From: Yu-cheng Yu <yu-cheng...@intel.com>

ENQCMD instruction reads PASID from IA32_PASID MSR. The MSR is stored
in the task's supervisor FPU PASID state and is context switched by
XSAVES/XRSTORS.

Signed-off-by: Yu-cheng Yu <yu-cheng...@intel.com>
Co-developed-by: Fenghua Yu <fenghua...@intel.com>
Signed-off-by: Fenghua Yu <fenghua...@intel.com>
Reviewed-by: Tony Luck <tony.l...@intel.com>
---
v2:
- Modify the commit message (Thomas)

 arch/x86/include/asm/fpu/types.h  | 11 ++++++++++-
 arch/x86/include/asm/fpu/xstate.h |  2 +-
 arch/x86/kernel/fpu/xstate.c      |  6 +++++-
 3 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/fpu/types.h b/arch/x86/include/asm/fpu/types.h
index c87364ea6446..f5a38a5f3ae1 100644
--- a/arch/x86/include/asm/fpu/types.h
+++ b/arch/x86/include/asm/fpu/types.h
@@ -114,7 +114,7 @@ enum xfeature {
        XFEATURE_Hi16_ZMM,
        XFEATURE_PT_UNIMPLEMENTED_SO_FAR,
        XFEATURE_PKRU,
-       XFEATURE_RSRVD_COMP_10,
+       XFEATURE_PASID,
        XFEATURE_RSRVD_COMP_11,
        XFEATURE_RSRVD_COMP_12,
        XFEATURE_RSRVD_COMP_13,
@@ -134,6 +134,7 @@ enum xfeature {
 #define XFEATURE_MASK_Hi16_ZMM         (1 << XFEATURE_Hi16_ZMM)
 #define XFEATURE_MASK_PT               (1 << XFEATURE_PT_UNIMPLEMENTED_SO_FAR)
 #define XFEATURE_MASK_PKRU             (1 << XFEATURE_PKRU)
+#define XFEATURE_MASK_PASID            (1 << XFEATURE_PASID)
 #define XFEATURE_MASK_LBR              (1 << XFEATURE_LBR)
 
 #define XFEATURE_MASK_FPSSE            (XFEATURE_MASK_FP | XFEATURE_MASK_SSE)
@@ -256,6 +257,14 @@ struct arch_lbr_state {
        struct lbr_entry                entries[];
 } __packed;
 
+/*
+ * State component 10 is supervisor state used for context-switching the
+ * PASID state.
+ */
+struct ia32_pasid_state {
+       u64 pasid;
+} __packed;
+
 struct xstate_header {
        u64                             xfeatures;
        u64                             xcomp_bv;
diff --git a/arch/x86/include/asm/fpu/xstate.h 
b/arch/x86/include/asm/fpu/xstate.h
index 14ab815132d4..47a92232d595 100644
--- a/arch/x86/include/asm/fpu/xstate.h
+++ b/arch/x86/include/asm/fpu/xstate.h
@@ -35,7 +35,7 @@
                                      XFEATURE_MASK_BNDCSR)
 
 /* All currently supported supervisor features */
-#define XFEATURE_MASK_SUPERVISOR_SUPPORTED (0)
+#define XFEATURE_MASK_SUPERVISOR_SUPPORTED (XFEATURE_MASK_PASID)
 
 /*
  * A supervisor state component may not always contain valuable information,
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index 038e19c0019e..67f1a03b9b23 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -37,6 +37,7 @@ static const char *xfeature_names[] =
        "AVX-512 ZMM_Hi256"             ,
        "Processor Trace (unused)"      ,
        "Protection Keys User registers",
+       "PASID state",
        "unknown xstate feature"        ,
 };
 
@@ -51,6 +52,7 @@ static short xsave_cpuid_features[] __initdata = {
        X86_FEATURE_AVX512F,
        X86_FEATURE_INTEL_PT,
        X86_FEATURE_PKU,
+       X86_FEATURE_ENQCMD,
 };
 
 /*
@@ -318,6 +320,7 @@ static void __init print_xstate_features(void)
        print_xstate_feature(XFEATURE_MASK_ZMM_Hi256);
        print_xstate_feature(XFEATURE_MASK_Hi16_ZMM);
        print_xstate_feature(XFEATURE_MASK_PKRU);
+       print_xstate_feature(XFEATURE_MASK_PASID);
 }
 
 /*
@@ -592,6 +595,7 @@ static void check_xstate_against_struct(int nr)
        XCHECK_SZ(sz, nr, XFEATURE_ZMM_Hi256, struct avx_512_zmm_uppers_state);
        XCHECK_SZ(sz, nr, XFEATURE_Hi16_ZMM,  struct avx_512_hi16_state);
        XCHECK_SZ(sz, nr, XFEATURE_PKRU,      struct pkru_state);
+       XCHECK_SZ(sz, nr, XFEATURE_PASID,     struct ia32_pasid_state);
 
        /*
         * Make *SURE* to add any feature numbers in below if
@@ -601,7 +605,7 @@ static void check_xstate_against_struct(int nr)
        if ((nr < XFEATURE_YMM) ||
            (nr >= XFEATURE_MAX) ||
            (nr == XFEATURE_PT_UNIMPLEMENTED_SO_FAR) ||
-           ((nr >= XFEATURE_RSRVD_COMP_10) && (nr <= XFEATURE_LBR))) {
+           ((nr >= XFEATURE_RSRVD_COMP_11) && (nr <= XFEATURE_LBR))) {
                WARN_ONCE(1, "no structure for xstate: %d\n", nr);
                XSTATE_WARN_ON(1);
        }
-- 
2.19.1

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