtio_pci: Unknown symbol virtqueue_get_avail_addr (err -2)
>   [    0.871363] virtio_pci: Unknown symbol vp_modern_get_queue_size (err -2)
>   [    0.871912] virtio_pci: Unknown symbol vp_modern_remove (err -2)
>   [    0.872405] virtio_pci: Unknown symbol vring_create_virtqueue (err -2)
>   [    0.872938] virtio_pci: Unknown symbol vp_modern_get_features (err -2)
>   [    0.873470] virtio_pci: Unknown symbol vp_modern_set_status (err -2)
>   [    0.873986] virtio_pci: Unknown symbol vp_modern_queue_address (err -2)
>   [    0.874523] virtio_pci: Unknown symbol virtio_device_restore (err -2)
>   [    0.875050] virtio_pci: Unknown symbol vring_interrupt (err -2)
>   [    0.875544] virtio_pci: Unknown symbol virtio_config_changed (err -2)
>   [    0.876073] virtio_pci: Unknown symbol vp_modern_get_queue_enable (err -2)
>   [    0.876639] virtio_pci: Unknown symbol vp_modern_config_vector (err -2)
>   [    0.877172] virtio_pci: Unknown symbol virtqueue_get_vring_size (err -2)
>   [    0.877721] virtio_pci: Unknown symbol vp_modern_probe (err -2)
>   [    0.878205] virtio_pci: Unknown symbol unregister_virtio_device (err -2)
>   [    0.878753] virtio_pci: Unknown symbol virtqueue_get_desc_addr (err -2)
>   [    0.879288] virtio_pci: Unknown symbol vp_modern_set_queue_size (err -2)
>   [    0.879836] virtio_pci: Unknown symbol vp_modern_queue_vector (err -2)
>   [    0.880371] virtio_pci: Unknown symbol virtio_device_freeze (err -2)
>   [    0.880896] virtio_pci: Unknown symbol vp_modern_generation (err -2)
>   [    0.881417] virtio_pci: Unknown symbol virtio_break_device (err -2)
>   [    0.881969] virtio_pci: Unknown symbol vp_modern_set_features (err -2)
>   [    0.882501] virtio_pci: Unknown symbol virtqueue_get_used_addr (err -2)
>   [    0.883014] virtio_pci: Unknown symbol register_virtio_device (err -2)
>   [    0.883547] virtio_pci: Unknown symbol vp_modern_get_num_queues (err -2)
>   [    0.884090] virtio_pci: Unknown symbol vp_modern_set_queue_enable (err -2)
>   [    0.884684] virtio_pci: Unknown symbol vring_del_virtqueue (err -2)
>   init_module 'virtio_pci.ko' error -1
> 
> It seems the same is happened in Arch:
> 
>   https://bbs.archlinux.org/viewtopic.php?id=279132
> 
> And they reverted pahole to 1.23:
> 
>   https://github.com/archlinux/svntogit-packages/commits/packages/pahole/trunk/PKGBUILD
> 
> When I'm revering dwarves to 1.23 it resolves the issue for me too (in
> ALT).
> 
> Thanks,
> 
> 
> > 
> > Thanks!
> > 
> > > 
> > > diff --git a/scripts/pahole-flags.sh b/scripts/pahole-flags.sh
> > > index 0d99ef17e4a528..1f1f1d397c399a 100755
> > > --- a/scripts/pahole-flags.sh
> > > +++ b/scripts/pahole-flags.sh
> > > @@ -19,5 +19,9 @@ fi
> > >  if [ "${pahole_ver}" -ge "122" ]; then
> > >         extra_paholeopt="${extra_paholeopt} -j"
> > >  fi
> > > +if [ "${pahole_ver}" -ge "124" ]; then
> > > +       # see PAHOLE_HAS_LANG_EXCLUDE
> > > +       extra_paholeopt="${extra_paholeopt} --skip_encoding_btf_enum64"
> > > +fi
> > > 
> > >  echo ${extra_paholeopt}
> > > 
> > > >
> > > > Thanks,
> > > >
> > > >