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From ff4f82816dff28ffaaff96d1409bb3811d345514 Mon Sep 17 00:00:00 2001
From: Fenghua Yu <fenghua.yu@intel.com>
Date: Tue, 15 Sep 2020 09:30:08 -0700
Subject: [PATCH] x86/cpufeatures: Enumerate ENQCMD and ENQCMDS instructions

References: jsc#SLE-13318
Patch-mainline: v5.10-rc1
Git-commit: ff4f82816dff28ffaaff96d1409bb3811d345514

Work submission instruction comes in two flavors. ENQCMD can be called
both in ring 3 and ring 0 and always uses the contents of a PASID MSR
when shipping the command to the device. ENQCMDS allows a kernel driver
to submit commands on behalf of a user process. The driver supplies the
PASID value in ENQCMDS. There isn't any usage of ENQCMD in the kernel as
of now.

The CPU feature flag is shown as "enqcmd" in /proc/cpuinfo.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/1600187413-163670-5-git-send-email-fenghua.yu@intel.com
---
 arch/x86/include/asm/cpufeatures.h | 1 +
 arch/x86/kernel/cpu/cpuid-deps.c   | 1 +
 2 files changed, 2 insertions(+)

diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 2901d5df4366..fea10d04d05f 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -353,6 +353,7 @@
 #define X86_FEATURE_CLDEMOTE		(16*32+25) /* CLDEMOTE instruction */
 #define X86_FEATURE_MOVDIRI		(16*32+27) /* MOVDIRI instruction */
 #define X86_FEATURE_MOVDIR64B		(16*32+28) /* MOVDIR64B instruction */
+#define X86_FEATURE_ENQCMD		(16*32+29) /* ENQCMD and ENQCMDS instructions */
 
 /* AMD-defined CPU features, CPUID level 0x80000007 (EBX), word 17 */
 #define X86_FEATURE_OVERFLOW_RECOV	(17*32+ 0) /* MCA overflow recovery support */
diff --git a/arch/x86/kernel/cpu/cpuid-deps.c b/arch/x86/kernel/cpu/cpuid-deps.c
--- a/arch/x86/kernel/cpu/cpuid-deps.c
+++ b/arch/x86/kernel/cpu/cpuid-deps.c
@@ -69,6 +69,7 @@ static const struct cpuid_dep cpuid_deps[] = {
 	{ X86_FEATURE_CQM_MBM_TOTAL,	X86_FEATURE_CQM_LLC   },
 	{ X86_FEATURE_CQM_MBM_LOCAL,	X86_FEATURE_CQM_LLC   },
 	{ X86_FEATURE_AVX512_BF16,	X86_FEATURE_AVX512VL  },
+	{ X86_FEATURE_ENQCMD,		X86_FEATURE_XSAVES    },
 	{}
 };
 
-- 
2.28.0