[PATCH 0/4] X86: Alias isa-bios area and clean up

Bernhard Beschow posted 4 patches 1 week, 6 days ago
Patches applied successfully (tree, apply log)
git fetch https://github.com/patchew-project/qemu tags/patchew/20240422200625.2768-1-shentey@gmail.com
Maintainers: "Michael S. Tsirkin" <mst@redhat.com>, Marcel Apfelbaum <marcel.apfelbaum@gmail.com>, Paolo Bonzini <pbonzini@redhat.com>, Richard Henderson <richard.henderson@linaro.org>, Eduardo Habkost <eduardo@habkost.net>
include/hw/i386/x86.h |  2 ++
hw/i386/pc_sysfw.c    | 38 ++++----------------------------------
hw/i386/x86.c         | 35 +++++++++++++++++++----------------
3 files changed, 25 insertions(+), 50 deletions(-)
[PATCH 0/4] X86: Alias isa-bios area and clean up
Posted by Bernhard Beschow 1 week, 6 days ago
This series changes the "isa-bios" MemoryRegion to be an alias rather than a
copy in the pflash case. This fixes issuing pflash commands in the isa-bios
region which matches real hardware and which some real-world legacy bioses I'm
running rely on. Furthermore, aliasing in the isa-bios area is already the
current behavior in the bios (a.k.a. ROM) case, so this series consolidates
behavior.

The consolidateion results in duplicate code which is resolved in the second
half (patches 3 and 4) in this series.

Question: AFAIU, patch 2 changes the behavior for SEV-enabled guests since the
isa-bios area is now encrypted. Does this need compat machinery or is it a
bugfix?

Testing done:
* `make check` with qemu-system-x86_64 (QEMU 8.2.2) installed. All tests
  including migration tests pass.
* `make check-avocado`

Best regards,
Bernhard

Bernhard Beschow (4):
  hw/i386/pc_sysfw: Remove unused parameter from pc_isa_bios_init()
  hw/i386/pc_sysfw: Alias rather than copy isa-bios region
  hw/i386/x86: Eliminate two if statements in x86_bios_rom_init()
  hw/i386: Consolidate isa-bios creation

 include/hw/i386/x86.h |  2 ++
 hw/i386/pc_sysfw.c    | 38 ++++----------------------------------
 hw/i386/x86.c         | 35 +++++++++++++++++++----------------
 3 files changed, 25 insertions(+), 50 deletions(-)

-- 
2.44.0

Re: [PATCH 0/4] X86: Alias isa-bios area and clean up
Posted by Bernhard Beschow 1 week, 4 days ago
+Michael 

Am 22. April 2024 20:06:21 UTC schrieb Bernhard Beschow <shentey@gmail.com>:
>This series changes the "isa-bios" MemoryRegion to be an alias rather than a
>
>copy in the pflash case. This fixes issuing pflash commands in the isa-bios
>
>region which matches real hardware and which some real-world legacy bioses I'm
>
>running rely on. Furthermore, aliasing in the isa-bios area is already the
>
>current behavior in the bios (a.k.a. ROM) case, so this series consolidates
>
>behavior.
>
>
>
>The consolidateion results in duplicate code which is resolved in the second
>
>half (patches 3 and 4) in this series.
>
>
>
>Question: AFAIU, patch 2 changes the behavior for SEV-enabled guests since the
>
>isa-bios area is now encrypted. Does this need compat machinery or is it a
>
>bugfix?
>
>
>
>Testing done:
>
>* `make check` with qemu-system-x86_64 (QEMU 8.2.2) installed. All tests
>
>  including migration tests pass.
>
>* `make check-avocado`
>
>
>
>Best regards,
>
>Bernhard
>
>
>
>Bernhard Beschow (4):
>
>  hw/i386/pc_sysfw: Remove unused parameter from pc_isa_bios_init()
>
>  hw/i386/pc_sysfw: Alias rather than copy isa-bios region
>
>  hw/i386/x86: Eliminate two if statements in x86_bios_rom_init()
>
>  hw/i386: Consolidate isa-bios creation
>
>
>
> include/hw/i386/x86.h |  2 ++
>
> hw/i386/pc_sysfw.c    | 38 ++++----------------------------------
>
> hw/i386/x86.c         | 35 +++++++++++++++++++----------------
>
> 3 files changed, 25 insertions(+), 50 deletions(-)
>
>
>
>-- >
>2.44.0
>
>
>
Re: [PATCH 0/4] X86: Alias isa-bios area and clean up
Posted by Philippe Mathieu-Daudé 1 week, 3 days ago
On 22/4/24 22:06, Bernhard Beschow wrote:
> This series changes the "isa-bios" MemoryRegion to be an alias rather than a
> copy in the pflash case. This fixes issuing pflash commands in the isa-bios
> region which matches real hardware and which some real-world legacy bioses I'm
> running rely on. Furthermore, aliasing in the isa-bios area is already the
> current behavior in the bios (a.k.a. ROM) case, so this series consolidates
> behavior.


> Bernhard Beschow (4):
>    hw/i386/pc_sysfw: Remove unused parameter from pc_isa_bios_init()

To reduce respin churn, I'm queuing the first patch via hw-misc.
Re: [PATCH 0/4] X86: Alias isa-bios area and clean up
Posted by Bernhard Beschow 1 week, 2 days ago

Am 25. April 2024 08:07:43 UTC schrieb "Philippe Mathieu-Daudé" <philmd@linaro.org>:
>On 22/4/24 22:06, Bernhard Beschow wrote:
>> This series changes the "isa-bios" MemoryRegion to be an alias rather than a
>> copy in the pflash case. This fixes issuing pflash commands in the isa-bios
>> region which matches real hardware and which some real-world legacy bioses I'm
>> running rely on. Furthermore, aliasing in the isa-bios area is already the
>> current behavior in the bios (a.k.a. ROM) case, so this series consolidates
>> behavior.
>
>
>> Bernhard Beschow (4):
>>    hw/i386/pc_sysfw: Remove unused parameter from pc_isa_bios_init()
>
>To reduce respin churn, I'm queuing the first patch via hw-misc.

Nice!
Re: [PATCH 0/4] X86: Alias isa-bios area and clean up
Posted by Michael S. Tsirkin 1 week, 3 days ago
On Mon, Apr 22, 2024 at 10:06:21PM +0200, Bernhard Beschow wrote:
> This series changes the "isa-bios" MemoryRegion to be an alias rather than a
> copy in the pflash case. This fixes issuing pflash commands in the isa-bios
> region which matches real hardware and which some real-world legacy bioses I'm
> running rely on. Furthermore, aliasing in the isa-bios area is already the
> current behavior in the bios (a.k.a. ROM) case, so this series consolidates
> behavior.
> 
> The consolidateion results in duplicate code which is resolved in the second
> half (patches 3 and 4) in this series.
> 
> Question: AFAIU, patch 2 changes the behavior for SEV-enabled guests since the
> isa-bios area is now encrypted. Does this need compat machinery or is it a
> bugfix?

When in doubt, do a compat thing.

> Testing done:
> * `make check` with qemu-system-x86_64 (QEMU 8.2.2) installed. All tests
>   including migration tests pass.
> * `make check-avocado`
> 
> Best regards,
> Bernhard
> 
> Bernhard Beschow (4):
>   hw/i386/pc_sysfw: Remove unused parameter from pc_isa_bios_init()
>   hw/i386/pc_sysfw: Alias rather than copy isa-bios region
>   hw/i386/x86: Eliminate two if statements in x86_bios_rom_init()
>   hw/i386: Consolidate isa-bios creation
> 
>  include/hw/i386/x86.h |  2 ++
>  hw/i386/pc_sysfw.c    | 38 ++++----------------------------------
>  hw/i386/x86.c         | 35 +++++++++++++++++++----------------
>  3 files changed, 25 insertions(+), 50 deletions(-)
> 
> -- 
> 2.44.0
>
Re: [PATCH 0/4] X86: Alias isa-bios area and clean up
Posted by Bernhard Beschow 1 week, 2 days ago

Am 25. April 2024 10:16:10 UTC schrieb "Michael S. Tsirkin" <mst@redhat.com>:
>On Mon, Apr 22, 2024 at 10:06:21PM +0200, Bernhard Beschow wrote:
>> This series changes the "isa-bios" MemoryRegion to be an alias rather than a
>> copy in the pflash case. This fixes issuing pflash commands in the isa-bios
>> region which matches real hardware and which some real-world legacy bioses I'm
>> running rely on. Furthermore, aliasing in the isa-bios area is already the
>> current behavior in the bios (a.k.a. ROM) case, so this series consolidates
>> behavior.
>> 
>> The consolidateion results in duplicate code which is resolved in the second
>> half (patches 3 and 4) in this series.
>> 
>> Question: AFAIU, patch 2 changes the behavior for SEV-enabled guests since the
>> isa-bios area is now encrypted. Does this need compat machinery or is it a
>> bugfix?
>
>When in doubt, do a compat thing.

Will do.

Thanks,
Bernhard

>
>> Testing done:
>> * `make check` with qemu-system-x86_64 (QEMU 8.2.2) installed. All tests
>>   including migration tests pass.
>> * `make check-avocado`
>> 
>> Best regards,
>> Bernhard
>> 
>> Bernhard Beschow (4):
>>   hw/i386/pc_sysfw: Remove unused parameter from pc_isa_bios_init()
>>   hw/i386/pc_sysfw: Alias rather than copy isa-bios region
>>   hw/i386/x86: Eliminate two if statements in x86_bios_rom_init()
>>   hw/i386: Consolidate isa-bios creation
>> 
>>  include/hw/i386/x86.h |  2 ++
>>  hw/i386/pc_sysfw.c    | 38 ++++----------------------------------
>>  hw/i386/x86.c         | 35 +++++++++++++++++++----------------
>>  3 files changed, 25 insertions(+), 50 deletions(-)
>> 
>> -- 
>> 2.44.0
>> 
>