linux/tools
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
..
accounting
arch tools headers UAPI: Sync x86's asm/kvm.h with the kernel sources 2021-11-18 10:08:07 -03:00
bootconfig bootconfig: Cleanup dummy headers in tools/bootconfig 2021-10-10 22:16:02 -04:00
bpf Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2021-12-10 15:56:13 -08:00
build Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2021-12-10 15:56:13 -08:00
cgroup
counter tools/counter: Create Counter tools 2021-10-17 10:54:16 +01:00
debugging
edid
firewire
firmware
gpio
hv
iio
include bpf: Add bpf_strncmp helper 2021-12-11 17:40:23 -08:00
io_uring
kvm/kvm_stat KVM: kvm_stat: do not show halt_wait_ns 2021-10-18 14:07:18 -04:00
laptop
leds
lib libbpf: Don't validate TYPE_ID relo's original imm value 2021-12-12 17:26:24 -08:00
memory-model
objtool objtool: Fix pv_ops noinstr validation 2021-12-03 09:11:42 +01:00
pci
pcmcia
perf Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2021-12-10 15:56:13 -08:00
power
rcu tools/rcu: Add an extract-stall script 2021-09-16 10:31:26 -07:00
scripts tools, build: Add RISC-V to HOSTARCH parsing 2021-11-01 17:08:21 +01:00
spi
testing selftests/bpf: Remove last bpf_create_map_xattr from test_verifier 2021-12-12 16:46:15 -08:00
thermal/tmon
time
tracing tools/latency-collector: Use correct size when writing queue_full_warning 2021-10-25 22:27:19 -04:00
usb usb: testusb: Fix for showing the connection speed 2021-09-14 10:31:41 +02:00
virtio
vm tools/vm/page-types.c: print file offset in hexadecimal 2021-11-06 13:30:40 -07:00
wmi
Makefile tools/lib/lockdep: drop liblockdep 2021-11-12 11:07:17 -08:00