From: Andi Kleen <[email protected]> Disable LTO for the BPF interpreter. This works around a gcc bug in the LTO partitioner that partitions the jumptable used the BPF interpreter into a different LTO unit. This in term causes assembler errors because the jump table contains references to the code labels in the original file.
gcc problem tracked in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=50676 Signed-off-by: Andi Kleen <[email protected]> --- kernel/bpf/Makefile | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index e691da0b3bab..409d4b6762ee 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -16,3 +16,8 @@ ifeq ($(CONFIG_PERF_EVENTS),y) obj-$(CONFIG_BPF_SYSCALL) += stackmap.o endif obj-$(CONFIG_CGROUP_BPF) += cgroup.o + +# various version of gcc have a LTO bug where the &&labels used in the +# BPF interpreter can cause linker errors when spread incorrectly over +# partitions. Disable LTO for BPF for now +CFLAGS_core.o = $(DISABLE_LTO) -- 2.13.6
