[PATCH 0/6] convert more Xen page table code to the new API

[PATCH 0/6] convert more Xen page table code to the new API

[Hongyan Xia]

From: Hongyan Xia <hongyxia@amazon.com>

Basically just rewriting functions using the new API to map and unmap
PTEs. Each patch is independent.

Apart from mapping and unmapping page tables, no other functional change
intended.

Wei Liu (6):
  x86_64/mm: map and unmap page tables in cleanup_frame_table
  x86_64/mm: map and unmap page tables in subarch_init_memory
  x86_64/mm: map and unmap page tables in subarch_memory_op
  x86/smpboot: map and unmap page tables in cleanup_cpu_root_pgt
  x86/pv: map and unmap page tables in mark_pv_pt_pages_rdonly
  x86/pv: map and unmap page table in dom0_construct_pv

 xen/arch/x86/pv/dom0_build.c | 38 ++++++++++++++++++++++++------------
 xen/arch/x86/smpboot.c       | 25 ++++++++++++++++--------
 xen/arch/x86/x86_64/mm.c     | 32 +++++++++++++++---------------
 3 files changed, 58 insertions(+), 37 deletions(-)

-- 
2.24.1.AMZN

[PATCH 1/6] x86_64/mm: map and unmap page tables in cleanup_frame_table

[Hongyan Xia]

From: Wei Liu <wei.liu2@citrix.com>

Also fix a weird indentation.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
---
 xen/arch/x86/x86_64/mm.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c
index e85ef449f3..18210405f4 100644
--- a/xen/arch/x86/x86_64/mm.c
+++ b/xen/arch/x86/x86_64/mm.c
@@ -737,8 +737,8 @@ static void cleanup_frame_table(struct mem_hotadd_info *info)
 
     while (sva < eva)
     {
-        l3e = l4e_to_l3e(idle_pg_table[l4_table_offset(sva)])[
-          l3_table_offset(sva)];
+        l3e = l3e_from_l4e(idle_pg_table[l4_table_offset(sva)],
+                           l3_table_offset(sva));
         if ( !(l3e_get_flags(l3e) & _PAGE_PRESENT) ||
              (l3e_get_flags(l3e) & _PAGE_PSE) )
         {
@@ -747,7 +747,7 @@ static void cleanup_frame_table(struct mem_hotadd_info *info)
             continue;
         }
 
-        l2e = l3e_to_l2e(l3e)[l2_table_offset(sva)];
+        l2e = l2e_from_l3e(l3e, l2_table_offset(sva));
         ASSERT(l2e_get_flags(l2e) & _PAGE_PRESENT);
 
         if ( (l2e_get_flags(l2e) & (_PAGE_PRESENT | _PAGE_PSE)) ==
@@ -763,10 +763,10 @@ static void cleanup_frame_table(struct mem_hotadd_info *info)
             continue;
         }
 
-        ASSERT(l1e_get_flags(l2e_to_l1e(l2e)[l1_table_offset(sva)]) &
-                _PAGE_PRESENT);
-         sva = (sva & ~((1UL << PAGE_SHIFT) - 1)) +
-                    (1UL << PAGE_SHIFT);
+        ASSERT(l1e_get_flags(l1e_from_l2e(l2e, l1_table_offset(sva))) &
+               _PAGE_PRESENT);
+
+        sva = (sva & ~((1UL << PAGE_SHIFT) - 1)) + (1UL << PAGE_SHIFT);
     }
 
     /* Brute-Force flush all TLB */
-- 
2.24.1.AMZN

Re: [PATCH 1/6] x86_64/mm: map and unmap page tables in cleanup_frame_table

[Julien Grall]

Hi,

On 17/04/2020 10:52, Hongyan Xia wrote:> diff --git 
a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c> index 
e85ef449f3..18210405f4 100644> --- a/xen/arch/x86/x86_64/mm.c> +++ 
b/xen/arch/x86/x86_64/mm.c> @@ -737,8 +737,8 @@ static void 
cleanup_frame_table(struct mem_hotadd_info *info)>   >       while (sva 
< eva)>       {> -        l3e = 
l4e_to_l3e(idle_pg_table[l4_table_offset(sva)])[> - 
l3_table_offset(sva)];> +        l3e = 
l3e_from_l4e(idle_pg_table[l4_table_offset(sva)],> + 
       l3_table_offset(sva));
This macro doesn't exist yet in the tree. It would be good to spell out 
the dependencies in the cover letter so this doesn't get merged before 
the dependency is merged.

Reviewed-by: Julien Grall <jgrall@amazon.com>

Cheers,

-- 
Julien Grall

Re: [PATCH 1/6] x86_64/mm: map and unmap page tables in cleanup_frame_table

[Julien Grall]

On 24/04/2020 09:58, Julien Grall wrote:
> Hi,
> 
> On 17/04/2020 10:52, Hongyan Xia wrote:> diff --git 
> a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c> index 
> e85ef449f3..18210405f4 100644> --- a/xen/arch/x86/x86_64/mm.c> +++ 
> b/xen/arch/x86/x86_64/mm.c> @@ -737,8 +737,8 @@ static void 
> cleanup_frame_table(struct mem_hotadd_info *info)>   >       while (sva 
> < eva)>       {> -        l3e = 
> l4e_to_l3e(idle_pg_table[l4_table_offset(sva)])[> - 
> l3_table_offset(sva)];> +        l3e = 
> l3e_from_l4e(idle_pg_table[l4_table_offset(sva)],> +       
> l3_table_offset(sva));
> This macro doesn't exist yet in the tree. It would be good to spell out 
> the dependencies in the cover letter so this doesn't get merged before 
> the dependency is merged.
> 
> Reviewed-by: Julien Grall <jgrall@amazon.com>

Argh, I screwed the reply. Sorry for that. I will resend it.

-- 
Julien Grall

Re: [PATCH 1/6] x86_64/mm: map and unmap page tables in cleanup_frame_table

[Julien Grall]

(resending)

On 17/04/2020 10:52, Hongyan Xia wrote:
> From: Wei Liu <wei.liu2@citrix.com>
> 
> Also fix a weird indentation.
> 
> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
> ---
>   xen/arch/x86/x86_64/mm.c | 14 +++++++-------
>   1 file changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c
> index e85ef449f3..18210405f4 100644
> --- a/xen/arch/x86/x86_64/mm.c
> +++ b/xen/arch/x86/x86_64/mm.c
> @@ -737,8 +737,8 @@ static void cleanup_frame_table(struct mem_hotadd_info *info)
>   
>       while (sva < eva)
>       {
> -        l3e = l4e_to_l3e(idle_pg_table[l4_table_offset(sva)])[
> -          l3_table_offset(sva)];
> +        l3e = l3e_from_l4e(idle_pg_table[l4_table_offset(sva)],
> +                           l3_table_offset(sva));

This macro doesn't exist yet in the tree. It would be good to spell out 
the dependencies in the cover letter so this doesn't get merged before 
the dependency is merged.

Reviewed-by: Julien Grall <jgrall@amazon.com>

Cheers,

-- 
Julien Grall

Re: [PATCH 1/6] x86_64/mm: map and unmap page tables in cleanup_frame_table

[Hongyan Xia]

Hi Julien,

On Fri, 2020-04-24 at 09:59 +0100, Julien Grall wrote:
> (resending)
> 
> On 17/04/2020 10:52, Hongyan Xia wrote:
> > From: Wei Liu <wei.liu2@citrix.com>
> > 
> > Also fix a weird indentation.
> > 
> > Signed-off-by: Wei Liu <wei.liu2@citrix.com>
> > Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
> > ---
> >   xen/arch/x86/x86_64/mm.c | 14 +++++++-------
> >   1 file changed, 7 insertions(+), 7 deletions(-)
> > 
> > diff --git a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c
> > index e85ef449f3..18210405f4 100644
> > --- a/xen/arch/x86/x86_64/mm.c
> > +++ b/xen/arch/x86/x86_64/mm.c
> > @@ -737,8 +737,8 @@ static void cleanup_frame_table(struct
> > mem_hotadd_info *info)
> >   
> >       while (sva < eva)
> >       {
> > -        l3e = l4e_to_l3e(idle_pg_table[l4_table_offset(sva)])[
> > -          l3_table_offset(sva)];
> > +        l3e = l3e_from_l4e(idle_pg_table[l4_table_offset(sva)],
> > +                           l3_table_offset(sva));
> 
> This macro doesn't exist yet in the tree. It would be good to spell
> out 
> the dependencies in the cover letter so this doesn't get merged
> before 
> the dependency is merged.

I believe the introduction of the new macros has been merged in staging
as 6c8afe5aadb33761431b24157d99b25eac15fc7e.

> Reviewed-by: Julien Grall <jgrall@amazon.com>

Thanks!

Hongyan

Re: [PATCH 1/6] x86_64/mm: map and unmap page tables in cleanup_frame_table

[Julien Grall]

On 24/04/2020 10:21, Hongyan Xia wrote:
> Hi Julien,
> 
> On Fri, 2020-04-24 at 09:59 +0100, Julien Grall wrote:
>> (resending)
>>
>> On 17/04/2020 10:52, Hongyan Xia wrote:
>>> From: Wei Liu <wei.liu2@citrix.com>
>>>
>>> Also fix a weird indentation.
>>>
>>> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
>>> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
>>> ---
>>>    xen/arch/x86/x86_64/mm.c | 14 +++++++-------
>>>    1 file changed, 7 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c
>>> index e85ef449f3..18210405f4 100644
>>> --- a/xen/arch/x86/x86_64/mm.c
>>> +++ b/xen/arch/x86/x86_64/mm.c
>>> @@ -737,8 +737,8 @@ static void cleanup_frame_table(struct
>>> mem_hotadd_info *info)
>>>    
>>>        while (sva < eva)
>>>        {
>>> -        l3e = l4e_to_l3e(idle_pg_table[l4_table_offset(sva)])[
>>> -          l3_table_offset(sva)];
>>> +        l3e = l3e_from_l4e(idle_pg_table[l4_table_offset(sva)],
>>> +                           l3_table_offset(sva));
>>
>> This macro doesn't exist yet in the tree. It would be good to spell
>> out
>> the dependencies in the cover letter so this doesn't get merged
>> before
>> the dependency is merged.
> 
> I believe the introduction of the new macros has been merged in staging
> as 6c8afe5aadb33761431b24157d99b25eac15fc7e.

Hmmmm you are right. I must have been blind. Sorry for the noise.

Cheers,

-- 
Julien Grall

Re: [PATCH 1/6] x86_64/mm: map and unmap page tables in cleanup_frame_table

[Julien Grall]

On 17/04/2020 10:52, Hongyan Xia wrote:
> From: Wei Liu <wei.liu2@citrix.com>
> 
> Also fix a weird indentation.
> 
> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
> ---
>   xen/arch/x86/x86_64/mm.c | 14 +++++++-------
>   1 file changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c
> index e85ef449f3..18210405f4 100644
> --- a/xen/arch/x86/x86_64/mm.c
> +++ b/xen/arch/x86/x86_64/mm.c
> @@ -737,8 +737,8 @@ static void cleanup_frame_table(struct mem_hotadd_info *info)
>   
>       while (sva < eva)
>       {
> -        l3e = l4e_to_l3e(idle_pg_table[l4_table_offset(sva)])[
> -          l3_table_offset(sva)];
> +        l3e = l3e_from_l4e(idle_pg_table[l4_table_offset(sva)],
> +                           l3_table_offset(sva));
>           if ( !(l3e_get_flags(l3e) & _PAGE_PRESENT) ||
>                (l3e_get_flags(l3e) & _PAGE_PSE) )
>           {
> @@ -747,7 +747,7 @@ static void cleanup_frame_table(struct mem_hotadd_info *info)
>               continue;
>           }
>   
> -        l2e = l3e_to_l2e(l3e)[l2_table_offset(sva)];
> +        l2e = l2e_from_l3e(l3e, l2_table_offset(sva));
>           ASSERT(l2e_get_flags(l2e) & _PAGE_PRESENT);
>   
>           if ( (l2e_get_flags(l2e) & (_PAGE_PRESENT | _PAGE_PSE)) ==
> @@ -763,10 +763,10 @@ static void cleanup_frame_table(struct mem_hotadd_info *info)
>               continue;
>           }
>   
> -        ASSERT(l1e_get_flags(l2e_to_l1e(l2e)[l1_table_offset(sva)]) &
> -                _PAGE_PRESENT);
> -         sva = (sva & ~((1UL << PAGE_SHIFT) - 1)) +
> -                    (1UL << PAGE_SHIFT);
> +        ASSERT(l1e_get_flags(l1e_from_l2e(l2e, l1_table_offset(sva))) &
> +               _PAGE_PRESENT);
> +
> +        sva = (sva & ~((1UL << PAGE_SHIFT) - 1)) + (1UL << PAGE_SHIFT);

NIT: While you are modifying the indentation. Couldn't we use PAGE_MASK 
and PAGE_SIZE here?

Cheers,

-- 
Julien Grall

Re: [PATCH 1/6] x86_64/mm: map and unmap page tables in cleanup_frame_table

[Jan Beulich]

On 24.04.2020 11:02, Julien Grall wrote:
> On 17/04/2020 10:52, Hongyan Xia wrote:
>> @@ -763,10 +763,10 @@ static void cleanup_frame_table(struct mem_hotadd_info *info)
>>               continue;
>>           }
>>   -        ASSERT(l1e_get_flags(l2e_to_l1e(l2e)[l1_table_offset(sva)]) &
>> -                _PAGE_PRESENT);
>> -         sva = (sva & ~((1UL << PAGE_SHIFT) - 1)) +
>> -                    (1UL << PAGE_SHIFT);
>> +        ASSERT(l1e_get_flags(l1e_from_l2e(l2e, l1_table_offset(sva))) &
>> +               _PAGE_PRESENT);
>> +
>> +        sva = (sva & ~((1UL << PAGE_SHIFT) - 1)) + (1UL << PAGE_SHIFT);
> 
> NIT: While you are modifying the indentation. Couldn't we use PAGE_MASK and PAGE_SIZE here?

Oh, yes, this would be nice.

Jan

Re: [PATCH 1/6] x86_64/mm: map and unmap page tables in cleanup_frame_table

[Jan Beulich]

On 24.04.2020 11:02, Julien Grall wrote:
> On 17/04/2020 10:52, Hongyan Xia wrote:
>> @@ -763,10 +763,10 @@ static void cleanup_frame_table(struct mem_hotadd_info *info)
>>               continue;
>>           }
>>   -        ASSERT(l1e_get_flags(l2e_to_l1e(l2e)[l1_table_offset(sva)]) &
>> -                _PAGE_PRESENT);
>> -         sva = (sva & ~((1UL << PAGE_SHIFT) - 1)) +
>> -                    (1UL << PAGE_SHIFT);
>> +        ASSERT(l1e_get_flags(l1e_from_l2e(l2e, l1_table_offset(sva))) &
>> +               _PAGE_PRESENT);
>> +
>> +        sva = (sva & ~((1UL << PAGE_SHIFT) - 1)) + (1UL << PAGE_SHIFT);
> 
> NIT: While you are modifying the indentation. Couldn't we use PAGE_MASK and PAGE_SIZE here?

And with this (which I think can be done while committing)
Reviewed-by: Jan Beulich <jbeulich@suse.com>

Jan

[PATCH 2/6] x86_64/mm: map and unmap page tables in subarch_init_memory

[Hongyan Xia]

From: Wei Liu <wei.liu2@citrix.com>

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
---
 xen/arch/x86/x86_64/mm.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c
index 18210405f4..5714e5ba62 100644
--- a/xen/arch/x86/x86_64/mm.c
+++ b/xen/arch/x86/x86_64/mm.c
@@ -852,14 +852,14 @@ void __init subarch_init_memory(void)
           v += n << PAGE_SHIFT )
     {
         n = L2_PAGETABLE_ENTRIES * L1_PAGETABLE_ENTRIES;
-        l3e = l4e_to_l3e(idle_pg_table[l4_table_offset(v)])[
-            l3_table_offset(v)];
+        l3e = l3e_from_l4e(idle_pg_table[l4_table_offset(v)],
+                           l3_table_offset(v));
         if ( !(l3e_get_flags(l3e) & _PAGE_PRESENT) )
             continue;
         if ( !(l3e_get_flags(l3e) & _PAGE_PSE) )
         {
             n = L1_PAGETABLE_ENTRIES;
-            l2e = l3e_to_l2e(l3e)[l2_table_offset(v)];
+            l2e = l2e_from_l3e(l3e, l2_table_offset(v));
             if ( !(l2e_get_flags(l2e) & _PAGE_PRESENT) )
                 continue;
             m2p_start_mfn = l2e_get_pfn(l2e);
@@ -878,11 +878,11 @@ void __init subarch_init_memory(void)
           v != RDWR_COMPAT_MPT_VIRT_END;
           v += 1 << L2_PAGETABLE_SHIFT )
     {
-        l3e = l4e_to_l3e(idle_pg_table[l4_table_offset(v)])[
-            l3_table_offset(v)];
+        l3e = l3e_from_l4e(idle_pg_table[l4_table_offset(v)],
+                           l3_table_offset(v));
         if ( !(l3e_get_flags(l3e) & _PAGE_PRESENT) )
             continue;
-        l2e = l3e_to_l2e(l3e)[l2_table_offset(v)];
+        l2e = l2e_from_l3e(l3e, l2_table_offset(v));
         if ( !(l2e_get_flags(l2e) & _PAGE_PRESENT) )
             continue;
         m2p_start_mfn = l2e_get_pfn(l2e);
-- 
2.24.1.AMZN

Re: [PATCH 2/6] x86_64/mm: map and unmap page tables in subarch_init_memory

[Julien Grall]

Hi,

On 17/04/2020 10:52, Hongyan Xia wrote:
> From: Wei Liu <wei.liu2@citrix.com>
> 
> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>

Reviewed-by: Julien Grall <jgrall@amazon.com>

Cheers,

-- 
Julien Grall

Re: [PATCH 2/6] x86_64/mm: map and unmap page tables in subarch_init_memory

[Jan Beulich]

On 24.04.2020 11:04, Julien Grall wrote:
> On 17/04/2020 10:52, Hongyan Xia wrote:
>> From: Wei Liu <wei.liu2@citrix.com>
>>
>> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
>> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
> 
> Reviewed-by: Julien Grall <jgrall@amazon.com>

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

[PATCH 3/6] x86_64/mm: map and unmap page tables in subarch_memory_op

[Hongyan Xia]

From: Wei Liu <wei.liu2@citrix.com>

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
---
 xen/arch/x86/x86_64/mm.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c
index 5714e5ba62..6d52183559 100644
--- a/xen/arch/x86/x86_64/mm.c
+++ b/xen/arch/x86/x86_64/mm.c
@@ -932,13 +932,13 @@ long subarch_memory_op(unsigned long cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
               (v < (unsigned long)(machine_to_phys_mapping + max_page));
               i++, v += 1UL << L2_PAGETABLE_SHIFT )
         {
-            l3e = l4e_to_l3e(idle_pg_table[l4_table_offset(v)])[
-                l3_table_offset(v)];
+            l3e = l3e_from_l4e(idle_pg_table[l4_table_offset(v)],
+                               l3_table_offset(v));
             if ( !(l3e_get_flags(l3e) & _PAGE_PRESENT) )
                 mfn = last_mfn;
             else if ( !(l3e_get_flags(l3e) & _PAGE_PSE) )
             {
-                l2e = l3e_to_l2e(l3e)[l2_table_offset(v)];
+                l2e = l2e_from_l3e(l3e, l2_table_offset(v));
                 if ( l2e_get_flags(l2e) & _PAGE_PRESENT )
                     mfn = l2e_get_pfn(l2e);
                 else
-- 
2.24.1.AMZN

Re: [PATCH 3/6] x86_64/mm: map and unmap page tables in subarch_memory_op

[Julien Grall]

Hi Hongyan,

On 17/04/2020 10:52, Hongyan Xia wrote:
> From: Wei Liu <wei.liu2@citrix.com>
> 
> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>

Reviewed-by: Julien Grall <jgrall@amazon.com>

Cheers,

-- 
Julien Grall

Re: [PATCH 3/6] x86_64/mm: map and unmap page tables in subarch_memory_op

[Jan Beulich]

On 24.04.2020 11:06, Julien Grall wrote:
> On 17/04/2020 10:52, Hongyan Xia wrote:
>> From: Wei Liu <wei.liu2@citrix.com>
>>
>> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
>> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
> 
> Reviewed-by: Julien Grall <jgrall@amazon.com>

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

[PATCH 4/6] x86/smpboot: map and unmap page tables in cleanup_cpu_root_pgt

[Hongyan Xia]

From: Wei Liu <wei.liu2@citrix.com>

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
---
 xen/arch/x86/smpboot.c | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/xen/arch/x86/smpboot.c b/xen/arch/x86/smpboot.c
index 09264b02d1..275ce7661d 100644
--- a/xen/arch/x86/smpboot.c
+++ b/xen/arch/x86/smpboot.c
@@ -858,23 +858,27 @@ static void cleanup_cpu_root_pgt(unsigned int cpu)
           r < root_table_offset(HYPERVISOR_VIRT_END); ++r )
     {
         l3_pgentry_t *l3t;
+        mfn_t l3mfn;
         unsigned int i3;
 
         if ( !(root_get_flags(rpt[r]) & _PAGE_PRESENT) )
             continue;
 
-        l3t = l4e_to_l3e(rpt[r]);
+        l3mfn = l4e_get_mfn(rpt[r]);
+        l3t = map_domain_page(l3mfn);
 
         for ( i3 = 0; i3 < L3_PAGETABLE_ENTRIES; ++i3 )
         {
             l2_pgentry_t *l2t;
+            mfn_t l2mfn;
             unsigned int i2;
 
             if ( !(l3e_get_flags(l3t[i3]) & _PAGE_PRESENT) )
                 continue;
 
             ASSERT(!(l3e_get_flags(l3t[i3]) & _PAGE_PSE));
-            l2t = l3e_to_l2e(l3t[i3]);
+            l2mfn = l3e_get_mfn(l3t[i3]);
+            l2t = map_domain_page(l2mfn);
 
             for ( i2 = 0; i2 < L2_PAGETABLE_ENTRIES; ++i2 )
             {
@@ -882,13 +886,15 @@ static void cleanup_cpu_root_pgt(unsigned int cpu)
                     continue;
 
                 ASSERT(!(l2e_get_flags(l2t[i2]) & _PAGE_PSE));
-                free_xen_pagetable(l2e_to_l1e(l2t[i2]));
+                free_xen_pagetable_new(l2e_get_mfn(l2t[i2]));
             }
 
-            free_xen_pagetable(l2t);
+            unmap_domain_page(l2t);
+            free_xen_pagetable_new(l2mfn);
         }
 
-        free_xen_pagetable(l3t);
+        unmap_domain_page(l3t);
+        free_xen_pagetable_new(l3mfn);
     }
 
     free_xen_pagetable(rpt);
@@ -896,11 +902,14 @@ static void cleanup_cpu_root_pgt(unsigned int cpu)
     /* Also zap the stub mapping for this CPU. */
     if ( stub_linear )
     {
-        l3_pgentry_t *l3t = l4e_to_l3e(common_pgt);
-        l2_pgentry_t *l2t = l3e_to_l2e(l3t[l3_table_offset(stub_linear)]);
-        l1_pgentry_t *l1t = l2e_to_l1e(l2t[l2_table_offset(stub_linear)]);
+        l3_pgentry_t l3e = l3e_from_l4e(common_pgt,
+                                        l3_table_offset(stub_linear));
+        l2_pgentry_t l2e = l2e_from_l3e(l3e, l2_table_offset(stub_linear));
+        l1_pgentry_t *l1t = map_l1t_from_l2e(l2e);
 
         l1t[l1_table_offset(stub_linear)] = l1e_empty();
+
+        unmap_domain_page(l1t);
     }
 }
 
-- 
2.24.1.AMZN

Re: [PATCH 4/6] x86/smpboot: map and unmap page tables in cleanup_cpu_root_pgt

[Julien Grall]

Hi,

On 17/04/2020 10:52, Hongyan Xia wrote:
> From: Wei Liu <wei.liu2@citrix.com>
> 
> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>

Reviewed-by: Julien Grall <jgrall@amazon.com>

> ---
>   xen/arch/x86/smpboot.c | 25 +++++++++++++++++--------
>   1 file changed, 17 insertions(+), 8 deletions(-)
> 
> diff --git a/xen/arch/x86/smpboot.c b/xen/arch/x86/smpboot.c
> index 09264b02d1..275ce7661d 100644
> --- a/xen/arch/x86/smpboot.c
> +++ b/xen/arch/x86/smpboot.c
> @@ -858,23 +858,27 @@ static void cleanup_cpu_root_pgt(unsigned int cpu)
>             r < root_table_offset(HYPERVISOR_VIRT_END); ++r )
>       {
>           l3_pgentry_t *l3t;
> +        mfn_t l3mfn;
>           unsigned int i3;
>   
>           if ( !(root_get_flags(rpt[r]) & _PAGE_PRESENT) )
>               continue;
>   
> -        l3t = l4e_to_l3e(rpt[r]);
> +        l3mfn = l4e_get_mfn(rpt[r]);
> +        l3t = map_domain_page(l3mfn);
>   
>           for ( i3 = 0; i3 < L3_PAGETABLE_ENTRIES; ++i3 )
>           {
>               l2_pgentry_t *l2t;
> +            mfn_t l2mfn;
>               unsigned int i2;
>   
>               if ( !(l3e_get_flags(l3t[i3]) & _PAGE_PRESENT) )
>                   continue;
>   
>               ASSERT(!(l3e_get_flags(l3t[i3]) & _PAGE_PSE));
> -            l2t = l3e_to_l2e(l3t[i3]);
> +            l2mfn = l3e_get_mfn(l3t[i3]);
> +            l2t = map_domain_page(l2mfn);
>   
>               for ( i2 = 0; i2 < L2_PAGETABLE_ENTRIES; ++i2 )
>               {
> @@ -882,13 +886,15 @@ static void cleanup_cpu_root_pgt(unsigned int cpu)
>                       continue;
>   
>                   ASSERT(!(l2e_get_flags(l2t[i2]) & _PAGE_PSE));
> -                free_xen_pagetable(l2e_to_l1e(l2t[i2]));
> +                free_xen_pagetable_new(l2e_get_mfn(l2t[i2]));
>               }
>   
> -            free_xen_pagetable(l2t);
> +            unmap_domain_page(l2t);
> +            free_xen_pagetable_new(l2mfn);
>           }
>   
> -        free_xen_pagetable(l3t);
> +        unmap_domain_page(l3t);
> +        free_xen_pagetable_new(l3mfn);
>       }
>   
>       free_xen_pagetable(rpt);
> @@ -896,11 +902,14 @@ static void cleanup_cpu_root_pgt(unsigned int cpu)
>       /* Also zap the stub mapping for this CPU. */
>       if ( stub_linear )
>       {
> -        l3_pgentry_t *l3t = l4e_to_l3e(common_pgt);
> -        l2_pgentry_t *l2t = l3e_to_l2e(l3t[l3_table_offset(stub_linear)]);
> -        l1_pgentry_t *l1t = l2e_to_l1e(l2t[l2_table_offset(stub_linear)]);
> +        l3_pgentry_t l3e = l3e_from_l4e(common_pgt,
> +                                        l3_table_offset(stub_linear));
> +        l2_pgentry_t l2e = l2e_from_l3e(l3e, l2_table_offset(stub_linear));
> +        l1_pgentry_t *l1t = map_l1t_from_l2e(l2e);
>   
>           l1t[l1_table_offset(stub_linear)] = l1e_empty();
> +
> +        unmap_domain_page(l1t);
>       }
>   }
>   
> 

Cheers,

-- 
Julien Grall

Re: [PATCH 4/6] x86/smpboot: map and unmap page tables in cleanup_cpu_root_pgt

[Jan Beulich]

On 24.04.2020 11:13, Julien Grall wrote:
> On 17/04/2020 10:52, Hongyan Xia wrote:
>> From: Wei Liu <wei.liu2@citrix.com>
>>
>> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
>> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
> 
> Reviewed-by: Julien Grall <jgrall@amazon.com>

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

[PATCH 5/6] x86/pv: map and unmap page tables in mark_pv_pt_pages_rdonly

[Hongyan Xia]

From: Wei Liu <wei.liu2@citrix.com>

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
---
 xen/arch/x86/pv/dom0_build.c | 32 ++++++++++++++++++++------------
 1 file changed, 20 insertions(+), 12 deletions(-)

diff --git a/xen/arch/x86/pv/dom0_build.c b/xen/arch/x86/pv/dom0_build.c
index 5678da782d..28a939b68a 100644
--- a/xen/arch/x86/pv/dom0_build.c
+++ b/xen/arch/x86/pv/dom0_build.c
@@ -50,17 +50,17 @@ static __init void mark_pv_pt_pages_rdonly(struct domain *d,
     unsigned long count;
     struct page_info *page;
     l4_pgentry_t *pl4e;
-    l3_pgentry_t *pl3e;
-    l2_pgentry_t *pl2e;
-    l1_pgentry_t *pl1e;
+    l3_pgentry_t *pl3e, *l3t;
+    l2_pgentry_t *pl2e, *l2t;
+    l1_pgentry_t *pl1e, *l1t;
 
     pl4e = l4start + l4_table_offset(vpt_start);
-    pl3e = l4e_to_l3e(*pl4e);
-    pl3e += l3_table_offset(vpt_start);
-    pl2e = l3e_to_l2e(*pl3e);
-    pl2e += l2_table_offset(vpt_start);
-    pl1e = l2e_to_l1e(*pl2e);
-    pl1e += l1_table_offset(vpt_start);
+    l3t = map_l3t_from_l4e(*pl4e);
+    pl3e = l3t + l3_table_offset(vpt_start);
+    l2t = map_l2t_from_l3e(*pl3e);
+    pl2e = l2t + l2_table_offset(vpt_start);
+    l1t = map_l1t_from_l2e(*pl2e);
+    pl1e = l1t + l1_table_offset(vpt_start);
     for ( count = 0; count < nr_pt_pages; count++ )
     {
         l1e_remove_flags(*pl1e, _PAGE_RW);
@@ -85,12 +85,20 @@ static __init void mark_pv_pt_pages_rdonly(struct domain *d,
             if ( !((unsigned long)++pl2e & (PAGE_SIZE - 1)) )
             {
                 if ( !((unsigned long)++pl3e & (PAGE_SIZE - 1)) )
-                    pl3e = l4e_to_l3e(*++pl4e);
-                pl2e = l3e_to_l2e(*pl3e);
+                {
+                    unmap_domain_page(l3t);
+                    pl3e = l3t = map_l3t_from_l4e(*++pl4e);
+                }
+                unmap_domain_page(l2t);
+                pl2e = l2t = map_l2t_from_l3e(*pl3e);
             }
-            pl1e = l2e_to_l1e(*pl2e);
+            unmap_domain_page(l1t);
+            pl1e = l1t = map_l1t_from_l2e(*pl2e);
         }
     }
+    unmap_domain_page(l1t);
+    unmap_domain_page(l2t);
+    unmap_domain_page(l3t);
 }
 
 static __init void setup_pv_physmap(struct domain *d, unsigned long pgtbl_pfn,
-- 
2.24.1.AMZN

Re: [PATCH 5/6] x86/pv: map and unmap page tables in mark_pv_pt_pages_rdonly

[Julien Grall]

Hi,

On 17/04/2020 10:52, Hongyan Xia wrote:
> From: Wei Liu <wei.liu2@citrix.com>
> 
> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>

Reviewed-by: Julien Grall <jgrall@amazon.com>

Cheers,

-- 
Julien Grall

Re: [PATCH 5/6] x86/pv: map and unmap page tables in mark_pv_pt_pages_rdonly

[Jan Beulich]

On 17.04.2020 11:52, Hongyan Xia wrote:
> --- a/xen/arch/x86/pv/dom0_build.c
> +++ b/xen/arch/x86/pv/dom0_build.c
> @@ -50,17 +50,17 @@ static __init void mark_pv_pt_pages_rdonly(struct domain *d,
>      unsigned long count;
>      struct page_info *page;
>      l4_pgentry_t *pl4e;
> -    l3_pgentry_t *pl3e;
> -    l2_pgentry_t *pl2e;
> -    l1_pgentry_t *pl1e;
> +    l3_pgentry_t *pl3e, *l3t;
> +    l2_pgentry_t *pl2e, *l2t;
> +    l1_pgentry_t *pl1e, *l1t;

I don't quite see why the new local variables get introduced:
unmap_domain_page(), iirc, is quite fine with a non-page-
aligned argument.

Jan

Re: [PATCH 5/6] x86/pv: map and unmap page tables in mark_pv_pt_pages_rdonly

[Wei Liu]

On Tue, Apr 28, 2020 at 05:33:29PM +0200, Jan Beulich wrote:
> On 17.04.2020 11:52, Hongyan Xia wrote:
> > --- a/xen/arch/x86/pv/dom0_build.c
> > +++ b/xen/arch/x86/pv/dom0_build.c
> > @@ -50,17 +50,17 @@ static __init void mark_pv_pt_pages_rdonly(struct domain *d,
> >      unsigned long count;
> >      struct page_info *page;
> >      l4_pgentry_t *pl4e;
> > -    l3_pgentry_t *pl3e;
> > -    l2_pgentry_t *pl2e;
> > -    l1_pgentry_t *pl1e;
> > +    l3_pgentry_t *pl3e, *l3t;
> > +    l2_pgentry_t *pl2e, *l2t;
> > +    l1_pgentry_t *pl1e, *l1t;
> 
> I don't quite see why the new local variables get introduced:
> unmap_domain_page(), iirc, is quite fine with a non-page-
> aligned argument.

(Assuming this is actually written by me)

I wanted to make things abundantly clear: plXe points to an entry while
lXt points to the start of a page table.

In a long function the distinction could be helpful; in a short function
(like this one?) not so much.

Wei.

> 
> Jan

Re: [PATCH 5/6] x86/pv: map and unmap page tables in mark_pv_pt_pages_rdonly

[Hongyan Xia]

On Tue, 2020-04-28 at 17:33 +0200, Jan Beulich wrote:
> On 17.04.2020 11:52, Hongyan Xia wrote:
> > --- a/xen/arch/x86/pv/dom0_build.c
> > +++ b/xen/arch/x86/pv/dom0_build.c
> > @@ -50,17 +50,17 @@ static __init void
> > mark_pv_pt_pages_rdonly(struct domain *d,
> >      unsigned long count;
> >      struct page_info *page;
> >      l4_pgentry_t *pl4e;
> > -    l3_pgentry_t *pl3e;
> > -    l2_pgentry_t *pl2e;
> > -    l1_pgentry_t *pl1e;
> > +    l3_pgentry_t *pl3e, *l3t;
> > +    l2_pgentry_t *pl2e, *l2t;
> > +    l1_pgentry_t *pl1e, *l1t;
> 
> I don't quite see why the new local variables get introduced:
> unmap_domain_page(), iirc, is quite fine with a non-page-
> aligned argument.

You are right, although in this function, where plXe points to may not
be the page we want to unmap. When plXe becomes aligned and points to a
new page, we actually want to unmap the page before it increments to an
aligned value.

Hongyan

Re: [PATCH 5/6] x86/pv: map and unmap page tables in mark_pv_pt_pages_rdonly

[Hongyan Xia]

On Tue, 2020-04-28 at 16:55 +0100, Hongyan Xia wrote:
> On Tue, 2020-04-28 at 17:33 +0200, Jan Beulich wrote:
> > On 17.04.2020 11:52, Hongyan Xia wrote:
> > > --- a/xen/arch/x86/pv/dom0_build.c
> > > +++ b/xen/arch/x86/pv/dom0_build.c
> > > @@ -50,17 +50,17 @@ static __init void
> > > mark_pv_pt_pages_rdonly(struct domain *d,
> > >      unsigned long count;
> > >      struct page_info *page;
> > >      l4_pgentry_t *pl4e;
> > > -    l3_pgentry_t *pl3e;
> > > -    l2_pgentry_t *pl2e;
> > > -    l1_pgentry_t *pl1e;
> > > +    l3_pgentry_t *pl3e, *l3t;
> > > +    l2_pgentry_t *pl2e, *l2t;
> > > +    l1_pgentry_t *pl1e, *l1t;
> > 
> > I don't quite see why the new local variables get introduced:
> > unmap_domain_page(), iirc, is quite fine with a non-page-
> > aligned argument.
> 
> You are right, although in this function, where plXe points to may
> not
> be the page we want to unmap. When plXe becomes aligned and points to
> a
> new page, we actually want to unmap the page before it increments to
> an
> aligned value.

Hmm, we can just unmap(plXe - 1) if my logic is correct, and save 3
local variables.

Hongyan

Re: [PATCH 5/6] x86/pv: map and unmap page tables in mark_pv_pt_pages_rdonly

[Hongyan Xia]

On Tue, 2020-04-28 at 16:59 +0100, Hongyan Xia wrote:
> On Tue, 2020-04-28 at 16:55 +0100, Hongyan Xia wrote:
> > On Tue, 2020-04-28 at 17:33 +0200, Jan Beulich wrote:
> > > On 17.04.2020 11:52, Hongyan Xia wrote:
> > > > --- a/xen/arch/x86/pv/dom0_build.c
> > > > +++ b/xen/arch/x86/pv/dom0_build.c
> > > > @@ -50,17 +50,17 @@ static __init void
> > > > mark_pv_pt_pages_rdonly(struct domain *d,
> > > >      unsigned long count;
> > > >      struct page_info *page;
> > > >      l4_pgentry_t *pl4e;
> > > > -    l3_pgentry_t *pl3e;
> > > > -    l2_pgentry_t *pl2e;
> > > > -    l1_pgentry_t *pl1e;
> > > > +    l3_pgentry_t *pl3e, *l3t;
> > > > +    l2_pgentry_t *pl2e, *l2t;
> > > > +    l1_pgentry_t *pl1e, *l1t;
> > > 
> > > I don't quite see why the new local variables get introduced:
> > > unmap_domain_page(), iirc, is quite fine with a non-page-
> > > aligned argument.
> > 
> > You are right, although in this function, where plXe points to may
> > not
> > be the page we want to unmap. When plXe becomes aligned and points
> > to
> > a
> > new page, we actually want to unmap the page before it increments
> > to
> > an
> > aligned value.
> 
> Hmm, we can just unmap(plXe - 1) if my logic is correct, and save 3
> local variables.

Sorry for monologuing, but I still prefer separating plXe and lXt
because it makes it clear what we are unmapping. Unmapping plXe - 1 is
a bit hackish.

But if people do not have a problem with plXe - 1, I will post a new
revision for that.

Hongyan

Re: [PATCH 5/6] x86/pv: map and unmap page tables in mark_pv_pt_pages_rdonly

[Jan Beulich]

On 29.04.2020 11:26, Hongyan Xia wrote:
> But if people do not have a problem with plXe - 1, I will post a new
> revision for that.

I'd prefer that; I could live with the current version, but I'm
not in favor of it.

Jan

Re: [PATCH 5/6] x86/pv: map and unmap page tables in mark_pv_pt_pages_rdonly

[Hongyan Xia]

(Looks like other patches in this series have been merged. Replying to
this one only.)

From: Wei Liu <wei.liu2@citrix.com>
Date: Tue, 5 Feb 2019 16:32:54 +0000
Subject: [PATCH] x86/pv: map and unmap page tables in
mark_pv_pt_pages_rdonly

Also, clean up the initialisation of plXe.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
---
 xen/arch/x86/pv/dom0_build.c | 32 +++++++++++++++++---------------
 1 file changed, 17 insertions(+), 15 deletions(-)

diff --git a/xen/arch/x86/pv/dom0_build.c
b/xen/arch/x86/pv/dom0_build.c
index abfbe5f436..3522eb0114 100644
--- a/xen/arch/x86/pv/dom0_build.c
+++ b/xen/arch/x86/pv/dom0_build.c
@@ -49,18 +49,11 @@ static __init void mark_pv_pt_pages_rdonly(struct
domain *d,
 {
     unsigned long count;
     struct page_info *page;
-    l4_pgentry_t *pl4e;
-    l3_pgentry_t *pl3e;
-    l2_pgentry_t *pl2e;
-    l1_pgentry_t *pl1e;
-
-    pl4e = l4start + l4_table_offset(vpt_start);
-    pl3e = l4e_to_l3e(*pl4e);
-    pl3e += l3_table_offset(vpt_start);
-    pl2e = l3e_to_l2e(*pl3e);
-    pl2e += l2_table_offset(vpt_start);
-    pl1e = l2e_to_l1e(*pl2e);
-    pl1e += l1_table_offset(vpt_start);
+    l4_pgentry_t *pl4e = l4start + l4_table_offset(vpt_start);
+    l3_pgentry_t *pl3e = map_l3t_from_l4e(*pl4e) +
l3_table_offset(vpt_start);
+    l2_pgentry_t *pl2e = map_l2t_from_l3e(*pl3e) +
l2_table_offset(vpt_start);
+    l1_pgentry_t *pl1e = map_l1t_from_l2e(*pl2e) +
l1_table_offset(vpt_start);
+
     for ( count = 0; count < nr_pt_pages; count++ )
     {
         l1e_remove_flags(*pl1e, _PAGE_RW);
@@ -85,12 +78,21 @@ static __init void mark_pv_pt_pages_rdonly(struct
domain *d,
             if ( !((unsigned long)++pl2e & (PAGE_SIZE - 1)) )
             {
                 if ( !((unsigned long)++pl3e & (PAGE_SIZE - 1)) )
-                    pl3e = l4e_to_l3e(*++pl4e);
-                pl2e = l3e_to_l2e(*pl3e);
+                {
+                    /* Need to unmap the page before the increment. */
+                    unmap_domain_page(pl3e - 1);
+                    pl3e = map_l3t_from_l4e(*++pl4e);
+                }
+                unmap_domain_page(pl2e - 1);
+                pl2e = map_l2t_from_l3e(*pl3e);
             }
-            pl1e = l2e_to_l1e(*pl2e);
+            unmap_domain_page(pl1e - 1);
+            pl1e = map_l1t_from_l2e(*pl2e);
         }
     }
+    unmap_domain_page(pl1e);
+    unmap_domain_page(pl2e);
+    unmap_domain_page(pl3e);
 }
 
 static __init void setup_pv_physmap(struct domain *d, unsigned long
pgtbl_pfn,
-- 
2.24.1.AMZN

Re: [PATCH 5/6] x86/pv: map and unmap page tables in mark_pv_pt_pages_rdonly

[Jan Beulich]

On 29.04.2020 14:29, Hongyan Xia wrote:
> (Looks like other patches in this series have been merged. Replying to
> this one only.)

Please send as a proper patch, this one came through ...

> From: Wei Liu <wei.liu2@citrix.com>
> Date: Tue, 5 Feb 2019 16:32:54 +0000
> Subject: [PATCH] x86/pv: map and unmap page tables in
> mark_pv_pt_pages_rdonly
> 
> Also, clean up the initialisation of plXe.
> 
> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
> Reviewed-by: Julien Grall <jgrall@amazon.com>
> ---
>  xen/arch/x86/pv/dom0_build.c | 32 +++++++++++++++++---------------
>  1 file changed, 17 insertions(+), 15 deletions(-)
> 
> diff --git a/xen/arch/x86/pv/dom0_build.c
> b/xen/arch/x86/pv/dom0_build.c
> index abfbe5f436..3522eb0114 100644
> --- a/xen/arch/x86/pv/dom0_build.c
> +++ b/xen/arch/x86/pv/dom0_build.c
> @@ -49,18 +49,11 @@ static __init void mark_pv_pt_pages_rdonly(struct
> domain *d,
>  {
>      unsigned long count;
>      struct page_info *page;
> -    l4_pgentry_t *pl4e;
> -    l3_pgentry_t *pl3e;
> -    l2_pgentry_t *pl2e;
> -    l1_pgentry_t *pl1e;
> -
> -    pl4e = l4start + l4_table_offset(vpt_start);
> -    pl3e = l4e_to_l3e(*pl4e);
> -    pl3e += l3_table_offset(vpt_start);
> -    pl2e = l3e_to_l2e(*pl3e);
> -    pl2e += l2_table_offset(vpt_start);
> -    pl1e = l2e_to_l1e(*pl2e);
> -    pl1e += l1_table_offset(vpt_start);
> +    l4_pgentry_t *pl4e = l4start + l4_table_offset(vpt_start);
> +    l3_pgentry_t *pl3e = map_l3t_from_l4e(*pl4e) +
> l3_table_offset(vpt_start);
> +    l2_pgentry_t *pl2e = map_l2t_from_l3e(*pl3e) +
> l2_table_offset(vpt_start);
> +    l1_pgentry_t *pl1e = map_l1t_from_l2e(*pl2e) +
> l1_table_offset(vpt_start);

... mangled anyway. I also think with the change made you need to
drop the R-b.

Jan

[PATCH 6/6] x86/pv: map and unmap page table in dom0_construct_pv

[Hongyan Xia]

From: Wei Liu <wei.liu2@citrix.com>

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
---
 xen/arch/x86/pv/dom0_build.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/xen/arch/x86/pv/dom0_build.c b/xen/arch/x86/pv/dom0_build.c
index 28a939b68a..a03f0501ab 100644
--- a/xen/arch/x86/pv/dom0_build.c
+++ b/xen/arch/x86/pv/dom0_build.c
@@ -677,6 +677,8 @@ int __init dom0_construct_pv(struct domain *d,
 
     if ( is_pv_32bit_domain(d) )
     {
+        l2_pgentry_t *l2t;
+
         /* Ensure the first four L3 entries are all populated. */
         for ( i = 0, l3tab = l3start; i < 4; ++i, ++l3tab )
         {
@@ -691,7 +693,9 @@ int __init dom0_construct_pv(struct domain *d,
                 l3e_get_page(*l3tab)->u.inuse.type_info |= PGT_pae_xen_l2;
         }
 
-        init_xen_pae_l2_slots(l3e_to_l2e(l3start[3]), d);
+        l2t = map_l2t_from_l3e(l3start[3]);
+        init_xen_pae_l2_slots(l2t, d);
+        unmap_domain_page(l2t);
     }
 
     /* Pages that are part of page tables must be read only. */
-- 
2.24.1.AMZN

Re: [PATCH 6/6] x86/pv: map and unmap page table in dom0_construct_pv

[Julien Grall]

Hi,

On 17/04/2020 10:52, Hongyan Xia wrote:
> From: Wei Liu <wei.liu2@citrix.com>
> 
> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>

Reviewed-by: Julien Grall <jgrall@amazon.com>

Cheers,

-- 
Julien Grall

Re: [PATCH 6/6] x86/pv: map and unmap page table in dom0_construct_pv

[Jan Beulich]

On 24.04.2020 11:18, Julien Grall wrote:
> On 17/04/2020 10:52, Hongyan Xia wrote:
>> From: Wei Liu <wei.liu2@citrix.com>
>>
>> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
>> Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
> 
> Reviewed-by: Julien Grall <jgrall@amazon.com>

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

Re: [PATCH 0/6] convert more Xen page table code to the new API

[Hongyan Xia]

A gentle ping.

On Fri, 2020-04-17 at 10:52 +0100, Hongyan Xia wrote:
> From: Hongyan Xia <hongyxia@amazon.com>
> 
> Basically just rewriting functions using the new API to map and unmap
> PTEs. Each patch is independent.
> 
> Apart from mapping and unmapping page tables, no other functional
> change
> intended.
> 
> Wei Liu (6):
>   x86_64/mm: map and unmap page tables in cleanup_frame_table
>   x86_64/mm: map and unmap page tables in subarch_init_memory
>   x86_64/mm: map and unmap page tables in subarch_memory_op
>   x86/smpboot: map and unmap page tables in cleanup_cpu_root_pgt
>   x86/pv: map and unmap page tables in mark_pv_pt_pages_rdonly
>   x86/pv: map and unmap page table in dom0_construct_pv
> 
>  xen/arch/x86/pv/dom0_build.c | 38 ++++++++++++++++++++++++--------
> ----
>  xen/arch/x86/smpboot.c       | 25 ++++++++++++++++--------
>  xen/arch/x86/x86_64/mm.c     | 32 +++++++++++++++---------------
>  3 files changed, 58 insertions(+), 37 deletions(-)
>