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There are two >> ways to resolve this issue. >> (1). If btf encoding is expected, remove all dwarf int types >> where btf encoding will failure, e.g., non-power-of-2 >> bytes, or greater than 16 bytes. >> (2). do a sanitization in btf_encoder ([2]). >> >> This patch uses method (2) since it is a simple fix in btf_encoder. >> I checked my local built vmlinux with latest >> bpf-next. There is only one instance of DW_ATE_unsigned_24 (used in >> DW_AT_location) so I expect irregular int types should be very rare. >> >> [1] https://github.com/libbpf/libbpf/pull/680 >> [2] commit 7d8e829f636f ("btf_encoder: Sanitize non-regular int base type") >> >> Signed-off-by: Yonghong Song > > Thanks, this fixed the above reported error for me. My report is just > forwarded from Satya. > > Reported-by: Satya Durga Srinivasu Prabhala > Tested-by: Nick Desaulniers > > I don't know if that change has other implications for unusual byte sizes. > > We might need to consider at some point waiting to validate > DW_TAG_base_type until we know that they're not used outside of > DW_AT_location expressions. David Blaikie confirmed that indeed special types like DW_ATE_unsigned_1024 is indeed generated for DW_AT_location. See https://github.com/libbpf/libbpf/pull/680 for details. > >> --- >> btf_encoder.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/btf_encoder.c b/btf_encoder.c >> index 65f6e71..1aa0ad0 100644 >> --- a/btf_encoder.c >> +++ b/btf_encoder.c >> @@ -394,7 +394,7 @@ static int32_t btf_encoder__add_base_type(struct btf_encoder *encoder, const str >> * these non-regular int types to avoid libbpf/kernel complaints. >> */ >> byte_sz = BITS_ROUNDUP_BYTES(bt->bit_size); >> - if (!byte_sz || (byte_sz & (byte_sz - 1))) { >> + if (!byte_sz || (byte_sz & (byte_sz - 1)) || byte_sz > 16) { >> name = "__SANITIZED_FAKE_INT__"; >> byte_sz = 4; >> } >> -- >> 2.34.1 >> > >