linux/tools/lib
Andrii Nakryiko 4b443bc178 libbpf: Don't validate TYPE_ID relo's original imm value
During linking, type IDs in the resulting linked BPF object file can
change, and so ldimm64 instructions corresponding to
BPF_CORE_TYPE_ID_TARGET and BPF_CORE_TYPE_ID_LOCAL CO-RE relos can get
their imm value out of sync with actual CO-RE relocation information
that's updated by BPF linker properly during linking process.

We could teach BPF linker to adjust such instructions, but it feels
a bit too much for linker to re-implement good chunk of
bpf_core_patch_insns logic just for this. This is a redundant safety
check for TYPE_ID relocations, as the real validation is in matching
CO-RE specs, so if that works fine, it's very unlikely that there is
something wrong with the instruction itself.

So, instead, teach libbpf (and kernel) to ignore insn->imm for
BPF_CORE_TYPE_ID_TARGET and BPF_CORE_TYPE_ID_LOCAL relos.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211213010706.100231-1-andrii@kernel.org
2021-12-12 17:26:24 -08:00
..
api tools api fs: Cache cgroupfs mount point 2021-02-17 15:09:08 -03:00
bpf libbpf: Don't validate TYPE_ID relo's original imm value 2021-12-12 17:26:24 -08:00
perf Merge remote-tracking branch 'torvalds/master' into perf/core 2021-10-26 11:03:02 -03:00
subcmd libsubcmd: add OPT_UINTEGER_OPTARG option type 2021-08-31 15:44:05 -03:00
symbol
traceevent KVM: x86/mmu: Rename "nxe" role bit to "efer_nx" for macro shenanigans 2021-06-24 18:00:41 -04:00
argv_split.c
bitmap.c tools lib: Adopt bitmap_intersects() operation from the kernel sources 2021-06-30 15:28:00 -03:00
ctype.c
find_bit.c tools: sync lib/find_bit implementation 2021-05-06 19:24:12 -07:00
hweight.c
list_sort.c tools lib: Adopt list_sort() from the kernel sources 2021-10-20 10:30:59 -03:00
rbtree.c tools/: replace HTTP links with HTTPS ones 2020-08-07 11:33:21 -07:00
str_error_r.c
string.c tools lib: Adopt memchr_inv() from kernel 2020-11-27 08:34:52 -03:00
vsprintf.c
zalloc.c