Patchwork fix bits 39:32 of the final physical address when using 4M page

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Submitter Wen Congyang
Date Dec. 22, 2012, 7:13 a.m.
Message ID <50D55DB2.6080601@cn.fujitsu.com>
Download mbox | patch
Permalink /patch/207923/
State New
Headers show

Comments

Wen Congyang - Dec. 22, 2012, 7:13 a.m.
((pde & 0x1fe000) << 19) is the bits 39:32 of the final physical address, and
we shouldn't use unit32_t to calculate it. Convert the type to hwaddr to fix
this problem.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>

---
 target-i386/arch_memory_mapping.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)
Markus Armbruster - Jan. 7, 2013, 12:06 p.m.
Wen Congyang <wency@cn.fujitsu.com> writes:

> ((pde & 0x1fe000) << 19) is the bits 39:32 of the final physical address, and
> we shouldn't use unit32_t to calculate it. Convert the type to hwaddr to fix
> this problem.

Spotted by Coverity.

> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
>
> ---
>  target-i386/arch_memory_mapping.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/target-i386/arch_memory_mapping.c b/target-i386/arch_memory_mapping.c
> index c6c7874..844893f 100644
> --- a/target-i386/arch_memory_mapping.c
> +++ b/target-i386/arch_memory_mapping.c
> @@ -115,7 +115,7 @@ static void walk_pde2(MemoryMappingList *list,
>                        hwaddr pde_start_addr, int32_t a20_mask,
>                        bool pse)
>  {
> -    hwaddr pde_addr, pte_start_addr, start_paddr;
> +    hwaddr pde_addr, pte_start_addr, start_paddr, high_paddr;
>      uint32_t pde;
>      target_ulong line_addr, start_vaddr;
>      int i;
> @@ -130,8 +130,13 @@ static void walk_pde2(MemoryMappingList *list,
>  
>          line_addr = (((unsigned int)i & 0x3ff) << 22);
>          if ((pde & PG_PSE_MASK) && pse) {
> -            /* 4 MB page */
> -            start_paddr = (pde & ~0x3fffff) | ((pde & 0x1fe000) << 19);
> +            /*
> +             * 4 MB page:
> +             * bits 39:32 are bits 20:13 of the PDE
> +             * bit3 31:22 are bits 31:22 of the PDE
> +             */
> +            high_paddr = ((hwaddr)(pde & 0x1fe000) << 19);
> +            start_paddr = (pde & ~0x3fffff) | high_paddr;
>              if (cpu_physical_memory_is_io(start_paddr)) {
>                  /* I/O region */
>                  continue;

Extra points for extending the comment.

Reviewed-by: Markus Armbruster <armbru@redhat.com>
Andreas Färber - Jan. 7, 2013, 1:10 p.m.
Am 07.01.2013 13:06, schrieb Markus Armbruster:
> Wen Congyang <wency@cn.fujitsu.com> writes:
> 
>> ((pde & 0x1fe000) << 19) is the bits 39:32 of the final physical address, and
>> we shouldn't use unit32_t to calculate it. Convert the type to hwaddr to fix
>> this problem.
> 
> Spotted by Coverity.
> 
>> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
>>
>> ---
>>  target-i386/arch_memory_mapping.c | 11 ++++++++---
>>  1 file changed, 8 insertions(+), 3 deletions(-)
>>
>> diff --git a/target-i386/arch_memory_mapping.c b/target-i386/arch_memory_mapping.c
>> index c6c7874..844893f 100644
>> --- a/target-i386/arch_memory_mapping.c
>> +++ b/target-i386/arch_memory_mapping.c
>> @@ -115,7 +115,7 @@ static void walk_pde2(MemoryMappingList *list,
>>                        hwaddr pde_start_addr, int32_t a20_mask,
>>                        bool pse)
>>  {
>> -    hwaddr pde_addr, pte_start_addr, start_paddr;
>> +    hwaddr pde_addr, pte_start_addr, start_paddr, high_paddr;
>>      uint32_t pde;
>>      target_ulong line_addr, start_vaddr;
>>      int i;
>> @@ -130,8 +130,13 @@ static void walk_pde2(MemoryMappingList *list,
>>  
>>          line_addr = (((unsigned int)i & 0x3ff) << 22);
>>          if ((pde & PG_PSE_MASK) && pse) {
>> -            /* 4 MB page */
>> -            start_paddr = (pde & ~0x3fffff) | ((pde & 0x1fe000) << 19);
>> +            /*
>> +             * 4 MB page:
>> +             * bits 39:32 are bits 20:13 of the PDE
>> +             * bit3 31:22 are bits 31:22 of the PDE
>> +             */
>> +            high_paddr = ((hwaddr)(pde & 0x1fe000) << 19);
>> +            start_paddr = (pde & ~0x3fffff) | high_paddr;
>>              if (cpu_physical_memory_is_io(start_paddr)) {
>>                  /* I/O region */
>>                  continue;
> 
> Extra points for extending the comment.

...and a "target-i386: " prefix in the subject would be appreciated,
since it does not seem to fix a general issue.

Andreas

> 
> Reviewed-by: Markus Armbruster <armbru@redhat.com>
>
Luiz Capitulino - Jan. 7, 2013, 1:40 p.m.
On Mon, 07 Jan 2013 14:10:46 +0100
Andreas Färber <afaerber@suse.de> wrote:

> Am 07.01.2013 13:06, schrieb Markus Armbruster:
> > Wen Congyang <wency@cn.fujitsu.com> writes:
> > 
> >> ((pde & 0x1fe000) << 19) is the bits 39:32 of the final physical address, and
> >> we shouldn't use unit32_t to calculate it. Convert the type to hwaddr to fix
> >> this problem.
> > 
> > Spotted by Coverity.
> > 
> >> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
> >>
> >> ---
> >>  target-i386/arch_memory_mapping.c | 11 ++++++++---
> >>  1 file changed, 8 insertions(+), 3 deletions(-)
> >>
> >> diff --git a/target-i386/arch_memory_mapping.c b/target-i386/arch_memory_mapping.c
> >> index c6c7874..844893f 100644
> >> --- a/target-i386/arch_memory_mapping.c
> >> +++ b/target-i386/arch_memory_mapping.c
> >> @@ -115,7 +115,7 @@ static void walk_pde2(MemoryMappingList *list,
> >>                        hwaddr pde_start_addr, int32_t a20_mask,
> >>                        bool pse)
> >>  {
> >> -    hwaddr pde_addr, pte_start_addr, start_paddr;
> >> +    hwaddr pde_addr, pte_start_addr, start_paddr, high_paddr;
> >>      uint32_t pde;
> >>      target_ulong line_addr, start_vaddr;
> >>      int i;
> >> @@ -130,8 +130,13 @@ static void walk_pde2(MemoryMappingList *list,
> >>  
> >>          line_addr = (((unsigned int)i & 0x3ff) << 22);
> >>          if ((pde & PG_PSE_MASK) && pse) {
> >> -            /* 4 MB page */
> >> -            start_paddr = (pde & ~0x3fffff) | ((pde & 0x1fe000) << 19);
> >> +            /*
> >> +             * 4 MB page:
> >> +             * bits 39:32 are bits 20:13 of the PDE
> >> +             * bit3 31:22 are bits 31:22 of the PDE
> >> +             */
> >> +            high_paddr = ((hwaddr)(pde & 0x1fe000) << 19);
> >> +            start_paddr = (pde & ~0x3fffff) | high_paddr;
> >>              if (cpu_physical_memory_is_io(start_paddr)) {
> >>                  /* I/O region */
> >>                  continue;
> > 
> > Extra points for extending the comment.
> 
> ...and a "target-i386: " prefix in the subject would be appreciated,
> since it does not seem to fix a general issue.

I can do that myself when I apply the patch (which will take a little bit,
as I'm just back from vacation).

> 
> Andreas
> 
> > 
> > Reviewed-by: Markus Armbruster <armbru@redhat.com>
> > 
> 
>
Luiz Capitulino - Jan. 9, 2013, 11:47 a.m.
On Sat, 22 Dec 2012 15:13:54 +0800
Wen Congyang <wency@cn.fujitsu.com> wrote:

> ((pde & 0x1fe000) << 19) is the bits 39:32 of the final physical address, and
> we shouldn't use unit32_t to calculate it. Convert the type to hwaddr to fix
> this problem.
> 
> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>

Applied to the qmp branch, thanks.

> 
> ---
>  target-i386/arch_memory_mapping.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/target-i386/arch_memory_mapping.c b/target-i386/arch_memory_mapping.c
> index c6c7874..844893f 100644
> --- a/target-i386/arch_memory_mapping.c
> +++ b/target-i386/arch_memory_mapping.c
> @@ -115,7 +115,7 @@ static void walk_pde2(MemoryMappingList *list,
>                        hwaddr pde_start_addr, int32_t a20_mask,
>                        bool pse)
>  {
> -    hwaddr pde_addr, pte_start_addr, start_paddr;
> +    hwaddr pde_addr, pte_start_addr, start_paddr, high_paddr;
>      uint32_t pde;
>      target_ulong line_addr, start_vaddr;
>      int i;
> @@ -130,8 +130,13 @@ static void walk_pde2(MemoryMappingList *list,
>  
>          line_addr = (((unsigned int)i & 0x3ff) << 22);
>          if ((pde & PG_PSE_MASK) && pse) {
> -            /* 4 MB page */
> -            start_paddr = (pde & ~0x3fffff) | ((pde & 0x1fe000) << 19);
> +            /*
> +             * 4 MB page:
> +             * bits 39:32 are bits 20:13 of the PDE
> +             * bit3 31:22 are bits 31:22 of the PDE
> +             */
> +            high_paddr = ((hwaddr)(pde & 0x1fe000) << 19);
> +            start_paddr = (pde & ~0x3fffff) | high_paddr;
>              if (cpu_physical_memory_is_io(start_paddr)) {
>                  /* I/O region */
>                  continue;

Patch

diff --git a/target-i386/arch_memory_mapping.c b/target-i386/arch_memory_mapping.c
index c6c7874..844893f 100644
--- a/target-i386/arch_memory_mapping.c
+++ b/target-i386/arch_memory_mapping.c
@@ -115,7 +115,7 @@  static void walk_pde2(MemoryMappingList *list,
                       hwaddr pde_start_addr, int32_t a20_mask,
                       bool pse)
 {
-    hwaddr pde_addr, pte_start_addr, start_paddr;
+    hwaddr pde_addr, pte_start_addr, start_paddr, high_paddr;
     uint32_t pde;
     target_ulong line_addr, start_vaddr;
     int i;
@@ -130,8 +130,13 @@  static void walk_pde2(MemoryMappingList *list,
 
         line_addr = (((unsigned int)i & 0x3ff) << 22);
         if ((pde & PG_PSE_MASK) && pse) {
-            /* 4 MB page */
-            start_paddr = (pde & ~0x3fffff) | ((pde & 0x1fe000) << 19);
+            /*
+             * 4 MB page:
+             * bits 39:32 are bits 20:13 of the PDE
+             * bit3 31:22 are bits 31:22 of the PDE
+             */
+            high_paddr = ((hwaddr)(pde & 0x1fe000) << 19);
+            start_paddr = (pde & ~0x3fffff) | high_paddr;
             if (cpu_physical_memory_is_io(start_paddr)) {
                 /* I/O region */
                 continue;