Subject: [PATCH 2/2] powerpc: bpf: Fix the broken LD_VLAN_TAG_PRESENT test

From: Denis Kirjanov <[email-masked]>
Date: Tue, 24 Jun 2014 13:59:29 +0400

We have to return the boolean here if the tag presents
or not, not jusr ORing the TCI with the mask which results to:

[  709.412097] test_bpf: #18 LD_VLAN_TAG_PRESENT
[  709.412245] ret 4096 != 1
[  709.412332] ret 4096 != 1
[  709.412333] FAIL (2 times)
---
 arch/powerpc/net/bpf_jit_comp.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index af0ed4d..a3d8f58 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -394,8 +394,10 @@ static int bpf_jit_build_body(struct sk_filter *fp, u32 *image,
 							  vlan_tci));
 			if (code == (BPF_ANC | SKF_AD_VLAN_TAG))
 				PPC_ANDI(r_A, r_A, ~VLAN_TAG_PRESENT);
-			else
+			else {
 				PPC_ANDI(r_A, r_A, VLAN_TAG_PRESENT);
+				PPC_SRWI(r_A, r_A, 12);
+			}
 			break;
 		case BPF_ANC | SKF_AD_QUEUE:
 			BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff,
-- 
2.0.0