[dpdk-stable] [PATCH v2 1/2] eal/x86: fix some CPU extended features definitions

David Marchand david.marchand at redhat.com
Fri Oct 8 14:07:14 CEST 2021


Caught while checking CPUID related stuff in OVS.

According to [1], for Structured Extended Feature Flags Enumeration Leaf
(EAX = 0x07H, ECX = 0):

- BMI1 is associated to EBX, bit 3 (was incorrectly 2),
- SMEP is associated to EBX, bit 7 (was incorrectly 6),
- BMI2 is associated to EBX, bit 8 (was incorrectly 7),
- ERMS is associated to EBX, bit 9 (was incorrectly 8),

1: https://software.intel.com/sites/default/files/managed/c5/15/architecture-instruction-set-extensions-programming-reference.pdf

Fixes: af75078fece3 ("first public release")
Cc: stable at dpdk.org

Signed-off-by: David Marchand <david.marchand at redhat.com>
Acked-by: Bruce Richardson <bruce.richardson at intel.com>
---
 lib/eal/x86/rte_cpuflags.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/eal/x86/rte_cpuflags.c b/lib/eal/x86/rte_cpuflags.c
index d339734a8c..378fc95396 100644
--- a/lib/eal/x86/rte_cpuflags.c
+++ b/lib/eal/x86/rte_cpuflags.c
@@ -100,12 +100,12 @@ const struct feature_entry rte_cpu_feature_table[] = {
 	FEAT_DEF(ENERGY_EFF, 0x00000006, 0, RTE_REG_ECX,  3)
 
 	FEAT_DEF(FSGSBASE, 0x00000007, 0, RTE_REG_EBX,  0)
-	FEAT_DEF(BMI1, 0x00000007, 0, RTE_REG_EBX,  2)
+	FEAT_DEF(BMI1, 0x00000007, 0, RTE_REG_EBX,  3)
 	FEAT_DEF(HLE, 0x00000007, 0, RTE_REG_EBX,  4)
 	FEAT_DEF(AVX2, 0x00000007, 0, RTE_REG_EBX,  5)
-	FEAT_DEF(SMEP, 0x00000007, 0, RTE_REG_EBX,  6)
-	FEAT_DEF(BMI2, 0x00000007, 0, RTE_REG_EBX,  7)
-	FEAT_DEF(ERMS, 0x00000007, 0, RTE_REG_EBX,  8)
+	FEAT_DEF(SMEP, 0x00000007, 0, RTE_REG_EBX,  7)
+	FEAT_DEF(BMI2, 0x00000007, 0, RTE_REG_EBX,  8)
+	FEAT_DEF(ERMS, 0x00000007, 0, RTE_REG_EBX,  9)
 	FEAT_DEF(INVPCID, 0x00000007, 0, RTE_REG_EBX, 10)
 	FEAT_DEF(RTM, 0x00000007, 0, RTE_REG_EBX, 11)
 	FEAT_DEF(AVX512F, 0x00000007, 0, RTE_REG_EBX, 16)
-- 
2.23.0



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