mk: disable gcc AVX512F support

This is a workaround to prevent a crash, which might be caused by
optimization of newer gcc (7.3.0) on Intel Skylake.

This disables AVX512F support of gcc by adding -mno-avx512f if it is
disabled in DPDK (CONFIG_RTE_ENABLE_AVX512=n).

This does not apply to the meson build as that doesn't have such an option
but always enable AVX512F whenever supported.

Bugzilla ID: 97
Cc: stable@dpdk.org
Signed-off-by: Yongseok Koh <yskoh@mellanox.com>

diff --git a/mk/rte.cpuflags.mk b/mk/rte.cpuflags.mk
index 43ed841..c3291b1 100644 (file)
--- a/mk/rte.cpuflags.mk
+++ b/mk/rte.cpuflags.mk
@@ -68,6 +68,11 @@ endif
 ifneq ($(filter $(AUTO_CPUFLAGS),__AVX512F__),)
 ifeq ($(CONFIG_RTE_ENABLE_AVX512),y)
 CPUFLAGS += AVX512F
+else
+# disable AVX512F support of gcc as a workaround for Bug 97
+ifeq ($(CONFIG_RTE_TOOLCHAIN_GCC),y)
+MACHINE_CFLAGS += -mno-avx512f
+endif
 endif
 endif