[PATCH] powerpc: Fix BPF_JIT code to link with multiple TOCs

[Michael Ellerman]

If the kernel is big enough (eg. allyesconfig), the linker may need to
switch TOCs when calling from the BPF JIT code out to the external
helpers (skb_copy_bits() & bpf_internal_load_pointer_neg_helper()).

In order to do that we need to leave space after the bl for the linker
to insert a reload of our TOC pointer.

Signed-off-by: Michael Ellerman <michael at ellerman.id.au>
---
 arch/powerpc/net/bpf_jit_64.S |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/net/bpf_jit_64.S b/arch/powerpc/net/bpf_jit_64.S
index 55ba385..7d3a3b5 100644
--- a/arch/powerpc/net/bpf_jit_64.S
+++ b/arch/powerpc/net/bpf_jit_64.S
@@ -105,6 +105,7 @@ sk_load_byte_msh_positive_offset:
 	mr	r4, r_addr;					\
 	li	r6, SIZE;					\
 	bl	skb_copy_bits;					\
+	nop;							\
 	/* R3 = 0 on success */					\
 	addi	r1, r1, BPF_PPC_SLOWPATH_FRAME;			\
 	ld	r0, 16(r1);					\
@@ -156,6 +157,7 @@ bpf_slow_path_byte_msh:
 	mr	r4, r_addr;					\
 	li	r5, SIZE;					\
 	bl	bpf_internal_load_pointer_neg_helper;		\
+	nop;							\
 	/* R3 != 0 on success */				\
 	addi	r1, r1, BPF_PPC_SLOWPATH_FRAME;			\
 	ld	r0, 16(r1);					\
-- 
1.7.9.5