Le 17/08/2021 à 15:02, Jan Stancek a écrit :
gcov and kasan rely on compiler generated constructor code.
For modules, gcc-8 with gcov enabled generates .init_array section,
but on ppc64le it doesn't get executed. find_module_sections() never
finds .init_array section, because module_frob_arch_sections() renames
it to _init_array.
Avoid renaming .init_array section, so do_mod_ctors() can use it.
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Cc: Paul Mackerras <pau...@samba.org>
Cc: Christophe Leroy <christophe.le...@csgroup.eu>
Signed-off-by: Jan Stancek <jstan...@redhat.com>
Does commit d4be60fe66b7 ("powerpc/module_64: use module_init_section
instead of patching names") fixes your issue ?
If not, please rebase and resubmit.
Thanks
Christophe
---
I wasn't able to trace the comment:
"We don't handle .init for the moment: rename to _init"
to original patch (it pre-dates .git). I'm not sure if it
still applies today, so I limited patch to .init_array. This
fixes gcov for modules for me on ppc64le 5.14.0-rc6.
Renaming issue is also mentioned in kasan patches here:
https://patchwork.ozlabs.org/project/linuxppc-dev/cover/20210319144058.772525-1-dja@axtens
arch/powerpc/kernel/module_64.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c
index 6baa676e7cb6..c604b13ea6bf 100644
--- a/arch/powerpc/kernel/module_64.c
+++ b/arch/powerpc/kernel/module_64.c
@@ -299,8 +299,16 @@ int module_frob_arch_sections(Elf64_Ehdr *hdr,
sechdrs[i].sh_size);
/* We don't handle .init for the moment: rename to _init */
- while ((p = strstr(secstrings + sechdrs[i].sh_name, ".init")))
+ while ((p = strstr(secstrings + sechdrs[i].sh_name, ".init"))) {
+#ifdef CONFIG_CONSTRUCTORS
+ /* find_module_sections() needs .init_array intact */
+ if (strstr(secstrings + sechdrs[i].sh_name,
+ ".init_array")) {
+ break;
+ }
+#endif
p[0] = '_';
+ }
if (sechdrs[i].sh_type == SHT_SYMTAB)
dedotify((void *)hdr + sechdrs[i].sh_offset,
