Hi Kazu,
On Mon, Nov 20, 2023 at 2:16 PM HAGIO KAZUHITO(萩尾 一仁)
<k-hagio-ab@xxxxxxx> wrote:
>
> On 2023/11/17 16:52, Tao Liu wrote:
>
> > For the stacktrace of "dis -rl", it calls dw2_expand_all_symtabs() to expand
> > all symtable of the objfile, or "*.ko.debug" in our case. However for
> > the stacktrace of "bt", it doesn't expand all, but only a subset of symtable
> > which is enough to find a symbol by dw2_lookup_symbol(). As a result, the
> > objfile->compunit_symtabs, which is the head of a single linked list of
> > struct compunit_symtab, is not NULL but didn't contain all symtables. It
> > will not be reinitialized in gdb_get_line_number() by "dis -rl" because
> > !objfile_has_full_symbols(objfile) check will fail, so it cannot display
> > the proper code line number data.
> >
> > Since objfile_has_full_symbols(objfile) check cannot ensure all symbols
> > been expanded, this patch add a new member as a flag for struct objfile
> > to record if all symbols have been expanded. The flag will be set only ofter
> > expand_all_symtabs been called.
>
> Thank you for the v2.
> Great, I can't think of any better way than this for now.
>
> Acked-by: Kazuhito Hagio <k-hagio-ab@xxxxxxx>
>
> (maybe I will reduce the commit log a bit when merging.)
>
Thanks a lot for the patch review. Please go ahead if the commit log
is too long.
Thanks,
Tao Liu
> Thanks,
> Kazu
>
> >
> > Signed-off-by: Tao Liu <ltao@xxxxxxxxxx>
> > ---
> > v1 -> v2: new method for kernel module symtabs expansion.
> > v1: expand all kernel modules symtabs when loading by mod -s/-S
> > v2: record if a specific kernel module's symtab been all expanded,
> > and skip re-expansion if true.
> > ---
> > gdb-10.2.patch | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 50 insertions(+)
> >
> > diff --git a/gdb-10.2.patch b/gdb-10.2.patch
> > index d81030d..2f7d585 100644
> > --- a/gdb-10.2.patch
> > +++ b/gdb-10.2.patch
> > @@ -3187,3 +3187,53 @@ exit 0
> > result = stringtab + symbol_entry->_n._n_n._n_offset;
> > }
> > else
> > +--- gdb-10.2/gdb/objfiles.h.orig
> > ++++ gdb-10.2/gdb/objfiles.h
> > +@@ -712,6 +712,8 @@ struct objfile
> > + next time. If an objfile does not have the symbols, it will
> > + never have them. */
> > + bool skip_jit_symbol_lookup = false;
> > ++
> > ++ bool all_symtabs_expanded = false;
> > + };
> > +
> > + /* A deleter for objfile. */
> > +--- gdb-10.2/gdb/symfile.c.orig
> > ++++ gdb-10.2/gdb/symfile.c
> > +@@ -1133,8 +1133,10 @@ symbol_file_add_with_addrs (bfd *abfd, const char *name,
> > + printf_filtered (_("Expanding full symbols from %ps...\n"),
> > + styled_string (file_name_style.style (), name));
> > +
> > +- if (objfile->sf)
> > ++ if (objfile->sf) {
> > + objfile->sf->qf->expand_all_symtabs (objfile);
> > ++ objfile->all_symtabs_expanded = true;
> > ++ }
> > + }
> > +
> > + /* Note that we only print a message if we have no symbols and have
> > +--- gdb-10.2/gdb/symtab.c.orig
> > ++++ gdb-10.2/gdb/symtab.c
> > +@@ -7097,8 +7097,9 @@ gdb_get_line_number(struct gnu_request *req)
> > + */
> > + if (req->lm) {
> > + objfile = req->lm->loaded_objfile;
> > +- if (!objfile_has_full_symbols(objfile) && objfile->sf) {
> > ++ if (!objfile->all_symtabs_expanded && objfile->sf) {
> > + objfile->sf->qf->expand_all_symtabs(objfile);
> > ++ objfile->all_symtabs_expanded = true;
> > + sal = find_pc_line(pc, 0);
> > + }
> > + }
> > +@@ -7761,8 +7765,10 @@ iterate_datatypes (struct gnu_request *req)
> > + {
> > + for (objfile *objfile : current_program_space->objfiles ())
> > + {
> > +- if (objfile->sf)
> > ++ if (objfile->sf) {
> > + objfile->sf->qf->expand_all_symtabs(objfile);
> > ++ objfile->all_symtabs_expanded = true;
> > ++ }
> > +
> > + for (compunit_symtab *cust : objfile->compunits ())
> > + {
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