The `Data` and `Code` flags in `qOffsets` are actually section offsets rather than segment offsets. GDB relocates the symbols in those sections relative to their location in the binary. So we have to use `load_bias`.
See here for a more detailed description: https://sourceware.org/gdb/onlinedocs/gdb/General-Query-Packets.html#General-Query-Packets On Mon, Aug 26, 2019 at 1:29 AM Laurent Vivier <laur...@vivier.eu> wrote: > Le 17/08/2019 à 01:34, Josh Kunz via Qemu-devel a écrit : > > This is needed to support debugging PIE ELF binaries running under QEMU > > user mode. Currently, `code_offset` and `data_offset` remain unset for > > all ELF binaries, so GDB is unable to correctly locate the position of > > the binary's text and data. > > > > The fields `code_offset`, and `data_offset` were originally added way > > back in 2006 to support debugging of bFMT executables (978efd6aac6), > > and support was just never added for ELF. Since non-PIE binaries are > > loaded at exactly the address specified in the binary, GDB does not need > > to relocate any symbols, so the buggy behavior is not normally observed. > > > > Buglink: https://bugs.launchpad.net/qemu/+bug/1528239 > > Signed-off-by: Josh Kunz <j...@google.com> > > --- > > linux-user/elfload.c | 2 ++ > > 1 file changed, 2 insertions(+) > > As it seems they are text and data segment offsets, why it's not based > on info->start_code and info->start_data? > > Thanks, > Laurent >
