[Xen-devel] [PATCH 0/6] x86emul: further work

Jan Beulich posted 6 patches 2 weeks ago
Only 0 patches received!

[Xen-devel] [PATCH 0/6] x86emul: further work

Posted by Jan Beulich 2 weeks ago
On top of the AVX512 series I'd like to put out for review/discussion

1: generalize wbinvd() hook
2: support WBNOINVD
3: generalize invlpg() hook
4: move INVPCID_TYPE_* to x86-defns.h
5: support INVPCID
6: support MOVDIR{I,64B} insns

Jan
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[Xen-devel] [PATCH 1/6] x86emul: generalize wbinvd() hook

Posted by Jan Beulich 2 weeks ago
The hook is already in use for other purposes, and emulating e.g.
CLFLUSH by issuing WBINVD is, well, not very nice. Rename the hook and
add parameters. Use lighter weight flushing insns when possible in
hvmemul_cache_op().

hvmemul_cache_op() treating x86emul_invd the same as x86emul_wbinvd is
to retain original behavior, but I'm not sure this is what we want in
the long run.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
v2: Use cache_op() as hook name. Convert macros to inline functions in
     system.h. Re-base.
---
I was unsure about PREFETCH* and CLDEMOTE - both are cache management
insns too, but the emulator currently treats them as a NOP without
invoking any hooks.
I was also uncertain about the new cache_flush_permitted() instance -
generally I think it wouldn't be too bad if we allowed line flushes in
all cases, in which case the checks in the ->wbinvd_intercept() handlers
would suffice (as they did until now).

--- a/tools/fuzz/x86_instruction_emulator/fuzz-emul.c
+++ b/tools/fuzz/x86_instruction_emulator/fuzz-emul.c
@@ -382,10 +382,13 @@ static int fuzz_invlpg(
      return maybe_fail(ctxt, "invlpg", false);
  }
  
-static int fuzz_wbinvd(
+static int fuzz_cache_op(
+    enum x86emul_cache_op op,
+    enum x86_segment seg,
+    unsigned long offset,
      struct x86_emulate_ctxt *ctxt)
  {
-    return maybe_fail(ctxt, "wbinvd", true);
+    return maybe_fail(ctxt, "cache-management", true);
  }
  
  static int fuzz_write_io(
@@ -620,7 +623,7 @@ static const struct x86_emulate_ops all_
      SET(read_xcr),
      SET(read_msr),
      SET(write_msr),
-    SET(wbinvd),
+    SET(cache_op),
      SET(invlpg),
      .get_fpu    = emul_test_get_fpu,
      .put_fpu    = emul_test_put_fpu,
@@ -729,7 +732,7 @@ enum {
      HOOK_read_xcr,
      HOOK_read_msr,
      HOOK_write_msr,
-    HOOK_wbinvd,
+    HOOK_cache_op,
      HOOK_cpuid,
      HOOK_inject_hw_exception,
      HOOK_inject_sw_interrupt,
@@ -773,7 +776,7 @@ static void disable_hooks(struct x86_emu
      MAYBE_DISABLE_HOOK(read_xcr);
      MAYBE_DISABLE_HOOK(read_msr);
      MAYBE_DISABLE_HOOK(write_msr);
-    MAYBE_DISABLE_HOOK(wbinvd);
+    MAYBE_DISABLE_HOOK(cache_op);
      MAYBE_DISABLE_HOOK(cpuid);
      MAYBE_DISABLE_HOOK(get_fpu);
      MAYBE_DISABLE_HOOK(invlpg);
--- a/xen/arch/x86/Rules.mk
+++ b/xen/arch/x86/Rules.mk
@@ -19,7 +19,9 @@ $(call as-option-add,CFLAGS,CC,"crc32 %e
  $(call as-option-add,CFLAGS,CC,"invept (%rax)$$(comma)%rax",-DHAVE_AS_EPT)
  $(call as-option-add,CFLAGS,CC,"rdrand %eax",-DHAVE_AS_RDRAND)
  $(call as-option-add,CFLAGS,CC,"rdfsbase %rax",-DHAVE_AS_FSGSBASE)
+$(call as-option-add,CFLAGS,CC,"xsaveopt (%rax)",-DHAVE_AS_XSAVEOPT)
  $(call as-option-add,CFLAGS,CC,"rdseed %eax",-DHAVE_AS_RDSEED)
+$(call as-option-add,CFLAGS,CC,"clwb (%rax)",-DHAVE_AS_CLWB)
  $(call as-option-add,CFLAGS,CC,".equ \"x\"$$(comma)1", \
                       -U__OBJECT_LABEL__ -DHAVE_AS_QUOTED_SYM \
                       '-D__OBJECT_LABEL__=$(subst $(BASEDIR)/,,$(CURDIR))/$$@')
--- a/xen/arch/x86/hvm/emulate.c
+++ b/xen/arch/x86/hvm/emulate.c
@@ -25,6 +25,7 @@
  #include <asm/hvm/trace.h>
  #include <asm/hvm/support.h>
  #include <asm/hvm/svm/svm.h>
+#include <asm/iocap.h>
  #include <asm/vm_event.h>
  
  static void hvmtrace_io_assist(const ioreq_t *p)
@@ -555,16 +556,12 @@ static void *hvmemul_map_linear_addr(
      mfn_t *mfn = &hvmemul_ctxt->mfn[0];
  
      /*
-     * The caller has no legitimate reason for trying a zero-byte write, but
-     * all other code here is written to work if the check below was dropped.
-     *
-     * The maximum write size depends on the number of adjacent mfns[] which
+     * The maximum access size depends on the number of adjacent mfns[] which
       * can be vmap()'d, accouting for possible misalignment within the region.
       * The higher level emulation callers are responsible for ensuring that
-     * mfns[] is large enough for the requested write size.
+     * mfns[] is large enough for the requested access size.
       */
-    if ( bytes == 0 ||
-         nr_frames > ARRAY_SIZE(hvmemul_ctxt->mfn) )
+    if ( nr_frames > ARRAY_SIZE(hvmemul_ctxt->mfn) )
      {
          ASSERT_UNREACHABLE();
          goto unhandleable;
@@ -669,8 +666,6 @@ static void hvmemul_unmap_linear_addr(
      unsigned int i;
      mfn_t *mfn = &hvmemul_ctxt->mfn[0];
  
-    ASSERT(bytes > 0);
-
      if ( nr_frames == 1 )
          unmap_domain_page(mapping);
      else
@@ -1473,7 +1468,10 @@ static int hvmemul_write_msr_discard(
      return X86EMUL_OKAY;
  }
  
-static int hvmemul_wbinvd_discard(
+static int hvmemul_cache_op_discard(
+    enum x86emul_cache_op op,
+    enum x86_segment seg,
+    unsigned long offset,
      struct x86_emulate_ctxt *ctxt)
  {
      return X86EMUL_OKAY;
@@ -2149,10 +2147,65 @@ static int hvmemul_write_msr(
      return rc;
  }
  
-static int hvmemul_wbinvd(
+static int hvmemul_cache_op(
+    enum x86emul_cache_op op,
+    enum x86_segment seg,
+    unsigned long offset,
      struct x86_emulate_ctxt *ctxt)
  {
-    alternative_vcall(hvm_funcs.wbinvd_intercept);
+    struct hvm_emulate_ctxt *hvmemul_ctxt =
+        container_of(ctxt, struct hvm_emulate_ctxt, ctxt);
+    unsigned long addr, reps = 1;
+    uint32_t pfec = PFEC_page_present;
+    int rc;
+    void *mapping;
+
+    if ( !cache_flush_permitted(current->domain) )
+        return X86EMUL_OKAY;
+
+    switch ( op )
+    {
+    case x86emul_clflush:
+    case x86emul_clflushopt:
+    case x86emul_clwb:
+        ASSERT(!is_x86_system_segment(seg));
+
+        rc = hvmemul_virtual_to_linear(seg, offset, 0, &reps,
+                                       hvm_access_read, hvmemul_ctxt, &addr);
+        if ( rc != X86EMUL_OKAY )
+            break;
+
+        if ( hvmemul_ctxt->seg_reg[x86_seg_ss].dpl == 3 )
+            pfec |= PFEC_user_mode;
+
+        mapping = hvmemul_map_linear_addr(addr, 0, pfec, hvmemul_ctxt,
+                                          current->arch.hvm.data_cache);
+        if ( mapping == ERR_PTR(~X86EMUL_EXCEPTION) )
+            return X86EMUL_EXCEPTION;
+        if ( IS_ERR_OR_NULL(mapping) )
+            break;
+
+        if ( cpu_has_clflush )
+        {
+            if ( op == x86emul_clwb && cpu_has_clwb )
+                clwb(mapping);
+            else if ( op == x86emul_clflushopt && cpu_has_clflushopt )
+                clflushopt(mapping);
+            else
+                clflush(mapping);
+
+            hvmemul_unmap_linear_addr(mapping, addr, 0, hvmemul_ctxt);
+            break;
+        }
+
+        hvmemul_unmap_linear_addr(mapping, addr, 0, hvmemul_ctxt);
+        /* fall through */
+    case x86emul_invd:
+    case x86emul_wbinvd:
+        alternative_vcall(hvm_funcs.wbinvd_intercept);
+        break;
+    }
+
      return X86EMUL_OKAY;
  }
  
@@ -2353,7 +2406,7 @@ static const struct x86_emulate_ops hvm_
      .write_xcr     = hvmemul_write_xcr,
      .read_msr      = hvmemul_read_msr,
      .write_msr     = hvmemul_write_msr,
-    .wbinvd        = hvmemul_wbinvd,
+    .cache_op      = hvmemul_cache_op,
      .cpuid         = x86emul_cpuid,
      .get_fpu       = hvmemul_get_fpu,
      .put_fpu       = hvmemul_put_fpu,
@@ -2380,7 +2433,7 @@ static const struct x86_emulate_ops hvm_
      .write_xcr     = hvmemul_write_xcr,
      .read_msr      = hvmemul_read_msr,
      .write_msr     = hvmemul_write_msr_discard,
-    .wbinvd        = hvmemul_wbinvd_discard,
+    .cache_op      = hvmemul_cache_op_discard,
      .cpuid         = x86emul_cpuid,
      .get_fpu       = hvmemul_get_fpu,
      .put_fpu       = hvmemul_put_fpu,
--- a/xen/arch/x86/pv/emul-priv-op.c
+++ b/xen/arch/x86/pv/emul-priv-op.c
@@ -1118,9 +1118,11 @@ static int write_msr(unsigned int reg, u
      return X86EMUL_UNHANDLEABLE;
  }
  
-/* Name it differently to avoid clashing with wbinvd() */
-static int _wbinvd(struct x86_emulate_ctxt *ctxt)
+static int cache_op(enum x86emul_cache_op op, enum x86_segment seg,
+                    unsigned long offset, struct x86_emulate_ctxt *ctxt)
  {
+    ASSERT(op == x86emul_wbinvd);
+
      /* Ignore the instruction if unprivileged. */
      if ( !cache_flush_permitted(current->domain) )
          /*
@@ -1238,7 +1240,7 @@ static const struct x86_emulate_ops priv
      .read_msr            = read_msr,
      .write_msr           = write_msr,
      .cpuid               = x86emul_cpuid,
-    .wbinvd              = _wbinvd,
+    .cache_op            = cache_op,
  };
  
  int pv_emulate_privileged_op(struct cpu_user_regs *regs)
--- a/xen/arch/x86/x86_emulate/x86_emulate.c
+++ b/xen/arch/x86/x86_emulate/x86_emulate.c
@@ -5933,8 +5933,11 @@ x86_emulate(
      case X86EMUL_OPC(0x0f, 0x08): /* invd */
      case X86EMUL_OPC(0x0f, 0x09): /* wbinvd */
          generate_exception_if(!mode_ring0(), EXC_GP, 0);
-        fail_if(ops->wbinvd == NULL);
-        if ( (rc = ops->wbinvd(ctxt)) != 0 )
+        fail_if(!ops->cache_op);
+        if ( (rc = ops->cache_op(b == 0x09 ? x86emul_wbinvd
+                                           : x86emul_invd,
+                                 x86_seg_none, 0,
+                                 ctxt)) != X86EMUL_OKAY )
              goto done;
          break;
  
@@ -7801,8 +7804,9 @@ x86_emulate(
              /* else clwb */
              fail_if(!vex.pfx);
              vcpu_must_have(clwb);
-            fail_if(!ops->wbinvd);
-            if ( (rc = ops->wbinvd(ctxt)) != X86EMUL_OKAY )
+            fail_if(!ops->cache_op);
+            if ( (rc = ops->cache_op(x86emul_clwb, ea.mem.seg, ea.mem.off,
+                                     ctxt)) != X86EMUL_OKAY )
                  goto done;
              break;
          case 7:
@@ -7818,8 +7822,11 @@ x86_emulate(
                  vcpu_must_have(clflush);
              else
                  vcpu_must_have(clflushopt);
-            fail_if(ops->wbinvd == NULL);
-            if ( (rc = ops->wbinvd(ctxt)) != 0 )
+            fail_if(!ops->cache_op);
+            if ( (rc = ops->cache_op(vex.pfx ? x86emul_clflushopt
+                                             : x86emul_clflush,
+                                     ea.mem.seg, ea.mem.off,
+                                     ctxt)) != X86EMUL_OKAY )
                  goto done;
              break;
          default:
--- a/xen/arch/x86/x86_emulate/x86_emulate.h
+++ b/xen/arch/x86/x86_emulate/x86_emulate.h
@@ -176,6 +176,14 @@ enum x86_emulate_fpu_type {
      X86EMUL_FPU_none
  };
  
+enum x86emul_cache_op {
+    x86emul_clflush,
+    x86emul_clflushopt,
+    x86emul_clwb,
+    x86emul_invd,
+    x86emul_wbinvd,
+};
+
  struct x86_emulate_state;
  
  /*
@@ -452,8 +460,15 @@ struct x86_emulate_ops
          uint64_t val,
          struct x86_emulate_ctxt *ctxt);
  
-    /* wbinvd: Write-back and invalidate cache contents. */
-    int (*wbinvd)(
+    /*
+     * cache_op: Write-back and/or invalidate cache contents.
+     *
+     * @seg:@offset applicable only to some of enum x86emul_cache_op.
+     */
+    int (*cache_op)(
+        enum x86emul_cache_op op,
+        enum x86_segment seg,
+        unsigned long offset,
          struct x86_emulate_ctxt *ctxt);
  
      /* cpuid: Emulate CPUID via given set of EAX-EDX inputs/outputs. */
--- a/xen/include/asm-x86/cpufeature.h
+++ b/xen/include/asm-x86/cpufeature.h
@@ -102,6 +102,8 @@
  #define cpu_has_rdseed          boot_cpu_has(X86_FEATURE_RDSEED)
  #define cpu_has_smap            boot_cpu_has(X86_FEATURE_SMAP)
  #define cpu_has_avx512_ifma     boot_cpu_has(X86_FEATURE_AVX512_IFMA)
+#define cpu_has_clflushopt      boot_cpu_has(X86_FEATURE_CLFLUSHOPT)
+#define cpu_has_clwb            boot_cpu_has(X86_FEATURE_CLWB)
  #define cpu_has_avx512er        boot_cpu_has(X86_FEATURE_AVX512ER)
  #define cpu_has_avx512cd        boot_cpu_has(X86_FEATURE_AVX512CD)
  #define cpu_has_sha             boot_cpu_has(X86_FEATURE_SHA)
--- a/xen/include/asm-x86/system.h
+++ b/xen/include/asm-x86/system.h
@@ -21,6 +21,23 @@ static inline void clflush(const void *p
      asm volatile ( "clflush %0" :: "m" (*(const char *)p) );
  }
  
+static inline void clflushopt(const void *p)
+{
+    asm volatile ( "data16 clflush %0" :: "m" (*(const char *)p) );
+}
+
+static inline void clwb(const void *p)
+{
+#if defined(HAVE_AS_CLWB)
+    asm volatile ( "clwb %0" :: "m" (*(const char *)p) );
+#elif defined(HAVE_AS_XSAVEOPT)
+    asm volatile ( "data16 xsaveopt %0" :: "m" (*(const char *)p) );
+#else
+    asm volatile ( ".byte 0x66, 0x0f, 0xae, 0x32"
+                   :: "d" (p), "m" (*(const char *)p) );
+#endif
+}
+
  #define xchg(ptr,v) \
      ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr))))
  

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Re: [Xen-devel] [PATCH 1/6] x86emul: generalize wbinvd() hook

Posted by Paul Durrant 2 weeks ago
> -----Original Message-----
> From: Jan Beulich <JBeulich@suse.com>
> Sent: 01 July 2019 12:56
> To: xen-devel@lists.xenproject.org
> Cc: Andrew Cooper <Andrew.Cooper3@citrix.com>; Paul Durrant <Paul.Durrant@citrix.com>; Roger Pau Monne
> <roger.pau@citrix.com>; Wei Liu <wl@xen.org>
> Subject: [PATCH 1/6] x86emul: generalize wbinvd() hook
> 
> The hook is already in use for other purposes, and emulating e.g.
> CLFLUSH by issuing WBINVD is, well, not very nice. Rename the hook and
> add parameters. Use lighter weight flushing insns when possible in
> hvmemul_cache_op().
> 
> hvmemul_cache_op() treating x86emul_invd the same as x86emul_wbinvd is
> to retain original behavior, but I'm not sure this is what we want in
> the long run.
> 
> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> ---
> v2: Use cache_op() as hook name. Convert macros to inline functions in
>      system.h. Re-base.
> ---
> I was unsure about PREFETCH* and CLDEMOTE - both are cache management
> insns too, but the emulator currently treats them as a NOP without
> invoking any hooks.
> I was also uncertain about the new cache_flush_permitted() instance -
> generally I think it wouldn't be too bad if we allowed line flushes in
> all cases, in which case the checks in the ->wbinvd_intercept() handlers
> would suffice (as they did until now).
>
[snip]
> --- a/xen/arch/x86/hvm/emulate.c
> +++ b/xen/arch/x86/hvm/emulate.c
> @@ -25,6 +25,7 @@
>   #include <asm/hvm/trace.h>
>   #include <asm/hvm/support.h>
>   #include <asm/hvm/svm/svm.h>
> +#include <asm/iocap.h>
>   #include <asm/vm_event.h>
> 
>   static void hvmtrace_io_assist(const ioreq_t *p)
> @@ -555,16 +556,12 @@ static void *hvmemul_map_linear_addr(
>       mfn_t *mfn = &hvmemul_ctxt->mfn[0];
> 
>       /*
> -     * The caller has no legitimate reason for trying a zero-byte write, but
> -     * all other code here is written to work if the check below was dropped.
> -     *
> -     * The maximum write size depends on the number of adjacent mfns[] which
> +     * The maximum access size depends on the number of adjacent mfns[] which
>        * can be vmap()'d, accouting for possible misalignment within the region.
>        * The higher level emulation callers are responsible for ensuring that
> -     * mfns[] is large enough for the requested write size.
> +     * mfns[] is large enough for the requested access size.
>        */
> -    if ( bytes == 0 ||
> -         nr_frames > ARRAY_SIZE(hvmemul_ctxt->mfn) )
> +    if ( nr_frames > ARRAY_SIZE(hvmemul_ctxt->mfn) )
>       {
>           ASSERT_UNREACHABLE();
>           goto unhandleable;
> @@ -669,8 +666,6 @@ static void hvmemul_unmap_linear_addr(
>       unsigned int i;
>       mfn_t *mfn = &hvmemul_ctxt->mfn[0];
> 
> -    ASSERT(bytes > 0);
> -
>       if ( nr_frames == 1 )
>           unmap_domain_page(mapping);
>       else
> @@ -1473,7 +1468,10 @@ static int hvmemul_write_msr_discard(
>       return X86EMUL_OKAY;
>   }
> 
> -static int hvmemul_wbinvd_discard(
> +static int hvmemul_cache_op_discard(
> +    enum x86emul_cache_op op,
> +    enum x86_segment seg,
> +    unsigned long offset,
>       struct x86_emulate_ctxt *ctxt)
>   {
>       return X86EMUL_OKAY;
> @@ -2149,10 +2147,65 @@ static int hvmemul_write_msr(
>       return rc;
>   }
> 
> -static int hvmemul_wbinvd(
> +static int hvmemul_cache_op(
> +    enum x86emul_cache_op op,
> +    enum x86_segment seg,
> +    unsigned long offset,
>       struct x86_emulate_ctxt *ctxt)
>   {
> -    alternative_vcall(hvm_funcs.wbinvd_intercept);
> +    struct hvm_emulate_ctxt *hvmemul_ctxt =
> +        container_of(ctxt, struct hvm_emulate_ctxt, ctxt);
> +    unsigned long addr, reps = 1;
> +    uint32_t pfec = PFEC_page_present;
> +    int rc;
> +    void *mapping;
> +
> +    if ( !cache_flush_permitted(current->domain) )
> +        return X86EMUL_OKAY;
> +
> +    switch ( op )
> +    {
> +    case x86emul_clflush:
> +    case x86emul_clflushopt:
> +    case x86emul_clwb:
> +        ASSERT(!is_x86_system_segment(seg));
> +
> +        rc = hvmemul_virtual_to_linear(seg, offset, 0, &reps,
> +                                       hvm_access_read, hvmemul_ctxt, &addr);
> +        if ( rc != X86EMUL_OKAY )
> +            break;
> +
> +        if ( hvmemul_ctxt->seg_reg[x86_seg_ss].dpl == 3 )
> +            pfec |= PFEC_user_mode;
> +
> +        mapping = hvmemul_map_linear_addr(addr, 0, pfec, hvmemul_ctxt,
> +                                          current->arch.hvm.data_cache);
> +        if ( mapping == ERR_PTR(~X86EMUL_EXCEPTION) )
> +            return X86EMUL_EXCEPTION;
> +        if ( IS_ERR_OR_NULL(mapping) )
> +            break;
> +
> +        if ( cpu_has_clflush )
> +        {
> +            if ( op == x86emul_clwb && cpu_has_clwb )
> +                clwb(mapping);
> +            else if ( op == x86emul_clflushopt && cpu_has_clflushopt )
> +                clflushopt(mapping);
> +            else
> +                clflush(mapping);
> +
> +            hvmemul_unmap_linear_addr(mapping, addr, 0, hvmemul_ctxt);
> +            break;
> +        }
> +
> +        hvmemul_unmap_linear_addr(mapping, addr, 0, hvmemul_ctxt);

Since the mapping is ditched here, why bother getting one at all in the !cpu_has_clflush case? Are you trying to flush out an error condition that was previously missed?

  Paul
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Re: [Xen-devel] [PATCH 1/6] x86emul: generalize wbinvd() hook

Posted by Jan Beulich 2 weeks ago
On 02.07.2019 12:22, Paul Durrant wrote:
>> From: Jan Beulich <JBeulich@suse.com>
>> Sent: 01 July 2019 12:56
>>
>> @@ -2149,10 +2147,65 @@ static int hvmemul_write_msr(
>>        return rc;
>>    }
>>
>> -static int hvmemul_wbinvd(
>> +static int hvmemul_cache_op(
>> +    enum x86emul_cache_op op,
>> +    enum x86_segment seg,
>> +    unsigned long offset,
>>        struct x86_emulate_ctxt *ctxt)
>>    {
>> -    alternative_vcall(hvm_funcs.wbinvd_intercept);
>> +    struct hvm_emulate_ctxt *hvmemul_ctxt =
>> +        container_of(ctxt, struct hvm_emulate_ctxt, ctxt);
>> +    unsigned long addr, reps = 1;
>> +    uint32_t pfec = PFEC_page_present;
>> +    int rc;
>> +    void *mapping;
>> +
>> +    if ( !cache_flush_permitted(current->domain) )
>> +        return X86EMUL_OKAY;
>> +
>> +    switch ( op )
>> +    {
>> +    case x86emul_clflush:
>> +    case x86emul_clflushopt:
>> +    case x86emul_clwb:
>> +        ASSERT(!is_x86_system_segment(seg));
>> +
>> +        rc = hvmemul_virtual_to_linear(seg, offset, 0, &reps,
>> +                                       hvm_access_read, hvmemul_ctxt, &addr);
>> +        if ( rc != X86EMUL_OKAY )
>> +            break;
>> +
>> +        if ( hvmemul_ctxt->seg_reg[x86_seg_ss].dpl == 3 )
>> +            pfec |= PFEC_user_mode;
>> +
>> +        mapping = hvmemul_map_linear_addr(addr, 0, pfec, hvmemul_ctxt,
>> +                                          current->arch.hvm.data_cache);
>> +        if ( mapping == ERR_PTR(~X86EMUL_EXCEPTION) )
>> +            return X86EMUL_EXCEPTION;

This return ...

>> +        if ( IS_ERR_OR_NULL(mapping) )
>> +            break;
>> +
>> +        if ( cpu_has_clflush )
>> +        {
>> +            if ( op == x86emul_clwb && cpu_has_clwb )
>> +                clwb(mapping);
>> +            else if ( op == x86emul_clflushopt && cpu_has_clflushopt )
>> +                clflushopt(mapping);
>> +            else
>> +                clflush(mapping);
>> +
>> +            hvmemul_unmap_linear_addr(mapping, addr, 0, hvmemul_ctxt);
>> +            break;
>> +        }
>> +
>> +        hvmemul_unmap_linear_addr(mapping, addr, 0, hvmemul_ctxt);
> 
> Since the mapping is ditched here, why bother getting one at all in the
> !cpu_has_clflush case? Are you trying to flush out an error condition> that was previously missed?

... is what I'm after: We want exception behavior to be correct.

Jan
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Re: [Xen-devel] [PATCH 1/6] x86emul: generalize wbinvd() hook

Posted by Paul Durrant 2 weeks ago
> -----Original Message-----
> From: Jan Beulich <JBeulich@suse.com>
> Sent: 02 July 2019 11:50
> To: Paul Durrant <Paul.Durrant@citrix.com>; xen-devel@lists.xenproject.org
> Cc: Andrew Cooper <Andrew.Cooper3@citrix.com>; Roger Pau Monne <roger.pau@citrix.com>; Wei Liu
> <wl@xen.org>
> Subject: Re: [PATCH 1/6] x86emul: generalize wbinvd() hook
> 
> On 02.07.2019 12:22, Paul Durrant wrote:
> >> From: Jan Beulich <JBeulich@suse.com>
> >> Sent: 01 July 2019 12:56
> >>
> >> @@ -2149,10 +2147,65 @@ static int hvmemul_write_msr(
> >>        return rc;
> >>    }
> >>
> >> -static int hvmemul_wbinvd(
> >> +static int hvmemul_cache_op(
> >> +    enum x86emul_cache_op op,
> >> +    enum x86_segment seg,
> >> +    unsigned long offset,
> >>        struct x86_emulate_ctxt *ctxt)
> >>    {
> >> -    alternative_vcall(hvm_funcs.wbinvd_intercept);
> >> +    struct hvm_emulate_ctxt *hvmemul_ctxt =
> >> +        container_of(ctxt, struct hvm_emulate_ctxt, ctxt);
> >> +    unsigned long addr, reps = 1;
> >> +    uint32_t pfec = PFEC_page_present;
> >> +    int rc;
> >> +    void *mapping;
> >> +
> >> +    if ( !cache_flush_permitted(current->domain) )
> >> +        return X86EMUL_OKAY;
> >> +
> >> +    switch ( op )
> >> +    {
> >> +    case x86emul_clflush:
> >> +    case x86emul_clflushopt:
> >> +    case x86emul_clwb:
> >> +        ASSERT(!is_x86_system_segment(seg));
> >> +
> >> +        rc = hvmemul_virtual_to_linear(seg, offset, 0, &reps,
> >> +                                       hvm_access_read, hvmemul_ctxt, &addr);
> >> +        if ( rc != X86EMUL_OKAY )
> >> +            break;
> >> +
> >> +        if ( hvmemul_ctxt->seg_reg[x86_seg_ss].dpl == 3 )
> >> +            pfec |= PFEC_user_mode;
> >> +
> >> +        mapping = hvmemul_map_linear_addr(addr, 0, pfec, hvmemul_ctxt,
> >> +                                          current->arch.hvm.data_cache);
> >> +        if ( mapping == ERR_PTR(~X86EMUL_EXCEPTION) )
> >> +            return X86EMUL_EXCEPTION;
> 
> This return ...
> 
> >> +        if ( IS_ERR_OR_NULL(mapping) )
> >> +            break;
> >> +
> >> +        if ( cpu_has_clflush )
> >> +        {
> >> +            if ( op == x86emul_clwb && cpu_has_clwb )
> >> +                clwb(mapping);
> >> +            else if ( op == x86emul_clflushopt && cpu_has_clflushopt )
> >> +                clflushopt(mapping);
> >> +            else
> >> +                clflush(mapping);
> >> +
> >> +            hvmemul_unmap_linear_addr(mapping, addr, 0, hvmemul_ctxt);
> >> +            break;
> >> +        }
> >> +
> >> +        hvmemul_unmap_linear_addr(mapping, addr, 0, hvmemul_ctxt);
> >
> > Since the mapping is ditched here, why bother getting one at all in the
> > !cpu_has_clflush case? Are you trying to flush out an error condition> that was previously missed?
> 
> ... is what I'm after: We want exception behavior to be correct.
> 

Ok, fair enough. Just wasn't obvious to me from the commit comment.

  Paul
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[Xen-devel] [PATCH 2/6] x86emul: support WBNOINVD

Posted by Jan Beulich 2 weeks ago
Rev 035 of Intel's ISA extensions document does not state intercept
behavior for the insn (I've been in-officially told that the distinction
is going to be by exit qualification, as I would have assumed
considering that this way it's sufficiently transparent to unaware
software, and using WBINVD in place of WBNOINVD is always correct, just
less efficient), so in the HVM case for now it'll be backed by the same
->wbinvd_intercept() handlers.

Use this occasion and also add the two missing table entries for
CLDEMOTE, which doesn't require any further changes to make work.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
v2: Re-base. Convert wbnoinvd() inline function.

--- a/tools/libxl/libxl_cpuid.c
+++ b/tools/libxl/libxl_cpuid.c
@@ -208,6 +208,7 @@ int libxl_cpuid_parse_config(libxl_cpuid
          {"avx512-bitalg",0x00000007,  0, CPUID_REG_ECX, 12,  1},
          {"avx512-vpopcntdq",0x00000007,0,CPUID_REG_ECX, 14,  1},
          {"rdpid",        0x00000007,  0, CPUID_REG_ECX, 22,  1},
+        {"cldemote",     0x00000007,  0, CPUID_REG_ECX, 25,  1},
  
          {"avx512-4vnniw",0x00000007,  0, CPUID_REG_EDX,  2,  1},
          {"avx512-4fmaps",0x00000007,  0, CPUID_REG_EDX,  3,  1},
@@ -256,6 +257,7 @@ int libxl_cpuid_parse_config(libxl_cpuid
  
          {"invtsc",       0x80000007, NA, CPUID_REG_EDX,  8,  1},
  
+        {"wbnoinvd",     0x80000008, NA, CPUID_REG_EBX,  9,  1},
          {"ibpb",         0x80000008, NA, CPUID_REG_EBX, 12,  1},
          {"nc",           0x80000008, NA, CPUID_REG_ECX,  0,  8},
          {"apicidsize",   0x80000008, NA, CPUID_REG_ECX, 12,  4},
--- a/tools/misc/xen-cpuid.c
+++ b/tools/misc/xen-cpuid.c
@@ -146,6 +146,8 @@ static const char *const str_e8b[32] =
  {
      [ 0] = "clzero",
  
+    /* [ 8] */            [ 9] = "wbnoinvd",
+
      [12] = "ibpb",
  };
  
--- a/xen/arch/x86/hvm/emulate.c
+++ b/xen/arch/x86/hvm/emulate.c
@@ -2202,6 +2202,7 @@ static int hvmemul_cache_op(
          /* fall through */
      case x86emul_invd:
      case x86emul_wbinvd:
+    case x86emul_wbnoinvd:
          alternative_vcall(hvm_funcs.wbinvd_intercept);
          break;
      }
--- a/xen/arch/x86/pv/emul-priv-op.c
+++ b/xen/arch/x86/pv/emul-priv-op.c
@@ -1121,7 +1121,7 @@ static int write_msr(unsigned int reg, u
  static int cache_op(enum x86emul_cache_op op, enum x86_segment seg,
                      unsigned long offset, struct x86_emulate_ctxt *ctxt)
  {
-    ASSERT(op == x86emul_wbinvd);
+    ASSERT(op == x86emul_wbinvd || op == x86emul_wbnoinvd);
  
      /* Ignore the instruction if unprivileged. */
      if ( !cache_flush_permitted(current->domain) )
@@ -1130,6 +1130,8 @@ static int cache_op(enum x86emul_cache_o
           * newer linux uses this in some start-of-day timing loops.
           */
          ;
+    else if ( op == x86emul_wbnoinvd && cpu_has_wbnoinvd )
+        wbnoinvd();
      else
          wbinvd();
  
--- a/xen/arch/x86/x86_emulate/x86_emulate.c
+++ b/xen/arch/x86/x86_emulate/x86_emulate.c
@@ -1869,6 +1869,7 @@ in_protmode(
  #define vcpu_has_fma4()        (ctxt->cpuid->extd.fma4)
  #define vcpu_has_tbm()         (ctxt->cpuid->extd.tbm)
  #define vcpu_has_clzero()      (ctxt->cpuid->extd.clzero)
+#define vcpu_has_wbnoinvd()    (ctxt->cpuid->extd.wbnoinvd)
  
  #define vcpu_has_bmi1()        (ctxt->cpuid->feat.bmi1)
  #define vcpu_has_hle()         (ctxt->cpuid->feat.hle)
@@ -5931,10 +5932,13 @@ x86_emulate(
          break;
  
      case X86EMUL_OPC(0x0f, 0x08): /* invd */
-    case X86EMUL_OPC(0x0f, 0x09): /* wbinvd */
+    case X86EMUL_OPC(0x0f, 0x09): /* wbinvd / wbnoinvd */
          generate_exception_if(!mode_ring0(), EXC_GP, 0);
          fail_if(!ops->cache_op);
-        if ( (rc = ops->cache_op(b == 0x09 ? x86emul_wbinvd
+        if ( (rc = ops->cache_op(b == 0x09 ? !repe_prefix() ||
+                                             !vcpu_has_wbnoinvd()
+                                             ? x86emul_wbinvd
+                                             : x86emul_wbnoinvd
                                             : x86emul_invd,
                                   x86_seg_none, 0,
                                   ctxt)) != X86EMUL_OKAY )
--- a/xen/arch/x86/x86_emulate/x86_emulate.h
+++ b/xen/arch/x86/x86_emulate/x86_emulate.h
@@ -182,6 +182,7 @@ enum x86emul_cache_op {
      x86emul_clwb,
      x86emul_invd,
      x86emul_wbinvd,
+    x86emul_wbnoinvd,
  };
  
  struct x86_emulate_state;
--- a/xen/include/asm-x86/cpufeature.h
+++ b/xen/include/asm-x86/cpufeature.h
@@ -129,6 +129,9 @@
  #define cpu_has_avx512_4fmaps   boot_cpu_has(X86_FEATURE_AVX512_4FMAPS)
  #define cpu_has_tsx_force_abort boot_cpu_has(X86_FEATURE_TSX_FORCE_ABORT)
  
+/* CPUID level 0x80000008.ebx */
+#define cpu_has_wbnoinvd        boot_cpu_has(X86_FEATURE_WBNOINVD)
+
  /* Synthesized. */
  #define cpu_has_arch_perfmon    boot_cpu_has(X86_FEATURE_ARCH_PERFMON)
  #define cpu_has_cpuid_faulting  boot_cpu_has(X86_FEATURE_CPUID_FAULTING)
--- a/xen/include/asm-x86/system.h
+++ b/xen/include/asm-x86/system.h
@@ -16,6 +16,11 @@ static inline void wbinvd(void)
      asm volatile ( "wbinvd" ::: "memory" );
  }
  
+static inline void wbnoinvd(void)
+{
+    asm volatile ( "repe; wbinvd" : : : "memory" );
+}
+
  static inline void clflush(const void *p)
  {
      asm volatile ( "clflush %0" :: "m" (*(const char *)p) );
--- a/xen/include/public/arch-x86/cpufeatureset.h
+++ b/xen/include/public/arch-x86/cpufeatureset.h
@@ -236,6 +236,7 @@ XEN_CPUFEATURE(AVX512_VNNI,   6*32+11) /
  XEN_CPUFEATURE(AVX512_BITALG, 6*32+12) /*A  Support for VPOPCNT[B,W] and VPSHUFBITQMB */
  XEN_CPUFEATURE(AVX512_VPOPCNTDQ, 6*32+14) /*A  POPCNT for vectors of DW/QW */
  XEN_CPUFEATURE(RDPID,         6*32+22) /*A  RDPID instruction */
+XEN_CPUFEATURE(CLDEMOTE,      6*32+25) /*A  CLDEMOTE instruction */
  
  /* AMD-defined CPU features, CPUID level 0x80000007.edx, word 7 */
  XEN_CPUFEATURE(ITSC,          7*32+ 8) /*   Invariant TSC */
@@ -243,6 +244,7 @@ XEN_CPUFEATURE(EFRO,          7*32+10) /
  
  /* AMD-defined CPU features, CPUID level 0x80000008.ebx, word 8 */
  XEN_CPUFEATURE(CLZERO,        8*32+ 0) /*A  CLZERO instruction */
+XEN_CPUFEATURE(WBNOINVD,      8*32+ 9) /*A  WBNOINVD instruction */
  XEN_CPUFEATURE(IBPB,          8*32+12) /*A  IBPB support only (no IBRS, used by AMD) */
  
  /* Intel-defined CPU features, CPUID level 0x00000007:0.edx, word 9 */

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Re: [Xen-devel] [PATCH 2/6] x86emul: support WBNOINVD

Posted by Paul Durrant 2 weeks ago
> -----Original Message-----
> From: Jan Beulich <JBeulich@suse.com>
> Sent: 01 July 2019 12:57
> To: xen-devel@lists.xenproject.org
> Cc: Andrew Cooper <Andrew.Cooper3@citrix.com>; Paul Durrant <Paul.Durrant@citrix.com>; Roger Pau Monne
> <roger.pau@citrix.com>; Wei Liu <wl@xen.org>
> Subject: [PATCH 2/6] x86emul: support WBNOINVD
> 
> Rev 035 of Intel's ISA extensions document does not state intercept
> behavior for the insn (I've been in-officially told that the distinction
> is going to be by exit qualification, as I would have assumed
> considering that this way it's sufficiently transparent to unaware
> software, and using WBINVD in place of WBNOINVD is always correct, just
> less efficient), so in the HVM case for now it'll be backed by the same
> ->wbinvd_intercept() handlers.
> 
> Use this occasion and also add the two missing table entries for
> CLDEMOTE, which doesn't require any further changes to make work.
> 
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Reviewed-by: Paul Durrant <paul.durrant@citrix.com>

> ---
> v2: Re-base. Convert wbnoinvd() inline function.
> 
> --- a/tools/libxl/libxl_cpuid.c
> +++ b/tools/libxl/libxl_cpuid.c
> @@ -208,6 +208,7 @@ int libxl_cpuid_parse_config(libxl_cpuid
>           {"avx512-bitalg",0x00000007,  0, CPUID_REG_ECX, 12,  1},
>           {"avx512-vpopcntdq",0x00000007,0,CPUID_REG_ECX, 14,  1},
>           {"rdpid",        0x00000007,  0, CPUID_REG_ECX, 22,  1},
> +        {"cldemote",     0x00000007,  0, CPUID_REG_ECX, 25,  1},
> 
>           {"avx512-4vnniw",0x00000007,  0, CPUID_REG_EDX,  2,  1},
>           {"avx512-4fmaps",0x00000007,  0, CPUID_REG_EDX,  3,  1},
> @@ -256,6 +257,7 @@ int libxl_cpuid_parse_config(libxl_cpuid
> 
>           {"invtsc",       0x80000007, NA, CPUID_REG_EDX,  8,  1},
> 
> +        {"wbnoinvd",     0x80000008, NA, CPUID_REG_EBX,  9,  1},
>           {"ibpb",         0x80000008, NA, CPUID_REG_EBX, 12,  1},
>           {"nc",           0x80000008, NA, CPUID_REG_ECX,  0,  8},
>           {"apicidsize",   0x80000008, NA, CPUID_REG_ECX, 12,  4},
> --- a/tools/misc/xen-cpuid.c
> +++ b/tools/misc/xen-cpuid.c
> @@ -146,6 +146,8 @@ static const char *const str_e8b[32] =
>   {
>       [ 0] = "clzero",
> 
> +    /* [ 8] */            [ 9] = "wbnoinvd",
> +
>       [12] = "ibpb",
>   };
> 
> --- a/xen/arch/x86/hvm/emulate.c
> +++ b/xen/arch/x86/hvm/emulate.c
> @@ -2202,6 +2202,7 @@ static int hvmemul_cache_op(
>           /* fall through */
>       case x86emul_invd:
>       case x86emul_wbinvd:
> +    case x86emul_wbnoinvd:
>           alternative_vcall(hvm_funcs.wbinvd_intercept);
>           break;
>       }
> --- a/xen/arch/x86/pv/emul-priv-op.c
> +++ b/xen/arch/x86/pv/emul-priv-op.c
> @@ -1121,7 +1121,7 @@ static int write_msr(unsigned int reg, u
>   static int cache_op(enum x86emul_cache_op op, enum x86_segment seg,
>                       unsigned long offset, struct x86_emulate_ctxt *ctxt)
>   {
> -    ASSERT(op == x86emul_wbinvd);
> +    ASSERT(op == x86emul_wbinvd || op == x86emul_wbnoinvd);
> 
>       /* Ignore the instruction if unprivileged. */
>       if ( !cache_flush_permitted(current->domain) )
> @@ -1130,6 +1130,8 @@ static int cache_op(enum x86emul_cache_o
>            * newer linux uses this in some start-of-day timing loops.
>            */
>           ;
> +    else if ( op == x86emul_wbnoinvd && cpu_has_wbnoinvd )
> +        wbnoinvd();
>       else
>           wbinvd();
> 
> --- a/xen/arch/x86/x86_emulate/x86_emulate.c
> +++ b/xen/arch/x86/x86_emulate/x86_emulate.c
> @@ -1869,6 +1869,7 @@ in_protmode(
>   #define vcpu_has_fma4()        (ctxt->cpuid->extd.fma4)
>   #define vcpu_has_tbm()         (ctxt->cpuid->extd.tbm)
>   #define vcpu_has_clzero()      (ctxt->cpuid->extd.clzero)
> +#define vcpu_has_wbnoinvd()    (ctxt->cpuid->extd.wbnoinvd)
> 
>   #define vcpu_has_bmi1()        (ctxt->cpuid->feat.bmi1)
>   #define vcpu_has_hle()         (ctxt->cpuid->feat.hle)
> @@ -5931,10 +5932,13 @@ x86_emulate(
>           break;
> 
>       case X86EMUL_OPC(0x0f, 0x08): /* invd */
> -    case X86EMUL_OPC(0x0f, 0x09): /* wbinvd */
> +    case X86EMUL_OPC(0x0f, 0x09): /* wbinvd / wbnoinvd */
>           generate_exception_if(!mode_ring0(), EXC_GP, 0);
>           fail_if(!ops->cache_op);
> -        if ( (rc = ops->cache_op(b == 0x09 ? x86emul_wbinvd
> +        if ( (rc = ops->cache_op(b == 0x09 ? !repe_prefix() ||
> +                                             !vcpu_has_wbnoinvd()
> +                                             ? x86emul_wbinvd
> +                                             : x86emul_wbnoinvd
>                                              : x86emul_invd,
>                                    x86_seg_none, 0,
>                                    ctxt)) != X86EMUL_OKAY )
> --- a/xen/arch/x86/x86_emulate/x86_emulate.h
> +++ b/xen/arch/x86/x86_emulate/x86_emulate.h
> @@ -182,6 +182,7 @@ enum x86emul_cache_op {
>       x86emul_clwb,
>       x86emul_invd,
>       x86emul_wbinvd,
> +    x86emul_wbnoinvd,
>   };
> 
>   struct x86_emulate_state;
> --- a/xen/include/asm-x86/cpufeature.h
> +++ b/xen/include/asm-x86/cpufeature.h
> @@ -129,6 +129,9 @@
>   #define cpu_has_avx512_4fmaps   boot_cpu_has(X86_FEATURE_AVX512_4FMAPS)
>   #define cpu_has_tsx_force_abort boot_cpu_has(X86_FEATURE_TSX_FORCE_ABORT)
> 
> +/* CPUID level 0x80000008.ebx */
> +#define cpu_has_wbnoinvd        boot_cpu_has(X86_FEATURE_WBNOINVD)
> +
>   /* Synthesized. */
>   #define cpu_has_arch_perfmon    boot_cpu_has(X86_FEATURE_ARCH_PERFMON)
>   #define cpu_has_cpuid_faulting  boot_cpu_has(X86_FEATURE_CPUID_FAULTING)
> --- a/xen/include/asm-x86/system.h
> +++ b/xen/include/asm-x86/system.h
> @@ -16,6 +16,11 @@ static inline void wbinvd(void)
>       asm volatile ( "wbinvd" ::: "memory" );
>   }
> 
> +static inline void wbnoinvd(void)
> +{
> +    asm volatile ( "repe; wbinvd" : : : "memory" );
> +}
> +
>   static inline void clflush(const void *p)
>   {
>       asm volatile ( "clflush %0" :: "m" (*(const char *)p) );
> --- a/xen/include/public/arch-x86/cpufeatureset.h
> +++ b/xen/include/public/arch-x86/cpufeatureset.h
> @@ -236,6 +236,7 @@ XEN_CPUFEATURE(AVX512_VNNI,   6*32+11) /
>   XEN_CPUFEATURE(AVX512_BITALG, 6*32+12) /*A  Support for VPOPCNT[B,W] and VPSHUFBITQMB */
>   XEN_CPUFEATURE(AVX512_VPOPCNTDQ, 6*32+14) /*A  POPCNT for vectors of DW/QW */
>   XEN_CPUFEATURE(RDPID,         6*32+22) /*A  RDPID instruction */
> +XEN_CPUFEATURE(CLDEMOTE,      6*32+25) /*A  CLDEMOTE instruction */
> 
>   /* AMD-defined CPU features, CPUID level 0x80000007.edx, word 7 */
>   XEN_CPUFEATURE(ITSC,          7*32+ 8) /*   Invariant TSC */
> @@ -243,6 +244,7 @@ XEN_CPUFEATURE(EFRO,          7*32+10) /
> 
>   /* AMD-defined CPU features, CPUID level 0x80000008.ebx, word 8 */
>   XEN_CPUFEATURE(CLZERO,        8*32+ 0) /*A  CLZERO instruction */
> +XEN_CPUFEATURE(WBNOINVD,      8*32+ 9) /*A  WBNOINVD instruction */
>   XEN_CPUFEATURE(IBPB,          8*32+12) /*A  IBPB support only (no IBRS, used by AMD) */
> 
>   /* Intel-defined CPU features, CPUID level 0x00000007:0.edx, word 9 */

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[Xen-devel] [PATCH 3/6] x86emul: generalize invlpg() hook

Posted by Jan Beulich 2 weeks ago
The hook is already in use for INVLPGA as well. Rename the hook and add
parameters. For the moment INVLPGA with a non-zero ASID remains
unsupported, but the TODO item gets pushed into the actual hook handler.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
v2: New.

--- a/tools/fuzz/x86_instruction_emulator/fuzz-emul.c
+++ b/tools/fuzz/x86_instruction_emulator/fuzz-emul.c
@@ -370,16 +370,23 @@ static int fuzz_cmpxchg(
      return maybe_fail(ctxt, "cmpxchg", true);
  }
  
-static int fuzz_invlpg(
-    enum x86_segment seg,
-    unsigned long offset,
+static int fuzz_tlb_op(
+    enum x86emul_tlb_op op,
+    unsigned long addr,
+    unsigned long aux,
      struct x86_emulate_ctxt *ctxt)
  {
-    /* invlpg(), unlike all other hooks, may be called with x86_seg_none. */
-    assert(is_x86_user_segment(seg) || seg == x86_seg_none);
-    assert(ctxt->addr_size == 64 || !(offset >> 32));
+    switch ( op )
+    {
+    case x86emul_invlpg:
+        assert(is_x86_user_segment(aux));
+        /* fall through */
+    case x86emul_invlpga:
+        assert(ctxt->addr_size == 64 || !(addr >> 32));
+        break;
+    }
  
-    return maybe_fail(ctxt, "invlpg", false);
+    return maybe_fail(ctxt, "TLB-management", false);
  }
  
  static int fuzz_cache_op(
@@ -624,7 +631,7 @@ static const struct x86_emulate_ops all_
      SET(read_msr),
      SET(write_msr),
      SET(cache_op),
-    SET(invlpg),
+    SET(tlb_op),
      .get_fpu    = emul_test_get_fpu,
      .put_fpu    = emul_test_put_fpu,
      .cpuid      = emul_test_cpuid,
@@ -733,12 +740,12 @@ enum {
      HOOK_read_msr,
      HOOK_write_msr,
      HOOK_cache_op,
+    HOOK_tlb_op,
      HOOK_cpuid,
      HOOK_inject_hw_exception,
      HOOK_inject_sw_interrupt,
      HOOK_get_fpu,
      HOOK_put_fpu,
-    HOOK_invlpg,
      HOOK_vmfunc,
      CANONICALIZE_rip,
      CANONICALIZE_rsp,
@@ -777,9 +784,9 @@ static void disable_hooks(struct x86_emu
      MAYBE_DISABLE_HOOK(read_msr);
      MAYBE_DISABLE_HOOK(write_msr);
      MAYBE_DISABLE_HOOK(cache_op);
+    MAYBE_DISABLE_HOOK(tlb_op);
      MAYBE_DISABLE_HOOK(cpuid);
      MAYBE_DISABLE_HOOK(get_fpu);
-    MAYBE_DISABLE_HOOK(invlpg);
  }
  
  /*
--- a/xen/arch/x86/hvm/emulate.c
+++ b/xen/arch/x86/hvm/emulate.c
@@ -2339,36 +2339,53 @@ static void hvmemul_put_fpu(
      }
  }
  
-static int hvmemul_invlpg(
-    enum x86_segment seg,
-    unsigned long offset,
+static int hvmemul_tlb_op(
+    enum x86emul_tlb_op op,
+    unsigned long addr,
+    unsigned long aux,
      struct x86_emulate_ctxt *ctxt)
  {
      struct hvm_emulate_ctxt *hvmemul_ctxt =
          container_of(ctxt, struct hvm_emulate_ctxt, ctxt);
-    unsigned long addr, reps = 1;
-    int rc;
-
-    rc = hvmemul_virtual_to_linear(
-        seg, offset, 1, &reps, hvm_access_none, hvmemul_ctxt, &addr);
+    unsigned long reps = 1;
+    int rc = X86EMUL_OKAY;
  
-    if ( rc == X86EMUL_EXCEPTION )
+    switch ( op )
      {
-        /*
-         * `invlpg` takes segment bases into account, but is not subject to
-         * faults from segment type/limit checks, and is specified as a NOP
-         * when issued on non-canonical addresses.
-         *
-         * hvmemul_virtual_to_linear() raises exceptions for type/limit
-         * violations, so squash them.
-         */
-        x86_emul_reset_event(ctxt);
-        rc = X86EMUL_OKAY;
+    case x86emul_invlpg:
+        rc = hvmemul_virtual_to_linear(aux, addr, 1, &reps, hvm_access_none,
+                                       hvmemul_ctxt, &addr);
+
+        if ( rc == X86EMUL_EXCEPTION )
+        {
+            /*
+             * `invlpg` takes segment bases into account, but is not subject
+             * to faults from segment type/limit checks, and is specified as
+             * a NOP when issued on non-canonical addresses.
+             *
+             * hvmemul_virtual_to_linear() raises exceptions for type/limit
+             * violations, so squash them.
+             */
+            x86_emul_reset_event(ctxt);
+            rc = X86EMUL_OKAY;
+        }
+
+        if ( rc == X86EMUL_OKAY )
+            paging_invlpg(current, addr);
+        break;
+
+    case x86emul_invlpga:
+        /* TODO: Support ASIDs. */
+        if ( !aux )
+            paging_invlpg(current, addr);
+        else
+        {
+            x86_emul_hw_exception(TRAP_invalid_op, X86_EVENT_NO_EC, ctxt);
+            rc = X86EMUL_EXCEPTION;
+        }
+        break;
      }
  
-    if ( rc == X86EMUL_OKAY )
-        paging_invlpg(current, addr);
-
      return rc;
  }
  
@@ -2408,10 +2425,10 @@ static const struct x86_emulate_ops hvm_
      .read_msr      = hvmemul_read_msr,
      .write_msr     = hvmemul_write_msr,
      .cache_op      = hvmemul_cache_op,
+    .tlb_op        = hvmemul_tlb_op,
      .cpuid         = x86emul_cpuid,
      .get_fpu       = hvmemul_get_fpu,
      .put_fpu       = hvmemul_put_fpu,
-    .invlpg        = hvmemul_invlpg,
      .vmfunc        = hvmemul_vmfunc,
  };
  
@@ -2435,10 +2452,10 @@ static const struct x86_emulate_ops hvm_
      .read_msr      = hvmemul_read_msr,
      .write_msr     = hvmemul_write_msr_discard,
      .cache_op      = hvmemul_cache_op_discard,
+    .tlb_op        = hvmemul_tlb_op,
      .cpuid         = x86emul_cpuid,
      .get_fpu       = hvmemul_get_fpu,
      .put_fpu       = hvmemul_put_fpu,
-    .invlpg        = hvmemul_invlpg,
      .vmfunc        = hvmemul_vmfunc,
  };
  
--- a/xen/arch/x86/x86_emulate/x86_emulate.c
+++ b/xen/arch/x86/x86_emulate/x86_emulate.c
@@ -5590,10 +5590,9 @@ x86_emulate(
              generate_exception_if(!(msr_val & EFER_SVME) ||
                                    !in_protmode(ctxt, ops), EXC_UD);
              generate_exception_if(!mode_ring0(), EXC_GP, 0);
-            generate_exception_if(_regs.ecx, EXC_UD); /* TODO: Support ASIDs. */
-            fail_if(ops->invlpg == NULL);
-            if ( (rc = ops->invlpg(x86_seg_none, truncate_ea(_regs.r(ax)),
-                                   ctxt)) )
+            fail_if(!ops->tlb_op);
+            if ( (rc = ops->tlb_op(x86emul_invlpga, truncate_ea(_regs.r(ax)),
+                                   _regs.ecx, ctxt)) != X86EMUL_OKAY )
                  goto done;
              break;
  
@@ -5747,8 +5746,9 @@ x86_emulate(
          case GRP7_MEM(7): /* invlpg */
              ASSERT(ea.type == OP_MEM);
              generate_exception_if(!mode_ring0(), EXC_GP, 0);
-            fail_if(ops->invlpg == NULL);
-            if ( (rc = ops->invlpg(ea.mem.seg, ea.mem.off, ctxt)) )
+            fail_if(!ops->tlb_op);
+            if ( (rc = ops->tlb_op(x86emul_invlpg, ea.mem.off, ea.mem.seg,
+                                   ctxt)) != X86EMUL_OKAY )
                  goto done;
              break;
  
--- a/xen/arch/x86/x86_emulate/x86_emulate.h
+++ b/xen/arch/x86/x86_emulate/x86_emulate.h
@@ -185,6 +185,11 @@ enum x86emul_cache_op {
      x86emul_wbnoinvd,
  };
  
+enum x86emul_tlb_op {
+    x86emul_invlpg,
+    x86emul_invlpga,
+};
+
  struct x86_emulate_state;
  
  /*
@@ -472,6 +477,19 @@ struct x86_emulate_ops
          unsigned long offset,
          struct x86_emulate_ctxt *ctxt);
  
+    /*
+     * tlb_op: Invalidate paging structures which map addressed byte.
+     *
+     * @addr and @aux have @op-specific meaning:
+     * - INVLPG:  @aux:@addr represent seg:offset
+     * - INVLPGA: @addr is the linear address, @aux the ASID
+     */
+    int (*tlb_op)(
+        enum x86emul_tlb_op op,
+        unsigned long addr,
+        unsigned long aux,
+        struct x86_emulate_ctxt *ctxt);
+
      /* cpuid: Emulate CPUID via given set of EAX-EDX inputs/outputs. */
      int (*cpuid)(
          uint32_t leaf,
@@ -499,12 +517,6 @@ struct x86_emulate_ops
          enum x86_emulate_fpu_type backout,
          const struct x86_emul_fpu_aux *aux);
  
-    /* invlpg: Invalidate paging structures which map addressed byte. */
-    int (*invlpg)(
-        enum x86_segment seg,
-        unsigned long offset,
-        struct x86_emulate_ctxt *ctxt);
-
      /* vmfunc: Emulate VMFUNC via given set of EAX ECX inputs */
      int (*vmfunc)(
          struct x86_emulate_ctxt *ctxt);

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Re: [Xen-devel] [PATCH 3/6] x86emul: generalize invlpg() hook

Posted by Paul Durrant 2 weeks ago
> -----Original Message-----
> From: Jan Beulich <JBeulich@suse.com>
> Sent: 01 July 2019 12:57
> To: xen-devel@lists.xenproject.org
> Cc: Andrew Cooper <Andrew.Cooper3@citrix.com>; Paul Durrant <Paul.Durrant@citrix.com>; Roger Pau Monne
> <roger.pau@citrix.com>; Wei Liu <wl@xen.org>
> Subject: [PATCH 3/6] x86emul: generalize invlpg() hook
> 
> The hook is already in use for INVLPGA as well. Rename the hook and add
> parameters. For the moment INVLPGA with a non-zero ASID remains
> unsupported, but the TODO item gets pushed into the actual hook handler.
> 
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
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[Xen-devel] [PATCH 4/6] x86: move INVPCID_TYPE_* to x86-defns.h

Posted by Jan Beulich 2 weeks ago
This way the insn emulator can then too use the #define-s.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
v2: New.

--- a/xen/include/asm-x86/invpcid.h
+++ b/xen/include/asm-x86/invpcid.h
@@ -5,11 +5,6 @@
  
  extern bool use_invpcid;
  
-#define INVPCID_TYPE_INDIV_ADDR      0
-#define INVPCID_TYPE_SINGLE_CTXT     1
-#define INVPCID_TYPE_ALL_INCL_GLOBAL 2
-#define INVPCID_TYPE_ALL_NON_GLOBAL  3
-
  #define INVPCID_OPCODE ".byte 0x66, 0x0f, 0x38, 0x82\n"
  #define MODRM_ECX_01   ".byte 0x01\n"
  
@@ -38,25 +33,25 @@ static inline void invpcid(unsigned int
  /* Flush all mappings for a given PCID and addr, not including globals */
  static inline void invpcid_flush_one(unsigned int pcid, unsigned long addr)
  {
-    invpcid(pcid, addr, INVPCID_TYPE_INDIV_ADDR);
+    invpcid(pcid, addr, X86_INVPCID_TYPE_INDIV_ADDR);
  }
  
  /* Flush all mappings for a given PCID, not including globals */
  static inline void invpcid_flush_single_context(unsigned int pcid)
  {
-    invpcid(pcid, 0, INVPCID_TYPE_SINGLE_CTXT);
+    invpcid(pcid, 0, X86_INVPCID_TYPE_SINGLE_CTXT);
  }
  
  /* Flush all mappings, including globals, for all PCIDs */
  static inline void invpcid_flush_all(void)
  {
-    invpcid(0, 0, INVPCID_TYPE_ALL_INCL_GLOBAL);
+    invpcid(0, 0, X86_INVPCID_TYPE_ALL_INCL_GLOBAL);
  }
  
  /* Flush all mappings for all PCIDs, excluding globals */
  static inline void invpcid_flush_all_nonglobals(void)
  {
-    invpcid(0, 0, INVPCID_TYPE_ALL_NON_GLOBAL);
+    invpcid(0, 0, X86_INVPCID_TYPE_ALL_NON_GLOBAL);
  }
  
  #endif	/* _ASM_X86_INVPCID_H_ */
--- a/xen/include/asm-x86/x86-defns.h
+++ b/xen/include/asm-x86/x86-defns.h
@@ -108,4 +108,12 @@
   */
  #define X86_DR7_DEFAULT         0x00000400  /* Default %dr7 value. */
  
+/*
+ * Invalidation types for the INVPCID instruction.
+ */
+#define X86_INVPCID_TYPE_INDIV_ADDR      0
+#define X86_INVPCID_TYPE_SINGLE_CTXT     1
+#define X86_INVPCID_TYPE_ALL_INCL_GLOBAL 2
+#define X86_INVPCID_TYPE_ALL_NON_GLOBAL  3
+
  #endif	/* __XEN_X86_DEFNS_H__ */

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Re: [Xen-devel] [PATCH 4/6] x86: move INVPCID_TYPE_* to x86-defns.h

Posted by Paul Durrant 2 weeks ago
> -----Original Message-----
> From: Jan Beulich <JBeulich@suse.com>
> Sent: 01 July 2019 12:57
> To: xen-devel@lists.xenproject.org
> Cc: Andrew Cooper <Andrew.Cooper3@citrix.com>; Paul Durrant <Paul.Durrant@citrix.com>; Roger Pau Monne
> <roger.pau@citrix.com>; Wei Liu <wl@xen.org>
> Subject: [PATCH 4/6] x86: move INVPCID_TYPE_* to x86-defns.h
> 
> This way the insn emulator can then too use the #define-s.
> 
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
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[Xen-devel] [PATCH 5/6] x86emul: support INVPCID

Posted by Jan Beulich 2 weeks ago
Just like for INVLPGA the HVM hook only supports PCID 0 for the time
being for individual address invalidation. It also translates the other
types to a full flush, which is architecturally permitted and
performance-wise presumably not much worse because emulation is slow
anyway.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
v2: New.

--- a/tools/fuzz/x86_instruction_emulator/fuzz-emul.c
+++ b/tools/fuzz/x86_instruction_emulator/fuzz-emul.c
@@ -382,6 +382,7 @@ static int fuzz_tlb_op(
          assert(is_x86_user_segment(aux));
          /* fall through */
      case x86emul_invlpga:
+    case x86emul_invpcid:
          assert(ctxt->addr_size == 64 || !(addr >> 32));
          break;
      }
--- a/tools/tests/x86_emulator/test_x86_emulator.c
+++ b/tools/tests/x86_emulator/test_x86_emulator.c
@@ -684,6 +684,38 @@ static int read_msr(
      return X86EMUL_UNHANDLEABLE;
  }
  
+#define INVPCID_ADDR 0x12345678
+#define INVPCID_PCID 0x123
+
+static int read_cr_invpcid(
+    unsigned int reg,
+    unsigned long *val,
+    struct x86_emulate_ctxt *ctxt)
+{
+    int rc = emul_test_read_cr(reg, val, ctxt);
+
+    if ( rc == X86EMUL_OKAY && reg == 4 )
+        *val |= X86_CR4_PCIDE;
+
+    return rc;
+}
+
+static int tlb_op_invpcid(
+    enum x86emul_tlb_op op,
+    unsigned long addr,
+    unsigned long aux,
+    struct x86_emulate_ctxt *ctxt)
+{
+    static unsigned int seq;
+
+    if ( op != x86emul_invpcid || addr != INVPCID_ADDR ||
+         x86emul_invpcid_pcid(aux) != (seq < 4 ? 0 : INVPCID_PCID) ||
+         x86emul_invpcid_type(aux) != (seq++ & 3) )
+        return X86EMUL_UNHANDLEABLE;
+
+    return X86EMUL_OKAY;
+}
+
  static struct x86_emulate_ops emulops = {
      .read       = read,
      .insn_fetch = fetch,
@@ -4482,6 +4514,46 @@ int main(int argc, char **argv)
          printf("okay\n");
      }
      else
+        printf("skipped\n");
+
+    printf("%-40s", "Testing invpcid 16(%ecx),%%edx...");
+    if ( stack_exec )
+    {
+        decl_insn(invpcid);
+
+        asm volatile ( put_insn(invpcid, "invpcid 16(%0), %1")
+                       :: "c" (NULL), "d" (0L) );
+
+        res[4] = 0;
+        res[5] = 0;
+        res[6] = INVPCID_ADDR;
+        res[7] = 0;
+        regs.ecx = (unsigned long)res;
+        emulops.tlb_op = tlb_op_invpcid;
+
+        for ( ; ; )
+        {
+            for ( regs.edx = 0; regs.edx < 4; ++regs.edx )
+            {
+                set_insn(invpcid);
+                rc = x86_emulate(&ctxt, &emulops);
+                if ( rc != X86EMUL_OKAY || !check_eip(invpcid) )
+                    goto fail;
+            }
+
+            if ( ctxt.addr_size < 64 || res[4] == INVPCID_PCID )
+                break;
+
+            emulops.read_cr = read_cr_invpcid;
+            res[4] = INVPCID_PCID;
+        }
+
+        emulops.read_cr = emul_test_read_cr;
+        emulops.tlb_op = NULL;
+
+        printf("okay\n");
+    }
+    else
          printf("skipped\n");
  
  #undef decl_insn
--- a/tools/tests/x86_emulator/x86-emulate.c
+++ b/tools/tests/x86_emulator/x86-emulate.c
@@ -72,6 +72,7 @@ bool emul_test_init(void)
       * them.
       */
      cp.basic.movbe = true;
+    cp.feat.invpcid = true;
      cp.feat.adx = true;
      cp.feat.avx512pf = cp.feat.avx512f;
      cp.feat.rdpid = true;
@@ -141,7 +142,7 @@ int emul_test_cpuid(
       */
      if ( leaf == 7 && subleaf == 0 )
      {
-        res->b |= 1U << 19;
+        res->b |= (1U << 10) | (1U << 19);
          if ( res->b & (1U << 16) )
              res->b |= 1U << 26;
          res->c |= 1U << 22;
--- a/xen/arch/x86/hvm/emulate.c
+++ b/xen/arch/x86/hvm/emulate.c
@@ -2374,8 +2374,16 @@ static int hvmemul_tlb_op(
              paging_invlpg(current, addr);
          break;
  
+    case x86emul_invpcid:
+        if ( x86emul_invpcid_type(aux) != X86_INVPCID_TYPE_INDIV_ADDR )
+        {
+            hvm_asid_flush_vcpu(current);
+            break;
+        }
+        aux = x86emul_invpcid_pcid(aux);
+        /* fall through */
      case x86emul_invlpga:
-        /* TODO: Support ASIDs. */
+        /* TODO: Support ASIDs/PCIDs. */
          if ( !aux )
              paging_invlpg(current, addr);
          else
--- a/xen/arch/x86/x86_emulate/x86_emulate.c
+++ b/xen/arch/x86/x86_emulate/x86_emulate.c
@@ -496,6 +496,7 @@ static const struct ext0f38_table {
      [0x7a ... 0x7c] = { .simd_size = simd_none, .two_op = 1 },
      [0x7d ... 0x7e] = { .simd_size = simd_packed_int, .d8s = d8s_vl },
      [0x7f] = { .simd_size = simd_packed_fp, .d8s = d8s_vl },
+    [0x82] = { .simd_size = simd_other },
      [0x83] = { .simd_size = simd_packed_int, .d8s = d8s_vl },
      [0x88] = { .simd_size = simd_packed_fp, .two_op = 1, .d8s = d8s_dq },
      [0x89] = { .simd_size = simd_packed_int, .two_op = 1, .d8s = d8s_dq },
@@ -1875,6 +1876,7 @@ in_protmode(
  #define vcpu_has_hle()         (ctxt->cpuid->feat.hle)
  #define vcpu_has_avx2()        (ctxt->cpuid->feat.avx2)
  #define vcpu_has_bmi2()        (ctxt->cpuid->feat.bmi2)
+#define vcpu_has_invpcid()     (ctxt->cpuid->feat.invpcid)
  #define vcpu_has_rtm()         (ctxt->cpuid->feat.rtm)
  #define vcpu_has_mpx()         (ctxt->cpuid->feat.mpx)
  #define vcpu_has_avx512f()     (ctxt->cpuid->feat.avx512f)
@@ -9124,6 +9126,48 @@ x86_emulate(
          ASSERT(!state->simd_size);
          break;
  
+    case X86EMUL_OPC_66(0x0f38, 0x82): /* invpcid reg,m128 */
+        vcpu_must_have(invpcid);
+        generate_exception_if(ea.type != OP_MEM, EXC_UD);
+        generate_exception_if(!mode_ring0(), EXC_GP, 0);
+
+        if ( (rc = ops->read(ea.mem.seg, ea.mem.off, mmvalp, 16,
+                             ctxt)) != X86EMUL_OKAY )
+            goto done;
+
+        generate_exception_if(mmvalp->xmm[0] & ~0xfff, EXC_GP, 0);
+        dst.val = mode_64bit() ? *dst.reg : (uint32_t)*dst.reg;
+
+        switch ( dst.val )
+        {
+        case X86_INVPCID_TYPE_INDIV_ADDR:
+             generate_exception_if(!is_canonical_address(mmvalp->xmm[1]),
+                                   EXC_GP, 0);
+             /* fall through */
+        case X86_INVPCID_TYPE_SINGLE_CTXT:
+             if ( !mode_64bit() || !ops->read_cr )
+                 cr4 = 0;
+             else if ( (rc = ops->read_cr(4, &cr4, ctxt)) != X86EMUL_OKAY )
+                 goto done;
+             generate_exception_if(!(cr4 & X86_CR4_PCIDE) && mmvalp->xmm[0],
+                                   EXC_GP, 0);
+             break;
+        case X86_INVPCID_TYPE_ALL_INCL_GLOBAL:
+        case X86_INVPCID_TYPE_ALL_NON_GLOBAL:
+             break;
+        default:
+             generate_exception(EXC_GP, 0);
+        }
+
+        fail_if(!ops->tlb_op);
+        if ( (rc = ops->tlb_op(x86emul_invpcid, truncate_ea(mmvalp->xmm[1]),
+                               x86emul_invpcid_aux(mmvalp->xmm[0], dst.val),
+                               ctxt)) != X86EMUL_OKAY )
+            goto done;
+
+        state->simd_size = simd_none;
+        break;
+
      case X86EMUL_OPC_EVEX_66(0x0f38, 0x83): /* vpmultishiftqb [xyz]mm/mem,[xyz]mm,[xyz]mm{k} */
          generate_exception_if(!evex.w, EXC_UD);
          host_and_vcpu_must_have(avx512_vbmi);
--- a/xen/arch/x86/x86_emulate/x86_emulate.h
+++ b/xen/arch/x86/x86_emulate/x86_emulate.h
@@ -188,8 +188,26 @@ enum x86emul_cache_op {
  enum x86emul_tlb_op {
      x86emul_invlpg,
      x86emul_invlpga,
+    x86emul_invpcid,
  };
  
+static inline unsigned int x86emul_invpcid_aux(unsigned int pcid,
+                                            unsigned int type)
+{
+    ASSERT(!(pcid & ~0xfff));
+    return (type << 12) | pcid;
+}
+
+static inline unsigned int x86emul_invpcid_pcid(unsigned int aux)
+{
+    return aux & 0xfff;
+}
+
+static inline unsigned int x86emul_invpcid_type(unsigned int aux)
+{
+    return aux >> 12;
+}
+
  struct x86_emulate_state;
  
  /*
@@ -483,6 +501,8 @@ struct x86_emulate_ops
       * @addr and @aux have @op-specific meaning:
       * - INVLPG:  @aux:@addr represent seg:offset
       * - INVLPGA: @addr is the linear address, @aux the ASID
+     * - INVPCID: @addr is the linear address, @aux the combination of
+     *            PCID and type (see x86emul_invpcid_*()).
       */
      int (*tlb_op)(
          enum x86emul_tlb_op op,

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Re: [Xen-devel] [PATCH 5/6] x86emul: support INVPCID

Posted by Paul Durrant 2 weeks ago
> -----Original Message-----
> From: Jan Beulich <JBeulich@suse.com>
> Sent: 01 July 2019 12:58
> To: xen-devel@lists.xenproject.org
> Cc: Andrew Cooper <Andrew.Cooper3@citrix.com>; Paul Durrant <Paul.Durrant@citrix.com>; Roger Pau Monne
> <roger.pau@citrix.com>; Wei Liu <wl@xen.org>
> Subject: [PATCH 5/6] x86emul: support INVPCID
> 
> Just like for INVLPGA the HVM hook only supports PCID 0 for the time
> being for individual address invalidation. It also translates the other
> types to a full flush, which is architecturally permitted and
> performance-wise presumably not much worse because emulation is slow
> anyway.
> 
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

hvm/emulate bits...

Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
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[Xen-devel] [PATCH 6/6] x86emul: support MOVDIR{I,64B} insns

Posted by Jan Beulich 2 weeks ago
Note that the ISA extensions document revision 035 doesn't specify
exception behavior for ModRM.mod != 0b11; assuming #UD here.

Signed-off-by: Jan Beulich <jbeulich@suse.com>

--- a/xen/arch/x86/x86_emulate/x86_emulate.c
+++ b/xen/arch/x86/x86_emulate/x86_emulate.c
@@ -548,6 +548,8 @@ static const struct ext0f38_table {
      [0xf1] = { .to_mem = 1, .two_op = 1 },
      [0xf2 ... 0xf3] = {},
      [0xf5 ... 0xf7] = {},
+    [0xf8] = { .simd_size = simd_other },
+    [0xf9] = { .to_mem = 1 },
  };
  
  /* Shift values between src and dst sizes of pmov{s,z}x{b,w,d}{w,d,q}. */
@@ -1902,6 +1904,8 @@ in_protmode(
  #define vcpu_has_avx512_bitalg() (ctxt->cpuid->feat.avx512_bitalg)
  #define vcpu_has_avx512_vpopcntdq() (ctxt->cpuid->feat.avx512_vpopcntdq)
  #define vcpu_has_rdpid()       (ctxt->cpuid->feat.rdpid)
+#define vcpu_has_movdiri()     (ctxt->cpuid->feat.movdiri)
+#define vcpu_has_movdir64b()   (ctxt->cpuid->feat.movdir64b)
  #define vcpu_has_avx512_4vnniw() (ctxt->cpuid->feat.avx512_4vnniw)
  #define vcpu_has_avx512_4fmaps() (ctxt->cpuid->feat.avx512_4fmaps)
  
@@ -2693,10 +2697,12 @@ x86_decode_0f38(
      {
      case 0x00 ... 0xef:
      case 0xf2 ... 0xf5:
-    case 0xf7 ... 0xff:
+    case 0xf7 ... 0xf8:
+    case 0xfa ... 0xff:
          op_bytes = 0;
          /* fall through */
      case 0xf6: /* adcx / adox */
+    case 0xf9: /* movdiri */
          ctxt->opcode |= MASK_INSR(vex.pfx, X86EMUL_OPC_PFX_MASK);
          break;
  
@@ -9896,6 +9902,32 @@ x86_emulate(
                              : "0" ((uint32_t)src.val), "rm" (_regs.edx) );
          break;
  
+    case X86EMUL_OPC_66(0x0f38, 0xf8): /* movdir64b r,m512 */
+        vcpu_must_have(movdir64b);
+        generate_exception_if(ea.type != OP_MEM, EXC_UD);
+        src.val = truncate_ea(*dst.reg);
+        generate_exception_if(!is_aligned(x86_seg_es, src.val, 64, ctxt, ops),
+                              EXC_GP, 0);
+        /* Ignore the non-temporal behavior for now. */
+        fail_if(!ops->write);
+        BUILD_BUG_ON(sizeof(*mmvalp) < 64);
+        if ( (rc = ops->read(ea.mem.seg, ea.mem.off, mmvalp, 64,
+                             ctxt)) != X86EMUL_OKAY ||
+             (rc = ops->write(x86_seg_es, src.val, mmvalp, 64,
+                              ctxt)) != X86EMUL_OKAY )
+            goto done;
+        state->simd_size = simd_none;
+        sfence = true;
+        break;
+
+    case X86EMUL_OPC(0x0f38, 0xf9): /* movdiri mem,r */
+        vcpu_must_have(movdiri);
+        generate_exception_if(dst.type != OP_MEM, EXC_UD);
+        /* Ignore the non-temporal behavior for now. */
+        dst.val = src.val;
+        sfence = true;
+        break;
+
      case X86EMUL_OPC_VEX_66(0x0f3a, 0x00): /* vpermq $imm8,ymm/m256,ymm */
      case X86EMUL_OPC_VEX_66(0x0f3a, 0x01): /* vpermpd $imm8,ymm/m256,ymm */
          generate_exception_if(!vex.l || !vex.w, EXC_UD);
--- a/xen/include/public/arch-x86/cpufeatureset.h
+++ b/xen/include/public/arch-x86/cpufeatureset.h
@@ -237,6 +237,8 @@ XEN_CPUFEATURE(AVX512_BITALG, 6*32+12) /
  XEN_CPUFEATURE(AVX512_VPOPCNTDQ, 6*32+14) /*A  POPCNT for vectors of DW/QW */
  XEN_CPUFEATURE(RDPID,         6*32+22) /*A  RDPID instruction */
  XEN_CPUFEATURE(CLDEMOTE,      6*32+25) /*A  CLDEMOTE instruction */
+XEN_CPUFEATURE(MOVDIRI,       6*32+27) /*A  MOVDIRI instruction */
+XEN_CPUFEATURE(MOVDIR64B,     6*32+28) /*A  MOVDIR64B instruction */
  
  /* AMD-defined CPU features, CPUID level 0x80000007.edx, word 7 */
  XEN_CPUFEATURE(ITSC,          7*32+ 8) /*   Invariant TSC */
--- a/tools/tests/x86_emulator/test_x86_emulator.c
+++ b/tools/tests/x86_emulator/test_x86_emulator.c
@@ -2196,6 +2196,36 @@ int main(int argc, char **argv)
          goto fail;
      printf("okay\n");
  
+    printf("%-40s", "Testing movdiri %edx,(%ecx)...");
+    instr[0] = 0x0f; instr[1] = 0x38; instr[2] = 0xf9; instr[3] = 0x11;
+    regs.eip = (unsigned long)&instr[0];
+    regs.ecx = (unsigned long)memset(res, -1, 16);
+    regs.edx = 0x44332211;
+    rc = x86_emulate(&ctxt, &emulops);
+    if ( (rc != X86EMUL_OKAY) ||
+         (regs.eip != (unsigned long)&instr[4]) ||
+         res[0] != 0x44332211 || ~res[1] )
+        goto fail;
+    printf("okay\n");
+
+    printf("%-40s", "Testing movdir64b 144(%edx),%ecx...");
+    instr[0] = 0x66; instr[1] = 0x0f; instr[2] = 0x38; instr[3] = 0xf8;
+    instr[4] = 0x8a; instr[5] = 0x90; instr[8] = instr[7] = instr[6] = 0;
+    regs.eip = (unsigned long)&instr[0];
+    for ( i = 0; i < 64; ++i )
+        res[i] = i - 20;
+    regs.edx = (unsigned long)res;
+    regs.ecx = (unsigned long)(res + 16);
+    rc = x86_emulate(&ctxt, &emulops);
+    if ( (rc != X86EMUL_OKAY) ||
+         (regs.eip != (unsigned long)&instr[9]) ||
+         res[15] != -5 || res[32] != 12 )
+        goto fail;
+    for ( i = 16; i < 32; ++i )
+        if ( res[i] != i )
+            goto fail;
+    printf("okay\n");
+
      printf("%-40s", "Testing movq %mm3,(%ecx)...");
      if ( stack_exec && cpu_has_mmx )
      {
--- a/tools/tests/x86_emulator/x86-emulate.c
+++ b/tools/tests/x86_emulator/x86-emulate.c
@@ -76,6 +76,8 @@ bool emul_test_init(void)
      cp.feat.adx = true;
      cp.feat.avx512pf = cp.feat.avx512f;
      cp.feat.rdpid = true;
+    cp.feat.movdiri = true;
+    cp.feat.movdir64b = true;
      cp.extd.clzero = true;
  
      if ( cpu_has_xsave )
@@ -137,15 +139,15 @@ int emul_test_cpuid(
          res->c |= 1U << 22;
  
      /*
-     * The emulator doesn't itself use ADCX/ADOX/RDPID nor the S/G prefetch
-     * insns, so we can always run the respective tests.
+     * The emulator doesn't itself use ADCX/ADOX/RDPID/MOVDIR* nor the S/G
+     * prefetch insns, so we can always run the respective tests.
       */
      if ( leaf == 7 && subleaf == 0 )
      {
          res->b |= (1U << 10) | (1U << 19);
          if ( res->b & (1U << 16) )
              res->b |= 1U << 26;
-        res->c |= 1U << 22;
+        res->c |= (1U << 22) | (1U << 27) | (1U << 28);
      }
  
      /*

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