Keep all function symbols in the vDSO .symtab for stack trace purposes.
This enables perf to lookup these function symbols in addition to those
already exported in vDSO .dynsym.
Signed-off-by: Jens Remus <jre...@linux.ibm.com>
---
Notes (jremus):
Alternatively use objcopy option -g instead of -S (and the -w -K
filters), as Josh did in "x86/vdso: Enable sframe generation in VDSO":
https://lore.kernel.org/all/20250425024023.173709...@goodmis.org/
Note that this change does not cause the vDSO build-id to change.
perf record may therefore not dump an updated copy of the vDSO to
~/.debug/[vdso]/<build-id>/vdso, so that perf script may use a
stale copy without .symtab. Resolve by deleting ~/.debug/.
arch/s390/kernel/vdso64/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/s390/kernel/vdso64/Makefile b/arch/s390/kernel/vdso64/Makefile
index e96156b9c4df..067753352697 100644
--- a/arch/s390/kernel/vdso64/Makefile
+++ b/arch/s390/kernel/vdso64/Makefile
@@ -58,7 +58,7 @@ $(obj)/vdso64.so.dbg: $(obj)/vdso64.lds $(obj-vdso64)
$(obj-cvdso64) FORCE
$(call if_changed,vdso_and_check)
# strip rule for the .so file
-$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: OBJCOPYFLAGS := -S -w -K "__arch_*" -K "__cvdso_*" -K
"__s390_vdso_*"
$(obj)/%.so: $(obj)/%.so.dbg FORCE
$(call if_changed,objcopy)
--
2.48.1
