Re: [Qemu-devel] [PATCH v12 2/5] apic: use per CPU AS to map APIC MMIO for TCG

[Zhu Guihua <zhugh.fnst@cn.fujitsu.com>]

On 10/03/2015 03:21 AM, Eduardo Habkost wrote:
> On Fri, Oct 02, 2015 at 03:24:24PM -0300, Eduardo Habkost wrote:
>> On Tue, Sep 22, 2015 at 02:29:01PM +0200, Igor Mammedov wrote:
>>> On Wed, 16 Sep 2015 17:19:12 +0800
>>> Zhu Guihua <zhugh.fnst@cn.fujitsu.com> wrote:
>>>
>>>> TCG supports per CPU address space, and the emulation quality is
>>>> a bit better with it.
>>>> So use per CPU address space to map APIC MMIO area. This allows the
>>>> APIC base address of each cpu to be moved independent of others.
>>>>
>>>> Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com>
>>> Reviewed-by: Igor Mammedov <imammedo@redhat.com>
>> The series seems to be OK when using KVM, but something is wrong with TCG.
>>
>> After applying this patch, my Fedora 20 image hangs on boot at:
>>
>> [  OK  ] Started udev Coldplug all Devices.
>>           Starting dracut initqueue hook...
>> [  OK  ] Reached target System Initialization.
>> [  OK  ] Reached target Basic System.
>> [    8.988420] ACPI: PCI Interrupt Link [LNKD] enabled at IRQ 11
>>
>>
>> Before this patch, boot continues with:
>>
>> [  OK  ] Reached target Basic System.
>> [    8.523293] ACPI: PCI Interrupt Link [LNKD] enabled at IRQ 11
>> [    9.230955]  vda: vda1
>> [  OK  ] Started dracut initqueue hook.
>>           Mounting /sysroot...
>>
>> I am running QEMU as:
>>    $ ./x86_64-softmmu/qemu-system-x86_64 -drive if=virtio,file=/home/ehabkost/system/vmachines/Fedora-x86_64-20-20131211.1-sda.qcow2,format=qcow2 -machine pc,accel=tcg  -smp 8,sockets=2,threads=2,cores=2,maxcpus=16 -serial stdio -nographic -monitor none
> Debugging revealed that this broke MSI delivery of virtio notifications.
> Writes to PCIDevice::bus_master_as (at msi_send_message()) don't get
> delivered to the APIC memory region anymore.
>
> This patch doesn't seem to be required for the removal of ICC bus, so I
> am applying the rest of the series anyway. If you see any problem with
> that, please let me know.
>
Sorry for late reply.   I'll look at this.

Thanks,
Zhu