Re: [Qemu-devel] [PATCH] kvmvapic: align start address as well as size

2012-03-15 Thread Anthony Liguori

On 03/15/2012 04:55 AM, Avi Kivity wrote:

On 03/14/2012 10:33 PM, Anthony Liguori wrote:

On 03/06/2012 09:50 AM, Avi Kivity wrote:

The kvmvapic code remaps a section of ROM as RAM to allow the guest to
maintain state there.  It is careful to align the section size to a page
boundary, to avoid creating subpages, but neglects to do the same for
the start address.  These leads to an assert later on when the memory
core tries to create a page which is half RAM and half ROM.

Fix by aligning the start address to a page boundary.

This can be triggered by running qemu-system-x86_64 -enable-kvm -vga
none.

Signed-off-by: Avi Kivity


Tested-by: Anthony Liguori

Are you going to do a PULL request or do you want me to apply directly?


I forgot all about it, sorry.


No worries.  I actually caught the bug in the original pull request but do to a 
bug in qemu-test, when I tried to bisect, things got weird and I mistakenly 
thought the real problem had been introduced earlier.


Regards,

Anthony Liguori








Re: [Qemu-devel] [PATCH] kvmvapic: align start address as well as size

2012-03-15 Thread Avi Kivity
On 03/14/2012 10:33 PM, Anthony Liguori wrote:
> On 03/06/2012 09:50 AM, Avi Kivity wrote:
>> The kvmvapic code remaps a section of ROM as RAM to allow the guest to
>> maintain state there.  It is careful to align the section size to a page
>> boundary, to avoid creating subpages, but neglects to do the same for
>> the start address.  These leads to an assert later on when the memory
>> core tries to create a page which is half RAM and half ROM.
>>
>> Fix by aligning the start address to a page boundary.
>>
>> This can be triggered by running qemu-system-x86_64 -enable-kvm -vga
>> none.
>>
>> Signed-off-by: Avi Kivity
>
> Tested-by: Anthony Liguori 
>
> Are you going to do a PULL request or do you want me to apply directly?

I forgot all about it, sorry.

-- 
error compiling committee.c: too many arguments to function




Re: [Qemu-devel] [PATCH] kvmvapic: align start address as well as size

2012-03-14 Thread Anthony Liguori

On 03/06/2012 09:50 AM, Avi Kivity wrote:

The kvmvapic code remaps a section of ROM as RAM to allow the guest to
maintain state there.  It is careful to align the section size to a page
boundary, to avoid creating subpages, but neglects to do the same for
the start address.  These leads to an assert later on when the memory
core tries to create a page which is half RAM and half ROM.

Fix by aligning the start address to a page boundary.

This can be triggered by running qemu-system-x86_64 -enable-kvm -vga none.

Signed-off-by: Avi Kivity


Applied.  Thanks.

Regards,

Anthony Liguori


---
  hw/kvmvapic.c |4 +++-
  1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/hw/kvmvapic.c b/hw/kvmvapic.c
index 36ccfbc..e8bfeec 100644
--- a/hw/kvmvapic.c
+++ b/hw/kvmvapic.c
@@ -578,8 +578,10 @@ static void vapic_map_rom_writable(VAPICROMState *s)
  rom_size = ram[rom_paddr + 2] * ROM_BLOCK_SIZE;
  s->rom_size = rom_size;

-/* We need to round up to avoid creating subpages
+/* We need to round to avoid creating subpages
   * from which we cannot run code. */
+rom_size += rom_paddr&  ~TARGET_PAGE_MASK;
+rom_paddr&= TARGET_PAGE_MASK;
  rom_size = TARGET_PAGE_ALIGN(rom_size);

  memory_region_init_alias(&s->rom, "kvmvapic-rom", section.mr, rom_paddr,





Re: [Qemu-devel] [PATCH] kvmvapic: align start address as well as size

2012-03-14 Thread Anthony Liguori

On 03/06/2012 09:50 AM, Avi Kivity wrote:

The kvmvapic code remaps a section of ROM as RAM to allow the guest to
maintain state there.  It is careful to align the section size to a page
boundary, to avoid creating subpages, but neglects to do the same for
the start address.  These leads to an assert later on when the memory
core tries to create a page which is half RAM and half ROM.

Fix by aligning the start address to a page boundary.

This can be triggered by running qemu-system-x86_64 -enable-kvm -vga none.

Signed-off-by: Avi Kivity


Tested-by: Anthony Liguori 

Are you going to do a PULL request or do you want me to apply directly?

Regards,

Anthony Liguori


---
  hw/kvmvapic.c |4 +++-
  1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/hw/kvmvapic.c b/hw/kvmvapic.c
index 36ccfbc..e8bfeec 100644
--- a/hw/kvmvapic.c
+++ b/hw/kvmvapic.c
@@ -578,8 +578,10 @@ static void vapic_map_rom_writable(VAPICROMState *s)
  rom_size = ram[rom_paddr + 2] * ROM_BLOCK_SIZE;
  s->rom_size = rom_size;

-/* We need to round up to avoid creating subpages
+/* We need to round to avoid creating subpages
   * from which we cannot run code. */
+rom_size += rom_paddr&  ~TARGET_PAGE_MASK;
+rom_paddr&= TARGET_PAGE_MASK;
  rom_size = TARGET_PAGE_ALIGN(rom_size);

  memory_region_init_alias(&s->rom, "kvmvapic-rom", section.mr, rom_paddr,





Re: [Qemu-devel] [PATCH] kvmvapic: align start address as well as size

2012-03-06 Thread Jan Kiszka
On 2012-03-06 16:50, Avi Kivity wrote:
> The kvmvapic code remaps a section of ROM as RAM to allow the guest to
> maintain state there.  It is careful to align the section size to a page
> boundary, to avoid creating subpages, but neglects to do the same for
> the start address.  These leads to an assert later on when the memory
> core tries to create a page which is half RAM and half ROM.
> 
> Fix by aligning the start address to a page boundary.
> 
> This can be triggered by running qemu-system-x86_64 -enable-kvm -vga none.
> 
> Signed-off-by: Avi Kivity 
> ---
>  hw/kvmvapic.c |4 +++-
>  1 files changed, 3 insertions(+), 1 deletions(-)
> 
> diff --git a/hw/kvmvapic.c b/hw/kvmvapic.c
> index 36ccfbc..e8bfeec 100644
> --- a/hw/kvmvapic.c
> +++ b/hw/kvmvapic.c
> @@ -578,8 +578,10 @@ static void vapic_map_rom_writable(VAPICROMState *s)
>  rom_size = ram[rom_paddr + 2] * ROM_BLOCK_SIZE;
>  s->rom_size = rom_size;
>  
> -/* We need to round up to avoid creating subpages
> +/* We need to round to avoid creating subpages
>   * from which we cannot run code. */
> +rom_size += rom_paddr & ~TARGET_PAGE_MASK;
> +rom_paddr &= TARGET_PAGE_MASK;
>  rom_size = TARGET_PAGE_ALIGN(rom_size);
>  
>  memory_region_init_alias(&s->rom, "kvmvapic-rom", section.mr, rom_paddr,

Reviewed-by: Jan Kiszka 

-- 
Siemens AG, Corporate Technology, CT T DE IT 1
Corporate Competence Center Embedded Linux



[Qemu-devel] [PATCH] kvmvapic: align start address as well as size

2012-03-06 Thread Avi Kivity
The kvmvapic code remaps a section of ROM as RAM to allow the guest to
maintain state there.  It is careful to align the section size to a page
boundary, to avoid creating subpages, but neglects to do the same for
the start address.  These leads to an assert later on when the memory
core tries to create a page which is half RAM and half ROM.

Fix by aligning the start address to a page boundary.

This can be triggered by running qemu-system-x86_64 -enable-kvm -vga none.

Signed-off-by: Avi Kivity 
---
 hw/kvmvapic.c |4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/hw/kvmvapic.c b/hw/kvmvapic.c
index 36ccfbc..e8bfeec 100644
--- a/hw/kvmvapic.c
+++ b/hw/kvmvapic.c
@@ -578,8 +578,10 @@ static void vapic_map_rom_writable(VAPICROMState *s)
 rom_size = ram[rom_paddr + 2] * ROM_BLOCK_SIZE;
 s->rom_size = rom_size;
 
-/* We need to round up to avoid creating subpages
+/* We need to round to avoid creating subpages
  * from which we cannot run code. */
+rom_size += rom_paddr & ~TARGET_PAGE_MASK;
+rom_paddr &= TARGET_PAGE_MASK;
 rom_size = TARGET_PAGE_ALIGN(rom_size);
 
 memory_region_init_alias(&s->rom, "kvmvapic-rom", section.mr, rom_paddr,
-- 
1.7.9