Backport an upstream patch series that adds backend elfutils support for
DWARF relocations in MIPS debug info. This support is needed by pahole to
generate BTF for modules in BTF-enabled kernel builds.
The problem first manifests as pahole warnings during build:
BTF [M] lib/libcrc32c.ko
die__process_unit: DW_TAG_compile_unit (0x11) @ <0x932d> not handled!
die__process_unit: tag not supported 0x11 (compile_unit)!
die__process: got compile_unit unexpected tag after DW_TAG_compile_unit!
die__process_unit: DW_TAG_compile_unit (0x11) @ <0x99a3> not handled!
die__process_unit: tag not supported 0x11 (compile_unit)!
die__process: got compile_unit unexpected tag after DW_TAG_compile_unit!
During system boot the problem then causes module loading failures, which
may result in many other runtime issues:
[ 13.169785] kmodloader: loading kernel modules from /etc/modules.d/*
[ ... ]
[ 17.422840] mac80211_hwsim: initializing netlink
[ 17.526518] PPP generic driver version 2.4.2
[ 17.550346] NET: Registered PF_PPPOX protocol family
[ 17.795353] kmodloader: 26 modules could not be probed
[ 17.796084] kmodloader: dependency not loaded nf_conntrack
[ 17.796737] kmodloader: - act_connmark - 1
[ 17.797402] kmodloader: dependency not loaded nf_conntrack
[ 17.798056] kmodloader: - act_ctinfo - 1
[ ... ]
Link: https://lore.kernel.org/bpf/ZlkoM6%2FPSxVcGM6X@kodidev-ubuntu/
Signed-off-by: Tony Ambardar <itugrok@yahoo.com>
Link: https://github.com/openwrt/openwrt/pull/15697
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>