x86/cpufeatures: Enumerate ENQCMD and ENQCMDS instructions

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

diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 2901d5df4366c0409e6d295d0eb1585aa1568ea9..fea10d04d05f579712538925d33f1152e7493445 100644 (file)
--- 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
index 3cbe24ca80abd9b1033657a080da305e29d31a3c..3a02707c1f4d0b5be08f38e83e58a8d23b6d6b1b 100644 (file)
--- 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    },
        {}
 };