From: "H.J. Lu" <hjl.tools@xxxxxxxxx> When Indirect Branch Tracking (IBT) is enabled, vDSO functions may be called indirectly, and must have ENDBR32 or ENDBR64 as the first instruction. The compiler must support -fcf-protection=branch so that it can be used to compile vDSO. Signed-off-by: H.J. Lu <hjl.tools@xxxxxxxxx> Signed-off-by: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx> Acked-by: Andy Lutomirski <luto@xxxxxxxxxx> --- arch/x86/entry/vdso/Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index 215376d975a2..82f8e25e139f 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -130,6 +130,10 @@ $(obj)/%-x32.o: $(obj)/%.o FORCE targets += vdsox32.lds $(vobjx32s-y) +ifdef CONFIG_X86_INTEL_BRANCH_TRACKING_USER + $(obj)/vclock_gettime.o $(obj)/vgetcpu.o $(obj)/vdso32/vclock_gettime.o: KBUILD_CFLAGS += -fcf-protection=branch +endif + $(obj)/%.so: OBJCOPYFLAGS := -S $(obj)/%.so: $(obj)/%.so.dbg FORCE $(call if_changed,objcopy) -- 2.21.0
