Re: [PATCH v2 1/3] Add vmware_hw to xl.cfg

[Don Slutz <dslutz@verizon.com>]

On 09/08/14 09:21, Ian Campbell wrote:
> On Wed, 2014-09-03 at 06:59 -0400, Don Slutz wrote:
>> On 09/03/14 03:45, Jan Beulich wrote:
>>>>>> On 02.09.14 at 20:24, <dslutz@verizon.com> wrote:
>>>> On 09/02/14 03:28, Jan Beulich wrote:
>>>>>>>> On 01.09.14 at 17:33, <dslutz@verizon.com> wrote:
>>>>>> @@ -149,8 +152,11 @@ void pci_setup(void)
>>>>>>                 pci_writew(devfn, 0x20, 0x0000); /* No smb bus IO enable */
>>>>>>                 pci_writew(devfn, 0xd2, 0x0000); /* No smb bus IO enable */
>>>>>>                 pci_writew(devfn, 0x22, 0x0000);
>>>>>> -            pci_writew(devfn, 0x3c, 0x0009); /* Hardcoded IRQ9 */
>>>>>> -            pci_writew(devfn, 0x3d, 0x0001);
>>>>>> +            if ( !vmware_hw )
>>>>>> +            {
>>>>>> +                pci_writew(devfn, 0x3c, 0x0009); /* Hardcoded IRQ9 */
>>>>>> +                pci_writew(devfn, 0x3d, 0x0001);
>>>>>> +            }
>>>>> This needs an explanation (it is merely being mentioned in the
>>>>> description).
>>>> Ok, how does this comment sound:
>>>>
>>>> /*
>>>>     * When looking more like VMware, let the guest pick the
>>>>     * PCI_INTERRUPT_LINE (0x3c) and the PCI_INTERRUPT_PIN(3d)
>>>>     * instead of them being hardcoded.  This allows for example
>>>>     * lscpci in the guest to match for "PIIX4 ACPI PM" what
>>>>     * one gets on VMware.
>>>>     */
>>> The first sentence is just stating verbally what the code does, i.e.
>>> pretty pointless. The second sentence - at least to me - doesn't
>>> explain anything (to a large part perhaps because having lspci
>>> produce identical output with real VMware is rather secondary a
>>> goal imo).
>> I can agree on it being a secondary goal, and so will drop it.
>>
>> I just remembered that the better statement:
>>
>> Attempt to reduce windows reactivations by making the hardware
>> look as much like VMware's.
> On the contrary avoiding the need to reactivate Windows seems like a
> pretty good primary reason for this change, isn't it? (or maybe I don't
> quite get what a reactivation is and how costly it is for the admin...)

I agree, but since this is 1 of about 20 similar changes (all the rest are
in QEMU), I am happy to defer this to 4.6 time frame.

Windows reactivation can at some times be expensive because Microsoft says you
have activated too many times with this license, you need a new one...

And it more effects smaller shops that have not paid the big bucks for a site
license.


     -Don Slutz


> Ian.
>
>
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