[dpdk-stable] patch 'mk: disable gcc AVX512F support' has been queued to LTS release 16.11.9

[Luca Boccassi]

Hi,

FYI, your patch has been queued to LTS release 16.11.9

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 11/10/18. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the patch applied
to the branch. If the code is different (ie: not only metadata diffs), due for example to
a change in context or macro names, please double check it.

Thanks.

Luca Boccassi

---
>From 8dbda3ba255c6045ffe3eb73f1d8e1f67186c22b Mon Sep 17 00:00:00 2001
From: Yongseok Koh <yskoh at mellanox.com>
Date: Sat, 3 Nov 2018 01:06:32 +0000
Subject: [PATCH] mk: disable gcc AVX512F support

[ upstream commit 8d07c82b239f7782be0d3afbb626390e2cb0c8f5 ]

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

Signed-off-by: Yongseok Koh <yskoh at mellanox.com>
---
 mk/rte.cpuflags.mk | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/mk/rte.cpuflags.mk b/mk/rte.cpuflags.mk
index 8bbccb9ed..c7027a0fe 100644
--- a/mk/rte.cpuflags.mk
+++ b/mk/rte.cpuflags.mk
@@ -91,6 +91,11 @@ endif
 
 ifneq ($(filter $(AUTO_CPUFLAGS),__AVX512F__),)
 CPUFLAGS += AVX512F
+else
+# disable AVX512F support of gcc as a workaround for Bug 97
+ifeq ($(CONFIG_RTE_TOOLCHAIN_GCC),y)
+MACHINE_CFLAGS += -mno-avx512f
+endif
 endif
 
 # IBM Power CPU flags
-- 
2.19.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2018-11-08 17:59:30.124667578 +0000
+++ 0003-mk-disable-gcc-AVX512F-support.patch	2018-11-08 17:59:30.048751011 +0000
@@ -1,8 +1,10 @@
-From 8d07c82b239f7782be0d3afbb626390e2cb0c8f5 Mon Sep 17 00:00:00 2001
+From 8dbda3ba255c6045ffe3eb73f1d8e1f67186c22b Mon Sep 17 00:00:00 2001
 From: Yongseok Koh <yskoh at mellanox.com>
 Date: Sat, 3 Nov 2018 01:06:32 +0000
 Subject: [PATCH] mk: disable gcc AVX512F support
 
+[ upstream commit 8d07c82b239f7782be0d3afbb626390e2cb0c8f5 ]
+
 This is a workaround to prevent a crash, which might be caused by
 optimization of newer gcc (7.3.0) on Intel Skylake.
 
@@ -13,7 +15,6 @@
 but always enable AVX512F whenever supported.
 
 Bugzilla ID: 97
-Cc: stable at dpdk.org
 
 Signed-off-by: Yongseok Koh <yskoh at mellanox.com>
 ---
@@ -21,12 +22,12 @@
  1 file changed, 5 insertions(+)
 
 diff --git a/mk/rte.cpuflags.mk b/mk/rte.cpuflags.mk
-index 43ed84155..c3291b17a 100644
+index 8bbccb9ed..c7027a0fe 100644
 --- a/mk/rte.cpuflags.mk
 +++ b/mk/rte.cpuflags.mk
-@@ -68,6 +68,11 @@ endif
+@@ -91,6 +91,11 @@ 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
@@ -34,8 +35,8 @@
 +MACHINE_CFLAGS += -mno-avx512f
 +endif
  endif
- endif
  
+ # IBM Power CPU flags
 -- 
 2.19.1