[dpdk-stable] [PATCH v3] examples/l3fwd: fix unaligned memory access

[hgovindh <hariprasad.govindharajan@intel.com>]

Fix unaligned memory access when reading IPv6 header which
leads to segmentation fault by changing aligned memory read
to unaligned memory read.

Bugzilla ID: 279
Fixes: 64d3955de1de ("examples/l3fwd: fix ARM build")
Cc: maciej.czekaj@caviumnetworks.com
Cc: stable@dpdk.org
Signed-off-by: hgovindh <hariprasad.govindharajan@intel.com>
---
V2: Added functions which will do unaligned load based on the
underlying architecture

V3: Removed functions added in V2 and replaced them with if macros
which will branch based on the underlying architecture. As per my
understanding since the unaligned load affects only Intel arch,
I added that function branch and left the original code for other arc.
Can someone with ARM and PowerPC arch, could you please validate this
patch and let me know?
---
 examples/l3fwd/l3fwd_em.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/examples/l3fwd/l3fwd_em.c b/examples/l3fwd/l3fwd_em.c
index 5f499e005..ea9ca9491 100644
--- a/examples/l3fwd/l3fwd_em.c
+++ b/examples/l3fwd/l3fwd_em.c
@@ -244,6 +244,7 @@ em_mask_key(void *key, xmm_t mask)
 #error No vector engine (SSE, NEON, ALTIVEC) available, check your toolchain
 #endif
 
+
 static inline uint16_t
 em_get_ipv4_dst_port(void *ipv4_hdr, uint16_t portid, void *lookup_struct)
 {
@@ -287,8 +288,11 @@ em_get_ipv6_dst_port(void *ipv6_hdr, uint16_t portid, void *lookup_struct)
 	 * Get part of 5 tuple: dst IP address lower 96 bits
 	 * and src IP address higher 32 bits.
 	 */
+#if defined RTE_ARCH_X86
+	key.xmm[1] = _mm_loadu_si128(data1);
+#else
 	key.xmm[1] = *(xmm_t *)data1;
-
+#endif
 	/*
 	 * Get part of 5 tuple: dst port and src port
 	 * and dst IP address higher 32 bits.
-- 
2.22.0