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Leon Hwang caf27ed9ea bpf, bpftool: Fix incorrect disasm pc

[ Upstream commit 4d99e509c1 ]

This patch addresses the bpftool issue "Wrong callq address displayed"[0].

The issue stemmed from an incorrect program counter (PC) value used during
disassembly with LLVM or libbfd.

For LLVM: The PC argument must represent the actual address in the kernel
to compute the correct relative address.

For libbfd: The relative address can be adjusted by adding func_ksym within
the custom info->print_address_func to yield the correct address.

Links:
[0] https://github.com/libbpf/bpftool/issues/109

Changes:
v2 -> v3:
  * Address comment from Quentin:
    * Remove the typedef.

v1 -> v2:
  * Fix the broken libbfd disassembler.

Fixes: e1947c750f ("bpftool: Refactor disassembler for JIT-ed programs")
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Quentin Monnet <qmo@kernel.org>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/bpf/20241031152844.68817-1-leon.hwang@linux.dev
Signed-off-by: Sasha Levin <sashal@kernel.org>