[PATCH v3 0/3] Misc changes for few VMCB bits

[PATCH v3 0/3] Misc changes for few VMCB bits

[Vaishali Thakkar]

Hi,

In this patchset, first & second patch removes the unnecessary
suffix from a bunch of vmcb bits. Third patch is about printing
the status of sev and sev-es bits while dumping VMCB.

Changes since v1:
  - Address comments from Andrew and Jan
  - Add extrapatch to drop the suffix _guest as per Andrew's
    suggestion in one of the reviews
  - Address Andrew's comment with respect to pretty printing

Changes since v2:
  - Use VMCB accessors instead of open coding in patch 1 & 2
  - Fix one remaining instance of using false/true instead of
    0/1 in patch 2
  - Improve the pretty printing in svm-debug based on Jan's
    comments
  - Improve commit logs and the subject of patch 3 to include
    the changes done in v3

Vaishali Thakkar (3):
  x86/svm: Drop the _enabled suffix from vmcb bits
  x86/svm: Drop the suffix _guest from vmcb bit
  x86/svmdebug: Print np, sev and sev_es vmcb bits

 xen/arch/x86/hvm/svm/asid.c                  |  6 ++---
 xen/arch/x86/hvm/svm/nestedsvm.c             | 22 ++++++++---------
 xen/arch/x86/hvm/svm/svm.c                   |  2 +-
 xen/arch/x86/hvm/svm/svmdebug.c              |  7 ++++--
 xen/arch/x86/hvm/svm/vmcb.c                  |  2 +-
 xen/arch/x86/include/asm/hvm/svm/nestedsvm.h |  2 +-
 xen/arch/x86/include/asm/hvm/svm/vmcb.h      | 26 ++++++++++----------
 7 files changed, 35 insertions(+), 32 deletions(-)

-- 
2.44.0

[PATCH v3 1/3] x86/svm: Drop the _enabled suffix from vmcb bits

[Vaishali Thakkar]

The suffix is redundant for np/sev/sev-es bits. Drop it
to avoid adding extra code volume.

Also, while we're here, drop the double negations in one
of the instances of _np bit, replace 0/1 with false/true
in the use cases of _np and use VMCB accessors instead
of open coding.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Vaishali Thakkar <vaishali.thakkar@vates.tech>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
Changes since v1:
        - Address Andrew and Jan's reviews related to dropping
          double negation and replacing 0/1 with false/true
        - Fix the typo around signed-off-by
Changes since v2:
        - Use VMCB accessors instead of open coding for the
          code that's touched by this commit
---
 xen/arch/x86/hvm/svm/nestedsvm.c        | 14 +++++++-------
 xen/arch/x86/hvm/svm/svm.c              |  2 +-
 xen/arch/x86/hvm/svm/vmcb.c             |  2 +-
 xen/arch/x86/include/asm/hvm/svm/vmcb.h | 20 ++++++++++----------
 4 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/xen/arch/x86/hvm/svm/nestedsvm.c b/xen/arch/x86/hvm/svm/nestedsvm.c
index e4e01add8c..07630d74d3 100644
--- a/xen/arch/x86/hvm/svm/nestedsvm.c
+++ b/xen/arch/x86/hvm/svm/nestedsvm.c
@@ -571,7 +571,7 @@ static int nsvm_vmcb_prepare4vmrun(struct vcpu *v, struct cpu_user_regs *regs)
     if ( nestedhvm_paging_mode_hap(v) )
     {
         /* host nested paging + guest nested paging. */
-        n2vmcb->_np_enable = 1;
+        vmcb_set_np(n2vmcb, true);
 
         nestedsvm_vmcb_set_nestedp2m(v, ns_vmcb, n2vmcb);
 
@@ -585,7 +585,7 @@ static int nsvm_vmcb_prepare4vmrun(struct vcpu *v, struct cpu_user_regs *regs)
     else if ( paging_mode_hap(v->domain) )
     {
         /* host nested paging + guest shadow paging. */
-        n2vmcb->_np_enable = 1;
+        vmcb_set_np(n2vmcb, true);
         /* Keep h_cr3 as it is. */
         n2vmcb->_h_cr3 = n1vmcb->_h_cr3;
         /* When l1 guest does shadow paging
@@ -601,7 +601,7 @@ static int nsvm_vmcb_prepare4vmrun(struct vcpu *v, struct cpu_user_regs *regs)
     else
     {
         /* host shadow paging + guest shadow paging. */
-        n2vmcb->_np_enable = 0;
+        vmcb_set_np(n2vmcb, false);
         n2vmcb->_h_cr3 = 0x0;
 
         /* TODO: Once shadow-shadow paging is in place come back to here
@@ -706,7 +706,7 @@ nsvm_vcpu_vmentry(struct vcpu *v, struct cpu_user_regs *regs,
     }
 
     /* nested paging for the guest */
-    svm->ns_hap_enabled = !!ns_vmcb->_np_enable;
+    svm->ns_hap_enabled = vmcb_get_np(ns_vmcb);
 
     /* Remember the V_INTR_MASK in hostflags */
     svm->ns_hostflags.fields.vintrmask = !!ns_vmcb->_vintr.fields.intr_masking;
@@ -1084,7 +1084,7 @@ nsvm_vmcb_prepare4vmexit(struct vcpu *v, struct cpu_user_regs *regs)
     if ( nestedhvm_paging_mode_hap(v) )
     {
         /* host nested paging + guest nested paging. */
-        ns_vmcb->_np_enable = n2vmcb->_np_enable;
+        vmcb_set_np(ns_vmcb, vmcb_get_np(n2vmcb));
         ns_vmcb->_cr3 = n2vmcb->_cr3;
         /* The vmcb->h_cr3 is the shadowed h_cr3. The original
          * unshadowed guest h_cr3 is kept in ns_vmcb->h_cr3,
@@ -1093,7 +1093,7 @@ nsvm_vmcb_prepare4vmexit(struct vcpu *v, struct cpu_user_regs *regs)
     else if ( paging_mode_hap(v->domain) )
     {
         /* host nested paging + guest shadow paging. */
-        ns_vmcb->_np_enable = 0;
+        vmcb_set_np(ns_vmcb, false);
         /* Throw h_cr3 away. Guest is not allowed to set it or
          * it can break out, otherwise (security hole!) */
         ns_vmcb->_h_cr3 = 0x0;
@@ -1104,7 +1104,7 @@ nsvm_vmcb_prepare4vmexit(struct vcpu *v, struct cpu_user_regs *regs)
     else
     {
         /* host shadow paging + guest shadow paging. */
-        ns_vmcb->_np_enable = 0;
+        vmcb_set_np(ns_vmcb, false);
         ns_vmcb->_h_cr3 = 0x0;
         /* The vmcb->_cr3 is the shadowed cr3. The original
          * unshadowed guest cr3 is kept in ns_vmcb->_cr3,
diff --git a/xen/arch/x86/hvm/svm/svm.c b/xen/arch/x86/hvm/svm/svm.c
index b551eac807..b1ab0b568b 100644
--- a/xen/arch/x86/hvm/svm/svm.c
+++ b/xen/arch/x86/hvm/svm/svm.c
@@ -473,7 +473,7 @@ static int svm_vmcb_restore(struct vcpu *v, struct hvm_hw_cpu *c)
 
     if ( paging_mode_hap(v->domain) )
     {
-        vmcb_set_np_enable(vmcb, 1);
+        vmcb_set_np(vmcb, true);
         vmcb_set_g_pat(vmcb, MSR_IA32_CR_PAT_RESET /* guest PAT */);
         vmcb_set_h_cr3(vmcb, pagetable_get_paddr(p2m_get_pagetable(p2m)));
     }
diff --git a/xen/arch/x86/hvm/svm/vmcb.c b/xen/arch/x86/hvm/svm/vmcb.c
index 282fe7cdbe..4e1f61dbe0 100644
--- a/xen/arch/x86/hvm/svm/vmcb.c
+++ b/xen/arch/x86/hvm/svm/vmcb.c
@@ -133,7 +133,7 @@ static int construct_vmcb(struct vcpu *v)
 
     if ( paging_mode_hap(v->domain) )
     {
-        vmcb->_np_enable = 1; /* enable nested paging */
+        vmcb_set_np(vmcb, true); /* enable nested paging */
         vmcb->_g_pat = MSR_IA32_CR_PAT_RESET; /* guest PAT */
         vmcb->_h_cr3 = pagetable_get_paddr(
             p2m_get_pagetable(p2m_get_hostp2m(v->domain)));
diff --git a/xen/arch/x86/include/asm/hvm/svm/vmcb.h b/xen/arch/x86/include/asm/hvm/svm/vmcb.h
index 91221ff4e2..bf2b8d9a94 100644
--- a/xen/arch/x86/include/asm/hvm/svm/vmcb.h
+++ b/xen/arch/x86/include/asm/hvm/svm/vmcb.h
@@ -385,7 +385,7 @@ typedef union
         bool iopm:1;       /* 1:  iopm_base_pa, msrpm_base_pa */
         bool asid:1;       /* 2:  guest_asid */
         bool tpr:1;        /* 3:  vintr */
-        bool np:1;         /* 4:  np_enable, h_cr3, g_pat */
+        bool np:1;         /* 4:  np, h_cr3, g_pat */
         bool cr:1;         /* 5:  cr0, cr3, cr4, efer */
         bool dr:1;         /* 6:  dr6, dr7 */
         bool dt:1;         /* 7:  gdtr, idtr */
@@ -473,12 +473,12 @@ struct vmcb_struct {
     intinfo_t exit_int_info;    /* offset 0x88 */
     union {                     /* offset 0x90 - cleanbit 4 */
         struct {
-            bool _np_enable     :1;
-            bool _sev_enable    :1;
-            bool _sev_es_enable :1;
-            bool _gmet          :1;
-            bool _np_sss        :1;
-            bool _vte           :1;
+            bool _np        :1;
+            bool _sev       :1;
+            bool _sev_es    :1;
+            bool _gmet      :1;
+            bool _np_sss    :1;
+            bool _vte       :1;
         };
         uint64_t _np_ctrl;
     };
@@ -645,9 +645,9 @@ VMCB_ACCESSORS(msrpm_base_pa, iopm)
 VMCB_ACCESSORS(guest_asid, asid)
 VMCB_ACCESSORS(vintr, tpr)
 VMCB_ACCESSORS(np_ctrl, np)
-VMCB_ACCESSORS_(np_enable, bool, np)
-VMCB_ACCESSORS_(sev_enable, bool, np)
-VMCB_ACCESSORS_(sev_es_enable, bool, np)
+VMCB_ACCESSORS_(np, bool, np)
+VMCB_ACCESSORS_(sev, bool, np)
+VMCB_ACCESSORS_(sev_es, bool, np)
 VMCB_ACCESSORS_(gmet, bool, np)
 VMCB_ACCESSORS_(vte, bool, np)
 VMCB_ACCESSORS(h_cr3, np)
-- 
2.44.0

[PATCH v3 2/3] x86/svm: Drop the suffix _guest from vmcb bit

[Vaishali Thakkar]

The suffix _guest is redundant for asid bit. Drop it
to avoid adding extra code volume.

While we're here, replace 0/1 with false/true and use
VMCB accessors instead of open coding.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Vaishali Thakkar <vaishali.thakkar@vates.tech>
---
Changes since v1:
        - This patch wasn't part of v1. It's been added to
          address Andrew's suggestion.
Changes since v2:
        - replace 0/1 with false/true in one of the instance
        - Use VMCB accessors instead of open coding
---
 xen/arch/x86/hvm/svm/asid.c                  | 6 +++---
 xen/arch/x86/hvm/svm/nestedsvm.c             | 8 ++++----
 xen/arch/x86/hvm/svm/svmdebug.c              | 4 ++--
 xen/arch/x86/include/asm/hvm/svm/nestedsvm.h | 2 +-
 xen/arch/x86/include/asm/hvm/svm/vmcb.h      | 6 +++---
 5 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/xen/arch/x86/hvm/svm/asid.c b/xen/arch/x86/hvm/svm/asid.c
index 28e0dbc176..39e3c56919 100644
--- a/xen/arch/x86/hvm/svm/asid.c
+++ b/xen/arch/x86/hvm/svm/asid.c
@@ -37,14 +37,14 @@ void svm_asid_handle_vmrun(void)
     /* ASID 0 indicates that ASIDs are disabled. */
     if ( p_asid->asid == 0 )
     {
-        vmcb_set_guest_asid(vmcb, 1);
+        vmcb_set_asid(vmcb,true);
         vmcb->tlb_control =
             cpu_has_svm_flushbyasid ? TLB_CTRL_FLUSH_ASID : TLB_CTRL_FLUSH_ALL;
         return;
     }
 
-    if ( vmcb_get_guest_asid(vmcb) != p_asid->asid )
-        vmcb_set_guest_asid(vmcb, p_asid->asid);
+    if ( vmcb_get_asid(vmcb) != p_asid->asid )
+        vmcb_set_asid(vmcb, p_asid->asid);
 
     vmcb->tlb_control =
         !need_flush ? TLB_CTRL_NO_FLUSH :
diff --git a/xen/arch/x86/hvm/svm/nestedsvm.c b/xen/arch/x86/hvm/svm/nestedsvm.c
index 07630d74d3..a8d5f4ee95 100644
--- a/xen/arch/x86/hvm/svm/nestedsvm.c
+++ b/xen/arch/x86/hvm/svm/nestedsvm.c
@@ -157,7 +157,7 @@ int cf_check nsvm_vcpu_reset(struct vcpu *v)
     svm->ns_hap_enabled = 0;
     svm->ns_vmcb_guestcr3 = 0;
     svm->ns_vmcb_hostcr3 = 0;
-    svm->ns_guest_asid = 0;
+    svm->ns_asid = 0;
     svm->ns_hostflags.bytes = 0;
     svm->ns_vmexit.exitinfo1 = 0;
     svm->ns_vmexit.exitinfo2 = 0;
@@ -698,11 +698,11 @@ nsvm_vcpu_vmentry(struct vcpu *v, struct cpu_user_regs *regs,
     /* Convert explicitely to boolean. Deals with l1 guests
      * that use flush-by-asid w/o checking the cpuid bits */
     nv->nv_flushp2m = !!ns_vmcb->tlb_control;
-    if ( svm->ns_guest_asid != ns_vmcb->_guest_asid )
+    if ( svm->ns_asid != vmcb_get_asid(ns_vmcb))
     {
         nv->nv_flushp2m = 1;
         hvm_asid_flush_vcpu_asid(&vcpu_nestedhvm(v).nv_n2asid);
-        svm->ns_guest_asid = ns_vmcb->_guest_asid;
+        svm->ns_asid = vmcb_get_asid(ns_vmcb);
     }
 
     /* nested paging for the guest */
@@ -1046,7 +1046,7 @@ nsvm_vmcb_prepare4vmexit(struct vcpu *v, struct cpu_user_regs *regs)
     /* Keep it. It's maintainted by the l1 guest. */
 
     /* ASID */
-    /* ns_vmcb->_guest_asid = n2vmcb->_guest_asid; */
+    /* vmcb_set_asid(ns_vmcb, vmcb_get_asid(n2vmcb)); */
 
     /* TLB control */
     ns_vmcb->tlb_control = 0;
diff --git a/xen/arch/x86/hvm/svm/svmdebug.c b/xen/arch/x86/hvm/svm/svmdebug.c
index 24358c6eea..0d714c728c 100644
--- a/xen/arch/x86/hvm/svm/svmdebug.c
+++ b/xen/arch/x86/hvm/svm/svmdebug.c
@@ -51,8 +51,8 @@ void svm_vmcb_dump(const char *from, const struct vmcb_struct *vmcb)
            vmcb->exitcode, vmcb->exit_int_info.raw);
     printk("exitinfo1 = %#"PRIx64" exitinfo2 = %#"PRIx64"\n",
            vmcb->exitinfo1, vmcb->exitinfo2);
-    printk("np_ctrl = %#"PRIx64" guest_asid = %#x\n",
-           vmcb_get_np_ctrl(vmcb), vmcb_get_guest_asid(vmcb));
+    printk("np_ctrl = %#"PRIx64" asid = %#x\n",
+           vmcb_get_np_ctrl(vmcb), vmcb_get_asid(vmcb));
     printk("virtual vmload/vmsave = %d, virt_ext = %#"PRIx64"\n",
            vmcb->virt_ext.fields.vloadsave_enable, vmcb->virt_ext.bytes);
     printk("cpl = %d efer = %#"PRIx64" star = %#"PRIx64" lstar = %#"PRIx64"\n",
diff --git a/xen/arch/x86/include/asm/hvm/svm/nestedsvm.h b/xen/arch/x86/include/asm/hvm/svm/nestedsvm.h
index 406fc082b1..7767cd6080 100644
--- a/xen/arch/x86/include/asm/hvm/svm/nestedsvm.h
+++ b/xen/arch/x86/include/asm/hvm/svm/nestedsvm.h
@@ -51,7 +51,7 @@ struct nestedsvm {
      *     the l1 guest nested page table
      */
     uint64_t ns_vmcb_guestcr3, ns_vmcb_hostcr3;
-    uint32_t ns_guest_asid;
+    uint32_t ns_asid;
 
     bool ns_hap_enabled;
 
diff --git a/xen/arch/x86/include/asm/hvm/svm/vmcb.h b/xen/arch/x86/include/asm/hvm/svm/vmcb.h
index bf2b8d9a94..0396d10b90 100644
--- a/xen/arch/x86/include/asm/hvm/svm/vmcb.h
+++ b/xen/arch/x86/include/asm/hvm/svm/vmcb.h
@@ -383,7 +383,7 @@ typedef union
         bool intercepts:1; /* 0:  cr/dr/exception/general intercepts,
                             *     pause_filter_count, tsc_offset */
         bool iopm:1;       /* 1:  iopm_base_pa, msrpm_base_pa */
-        bool asid:1;       /* 2:  guest_asid */
+        bool asid:1;       /* 2:  asid */
         bool tpr:1;        /* 3:  vintr */
         bool np:1;         /* 4:  np, h_cr3, g_pat */
         bool cr:1;         /* 5:  cr0, cr3, cr4, efer */
@@ -413,7 +413,7 @@ struct vmcb_struct {
     u64 _iopm_base_pa;          /* offset 0x40 - cleanbit 1 */
     u64 _msrpm_base_pa;         /* offset 0x48 - cleanbit 1 */
     u64 _tsc_offset;            /* offset 0x50 - cleanbit 0 */
-    u32 _guest_asid;            /* offset 0x58 - cleanbit 2 */
+    u32 _asid;                  /* offset 0x58 - cleanbit 2 */
     u8  tlb_control;            /* offset 0x5C - TLB_CTRL_* */
     u8  res07[3];
     vintr_t _vintr;             /* offset 0x60 - cleanbit 3 */
@@ -642,7 +642,7 @@ VMCB_ACCESSORS(pause_filter_thresh, intercepts)
 VMCB_ACCESSORS(tsc_offset, intercepts)
 VMCB_ACCESSORS(iopm_base_pa, iopm)
 VMCB_ACCESSORS(msrpm_base_pa, iopm)
-VMCB_ACCESSORS(guest_asid, asid)
+VMCB_ACCESSORS(asid, asid)
 VMCB_ACCESSORS(vintr, tpr)
 VMCB_ACCESSORS(np_ctrl, np)
 VMCB_ACCESSORS_(np, bool, np)
-- 
2.44.0

Re: [PATCH v3 2/3] x86/svm: Drop the suffix _guest from vmcb bit

[Jan Beulich]

On 13.03.2024 17:41, Vaishali Thakkar wrote:
> The suffix _guest is redundant for asid bit. Drop it
> to avoid adding extra code volume.
> 
> While we're here, replace 0/1 with false/true and use
> VMCB accessors instead of open coding.
> 
> Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
> Signed-off-by: Vaishali Thakkar <vaishali.thakkar@vates.tech>

Reviewed-by: Jan Beulich <jbeulich@suse.com>
with ...

> --- a/xen/arch/x86/hvm/svm/asid.c
> +++ b/xen/arch/x86/hvm/svm/asid.c
> @@ -37,14 +37,14 @@ void svm_asid_handle_vmrun(void)
>      /* ASID 0 indicates that ASIDs are disabled. */
>      if ( p_asid->asid == 0 )
>      {
> -        vmcb_set_guest_asid(vmcb, 1);
> +        vmcb_set_asid(vmcb,true);

... the blank put back that was lost here (can be done while committing).

Jan

Re: [PATCH v3 2/3] x86/svm: Drop the suffix _guest from vmcb bit

[Vaishali Thakkar]

On 3/14/24 17:04, Jan Beulich wrote:
> On 13.03.2024 17:41, Vaishali Thakkar wrote:
>> The suffix _guest is redundant for asid bit. Drop it
>> to avoid adding extra code volume.
>>
>> While we're here, replace 0/1 with false/true and use
>> VMCB accessors instead of open coding.
>>
>> Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
>> Signed-off-by: Vaishali Thakkar <vaishali.thakkar@vates.tech>
> 
> Reviewed-by: Jan Beulich <jbeulich@suse.com>
> with ...
> 
>> --- a/xen/arch/x86/hvm/svm/asid.c
>> +++ b/xen/arch/x86/hvm/svm/asid.c
>> @@ -37,14 +37,14 @@ void svm_asid_handle_vmrun(void)
>>       /* ASID 0 indicates that ASIDs are disabled. */
>>       if ( p_asid->asid == 0 )
>>       {
>> -        vmcb_set_guest_asid(vmcb, 1);
>> +        vmcb_set_asid(vmcb,true);
> 
> ... the blank put back that was lost here (can be done while committing).

Thanks

> Jan

[PATCH v3 3/3] x86/svmdebug: Print np, sev and sev_es vmcb bits

[Vaishali Thakkar]

Currently only raw _np_ctrl is being printed. It can
be informational to know about which particular bits
are enabled. So, this commit adds the bit-by-bit decode
for np, sev and sev_es bits.

Note that while, only np is enabled in certain scenarios
at the moment, work for enabling sev and sev_es is in
progress. And it'll be useful to have this information as
part of svmdebug.

Signed-off-by: Vaishali Thakkar <vaishali.thakkar@vates.tech>
---
Changes since v1:
        - Pretty printing
Changes since v2:
        - Minor changes in pretty printing to make information
          clear
        - Improve commit log and subject to include _np bit
---
 xen/arch/x86/hvm/svm/svmdebug.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/xen/arch/x86/hvm/svm/svmdebug.c b/xen/arch/x86/hvm/svm/svmdebug.c
index 0d714c728c..9d3badcf5d 100644
--- a/xen/arch/x86/hvm/svm/svmdebug.c
+++ b/xen/arch/x86/hvm/svm/svmdebug.c
@@ -51,8 +51,11 @@ void svm_vmcb_dump(const char *from, const struct vmcb_struct *vmcb)
            vmcb->exitcode, vmcb->exit_int_info.raw);
     printk("exitinfo1 = %#"PRIx64" exitinfo2 = %#"PRIx64"\n",
            vmcb->exitinfo1, vmcb->exitinfo2);
-    printk("np_ctrl = %#"PRIx64" asid = %#x\n",
-           vmcb_get_np_ctrl(vmcb), vmcb_get_asid(vmcb));
+    printk("asid = %#x np_ctrl = %#"PRIx64":%s%s%s\n",
+           vmcb_get_asid(vmcb), vmcb_get_np_ctrl(vmcb),
+           vmcb_get_np(vmcb)     ? " NP"     : "",
+           vmcb_get_sev(vmcb)    ? " SEV"    : "",
+           vmcb_get_sev_es(vmcb) ? " SEV_ES" : "");
     printk("virtual vmload/vmsave = %d, virt_ext = %#"PRIx64"\n",
            vmcb->virt_ext.fields.vloadsave_enable, vmcb->virt_ext.bytes);
     printk("cpl = %d efer = %#"PRIx64" star = %#"PRIx64" lstar = %#"PRIx64"\n",
-- 
2.44.0

Re: [PATCH v3 3/3] x86/svmdebug: Print np, sev and sev_es vmcb bits

[Jan Beulich]

On 13.03.2024 17:41, Vaishali Thakkar wrote:
> Currently only raw _np_ctrl is being printed. It can
> be informational to know about which particular bits
> are enabled. So, this commit adds the bit-by-bit decode
> for np, sev and sev_es bits.
> 
> Note that while, only np is enabled in certain scenarios
> at the moment, work for enabling sev and sev_es is in
> progress. And it'll be useful to have this information as
> part of svmdebug.
> 
> Signed-off-by: Vaishali Thakkar <vaishali.thakkar@vates.tech>

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