[dpdk-dev] [PATCH] eal: disable IOVA mode detection by default

[Ferruh Yigit <ferruh.yigit@intel.com>]

Fix kernel crash with KNI because KNI requires physical addresses.

A config option introduced to disable IOVA mode detection and to set it
to physical address by default. Disabling config option will enable IOVA
mode detection.

When there is no intension to use KNI, it is safe to enable detection.

Config option disable IOVA mode detection by default to be sure only who
is aware of result enable it.

Fixes: 72d013644bd6 ("mem: honor IOVA mode in malloc virt2phy")

Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
---
Cc: Jianfeng Tan <jianfeng.tan@intel.com>
Cc: Santosh Shukla <santosh.shukla@caviumnetworks.com>
Cc: Thomas Monjalon <thomas@monjalon.net>
---
 config/common_base                | 5 +++++
 lib/librte_eal/bsdapp/eal/eal.c   | 4 ++++
 lib/librte_eal/linuxapp/eal/eal.c | 4 ++++
 3 files changed, 13 insertions(+)

diff --git a/config/common_base b/config/common_base
index 82ee75456..903e7685b 100644
--- a/config/common_base
+++ b/config/common_base
@@ -107,6 +107,11 @@ CONFIG_RTE_MALLOC_DEBUG=n
 CONFIG_RTE_EAL_NUMA_AWARE_HUGEPAGES=n
 
 #
+# Disabling PHYS_IOVA may crash kernel for KNI, use with caution
+#
+CONFIG_RTE_EAL_USE_PHYS_IOVA=y
+
+#
 # Recognize/ignore the AVX/AVX512 CPU flags for performance/power testing.
 # AVX512 is marked as experimental for now, will enable it after enough
 # field test and possible optimization.
diff --git a/lib/librte_eal/bsdapp/eal/eal.c b/lib/librte_eal/bsdapp/eal/eal.c
index 09112b6f9..db485951b 100644
--- a/lib/librte_eal/bsdapp/eal/eal.c
+++ b/lib/librte_eal/bsdapp/eal/eal.c
@@ -570,8 +570,12 @@ rte_eal_init(int argc, char **argv)
 		return -1;
 	}
 
+#ifdef RTE_EAL_USE_PHYS_IOVA
+	rte_eal_get_configuration()->iova_mode = RTE_IOVA_PA;
+#else
 	/* autodetect the iova mapping mode (default is iova_pa) */
 	rte_eal_get_configuration()->iova_mode = rte_bus_get_iommu_class();
+#endif
 
 	if (internal_config.no_hugetlbfs == 0 &&
 			internal_config.process_type != RTE_PROC_SECONDARY &&
diff --git a/lib/librte_eal/linuxapp/eal/eal.c b/lib/librte_eal/linuxapp/eal/eal.c
index 017c402ed..1775bb33f 100644
--- a/lib/librte_eal/linuxapp/eal/eal.c
+++ b/lib/librte_eal/linuxapp/eal/eal.c
@@ -805,8 +805,12 @@ rte_eal_init(int argc, char **argv)
 		return -1;
 	}
 
+#ifdef RTE_EAL_USE_PHYS_IOVA
+	rte_eal_get_configuration()->iova_mode = RTE_IOVA_PA;
+#else
 	/* autodetect the iova mapping mode (default is iova_pa) */
 	rte_eal_get_configuration()->iova_mode = rte_bus_get_iommu_class();
+#endif
 
 	if (internal_config.no_hugetlbfs == 0 &&
 			internal_config.process_type != RTE_PROC_SECONDARY &&
-- 
2.13.6