diff options
author | Stanislav Fomichev <[email protected]> | 2019-11-27 08:14:10 -0800 |
---|---|---|
committer | Alexei Starovoitov <[email protected]> | 2019-11-27 11:11:42 -0800 |
commit | da5fb18225b49b97bb37c51bcbbb2990a507c364 (patch) | |
tree | 2d8c17dcb803aee714dd523ceacea53824021fdb | |
parent | d0f010434124598988ba1c97fbb0e4e820ff5d8c (diff) |
bpf: Support pre-2.25-binutils objcopy for vmlinux BTF
If vmlinux BTF generation fails, but CONFIG_DEBUG_INFO_BTF is set,
.BTF section of vmlinux is empty and kernel will prohibit
BPF loading and return "in-kernel BTF is malformed".
--dump-section argument to binutils' objcopy was added in version 2.25.
When using pre-2.25 binutils, BTF generation silently fails. Convert
to --only-section which is present on pre-2.25 binutils.
Documentation/process/changes.rst states that binutils 2.21+
is supported, not sure those standards apply to BPF subsystem.
v2:
* exit and print an error if gen_btf fails (John Fastabend)
v3:
* resend with Andrii's Acked-by/Tested-by tags
Fixes: 341dfcf8d78ea ("btf: expose BTF info through sysfs")
Signed-off-by: Stanislav Fomichev <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Tested-by: Andrii Nakryiko <[email protected]>
Acked-by: Andrii Nakryiko <[email protected]>
Cc: John Fastabend <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]
-rwxr-xr-x | scripts/link-vmlinux.sh | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 06495379fcd8..2998ddb323e3 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -127,7 +127,8 @@ gen_btf() cut -d, -f1 | cut -d' ' -f2) bin_format=$(LANG=C ${OBJDUMP} -f ${1} | grep 'file format' | \ awk '{print $4}') - ${OBJCOPY} --dump-section .BTF=.btf.vmlinux.bin ${1} 2>/dev/null + ${OBJCOPY} --set-section-flags .BTF=alloc -O binary \ + --only-section=.BTF ${1} .btf.vmlinux.bin 2>/dev/null ${OBJCOPY} -I binary -O ${bin_format} -B ${bin_arch} \ --rename-section .data=.BTF .btf.vmlinux.bin ${2} } @@ -253,6 +254,10 @@ btf_vmlinux_bin_o="" if [ -n "${CONFIG_DEBUG_INFO_BTF}" ]; then if gen_btf .tmp_vmlinux.btf .btf.vmlinux.bin.o ; then btf_vmlinux_bin_o=.btf.vmlinux.bin.o + else + echo >&2 "Failed to generate BTF for vmlinux" + echo >&2 "Try to disable CONFIG_DEBUG_INFO_BTF" + exit 1 fi fi |