diff mbox series

[v2,bpf-next,2/5] libbpf: support BTF_KIND_FLOAT during type compatibility checks in CO-RE

Message ID 20210426192949.416837-3-andrii@kernel.org (mailing list archive)
State Accepted
Delegated to: BPF
Headers show
Series CO-RE relocation selftests fixes | expand

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netdev/tree_selection success Clearly marked for bpf-next
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netdev/cc_maintainers fail 2 blamed authors not CCed: ast@kernel.org iii@linux.ibm.com; 7 maintainers not CCed: yhs@fb.com kpsingh@kernel.org kafai@fb.com iii@linux.ibm.com ast@kernel.org john.fastabend@gmail.com songliubraving@fb.com
netdev/source_inline success Was 0 now: 0
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netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/kdoc success Errors and warnings before: 0 this patch: 0
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netdev/checkpatch warning WARNING: line length of 81 exceeds 80 columns
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
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Commit Message

Andrii Nakryiko April 26, 2021, 7:29 p.m. UTC
Add BTF_KIND_FLOAT support when doing CO-RE field type compatibility check.
Without this, relocations against float/double fields will fail.

Also adjust one error message to emit instruction index instead of less
convenient instruction byte offset.

Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Fixes: 22541a9eeb0d ("libbpf: Add BTF_KIND_FLOAT support")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
---
 tools/lib/bpf/libbpf.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index a1cddd17af7d..e2a3cf437814 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -5115,6 +5115,7 @@  bpf_core_find_cands(struct bpf_object *obj, const struct btf *local_btf, __u32 l
  *     least one of enums should be anonymous;
  *   - for ENUMs, check sizes, names are ignored;
  *   - for INT, size and signedness are ignored;
+ *   - any two FLOATs are always compatible;
  *   - for ARRAY, dimensionality is ignored, element types are checked for
  *     compatibility recursively;
  *   - everything else shouldn't be ever a target of relocation.
@@ -5141,6 +5142,7 @@  static int bpf_core_fields_are_compat(const struct btf *local_btf,
 
 	switch (btf_kind(local_type)) {
 	case BTF_KIND_PTR:
+	case BTF_KIND_FLOAT:
 		return 1;
 	case BTF_KIND_FWD:
 	case BTF_KIND_ENUM: {
@@ -6245,8 +6247,8 @@  static int bpf_core_apply_relo(struct bpf_program *prog,
 	/* bpf_core_patch_insn() should know how to handle missing targ_spec */
 	err = bpf_core_patch_insn(prog, relo, relo_idx, &targ_res);
 	if (err) {
-		pr_warn("prog '%s': relo #%d: failed to patch insn at offset %d: %d\n",
-			prog->name, relo_idx, relo->insn_off, err);
+		pr_warn("prog '%s': relo #%d: failed to patch insn #%zu: %d\n",
+			prog->name, relo_idx, relo->insn_off / BPF_INSN_SZ, err);
 		return -EINVAL;
 	}