Re: [Qemu-devel] [PATCH v4 0/6] KVM flash memory support

[Jordan Justen]

On Tue, May 7, 2013 at 1:28 PM, Paolo Bonzini <address@hidden> wrote:
> Il 07/05/2013 19:15, Jordan Justen ha scritto:
>> git://github.com/jljusten/qemu.git kvm-flash-v4
>>
>> Utilize KVM_CAP_READONLY_MEM to support PC system flash emulation
>> with KVM.
>>
>> v4:
>>  * With a machine type of isapc, don't mark the BIOS as read-only.
>>    isapc + seabios will not boot if the BIOS is read-only. This
>>    matches the current behavior of isapc with KVM, which is the
>>    only mode under which isapc currently works.
>
> Thanks for looking at it!
>
> Patch 1 should definitely be 1.5 material.  At this point it is late for
> 1.5 and I found a small problem in patch 3, so let's defer it.
>
> However, I'm thinking of reverting commit 9953f8822 in 1.5.  Yes, it's a
> bugfix but the change is only visible in TCG and having three modes in
> three versions is uselessly complicated.

This would be nice. I was definitely not excited about 1.5 having yet
another compatibility mode with regards to how PC system firmware
behaves. (And, having to try to document this...)

-Jordan

> Paolo
>
>> v3:
>>  * Squash patch 2 & 3 based on Xiao's feedback that what I
>>    was calling a 'workaround' in patch 3 was actually what
>>    is required by the KVM READONLY memory support.
>>
>> v2:
>>  * Remove rom_only from PC_COMPAT_1_4
>>  * Only enable flash when a pflash drive is created.
>>
>> Jordan Justen (6):
>>   isapc: Fix non-KVM qemu boot (read/write memory for isapc BIOS)
>>   kvm: add kvm_readonly_mem_enabled
>>   kvm: support using KVM_MEM_READONLY flag for readonly regions
>>   pflash_cfi01: memory region should be set to enable readonly mode
>>   pc_sysfw: allow flash (-pflash) memory to be used with KVM
>>   pc_sysfw: change rom_only default to 0
>>
>>  hw/block/pc_sysfw.c     |   64 
>> ++++++++++++++++++++++++++++++-----------------
>>  hw/block/pflash_cfi01.c |    2 ++
>>  hw/i386/pc_piix.c       |    5 ++++
>>  include/hw/i386/pc.h    |    4 ---
>>  include/sysemu/kvm.h    |   10 ++++++++
>>  kvm-all.c               |   42 ++++++++++++++++++++++++-------
>>  kvm-stub.c              |    1 +
>>  7 files changed, 92 insertions(+), 36 deletions(-)
>>
>
>