WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xci-devel

Re: [Xen-devel] Re: [Xci-devel] Porblem with disabling and then re-enab

To: "Jiang, Yunhong" <yunhong.jiang@xxxxxxxxx>
Subject: Re: [Xen-devel] Re: [Xci-devel] Porblem with disabling and then re-enabling a PT device in Windows
From: Tom Rotenberg <tom.rotenberg@xxxxxxxxx>
Date: Thu, 26 Nov 2009 07:40:08 +0200
Cc: "xci-devel@xxxxxxxxxxxxxxxxxxx" <xci-devel@xxxxxxxxxxxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>, Kamala Narasimhan <Kamala.Narasimhan@xxxxxxxxxx>
Delivery-date: Wed, 25 Nov 2009 21:40:41 -0800
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=Lql16DhtisQmUsKAYoHchjKVV3nhLcWOXR+zIpw68kY=; b=D1JHx9TgQtVRDM4o6tLdxF4B3OhTYJTJVG3T7KsfbxYMcNl/9RNttVbegasZST23PU i3VN7ocBGY8GB5mjQJFbx+0fNWH1yKeY+2cZYooAhTFrsYg15F5GPvxAHD8LzYmO5I5/ 96Zb42LjnoGgTWaLil8bnuhZs+ZgU2F9JshWM=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=F1OOFc+OWsY6heG9YukO4SZ/nr2gINc3kuY3JsBrOJB+1JwJABrFkPk/I4RjnlhAKa 4wwUS9Ig92suQql7fz5hAvKoJOtYY5uZtPS0khj5efUKfDPxTFhIw36DEg0ZaskS8gYq ZdXUnMLCK4lcSums1fvs/cW7Rfcrshzc7xa/k=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <E2263E4A5B2284449EEBD0AAB751098418E57428BD@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <8686c3cd0911250508i5937d100k2cae23816e450bde@xxxxxxxxxxxxxx> <5997D0BE578D47409D1EBD41DFD341F489F5F54E85@xxxxxxxxxxxxxxxxxxxxxxxxx> <8686c3cd0911250621g7735507du4393721aac2aef05@xxxxxxxxxxxxxx> <5997D0BE578D47409D1EBD41DFD341F489F5F54E86@xxxxxxxxxxxxxxxxxxxxxxxxx> <8686c3cd0911250831y4e2e2e06s6eaf9e3829076853@xxxxxxxxxxxxxx> <8686c3cd0911251328x7d53675q98018c22ff41f299@xxxxxxxxxxxxxx> <E2263E4A5B2284449EEBD0AAB751098418E57428BD@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
How do i know if i'm using 'ack_type_new', what does it mean?
Do u have any idea, on how i can check inside domU windows XP (using
WinDBG of-course) if the virtual local APIC/IOAPIC has EOI the
interrupt?

It happens every time... it's 100% reproduceable on that Dell machine.

On Thu, Nov 26, 2009 at 3:40 AM, Jiang, Yunhong <yunhong.jiang@xxxxxxxxx> wrote:
>
>
> xen-devel-bounces@xxxxxxxxxxxxxxxxxxx wrote:
>> After digging more into this problem, i found out that the problem is
>> because the interrupt generated on the wlan device, isn't being
>> transfered to the domain, for some reason, after the device was
>> re-enablked in Windows. I saw that, by connecting to the xen console,
>> and then clicking 'i', and i got the following lines:
>> ...
>> (XEN)    Vec192 IRQ 17: type=IO-APIC-level   status=00000010
>> in-flight=1 domain-list=0: 17(----),3: 17(---M),
>> ...
>> (XEN)       Apic 0x00, Pin 17: vector=192, delivery_mode=1,
>> dest_mode=logical, delivery_status=1, polarity=1, irr=1,
>> trigger=level, mask=0 ....
>>
>> You can see, that the interrupt 17, which is in my Windows domU, was
>> generated, but still weren't injected to the CPU (the 'irr' is 1). So,
>> i guess that this is what is causing the problem.
>> Now, the only issue left, is why the hell, the interrupt isn't being
>> injected to the domain?
>
> I assume you are using ack_type_new on your system, am I right?
> Usually it means guest has not EOI the interrupt, so that host has no chance 
> to EOI the physical IOAPIC. Can you check the virtual Local APIC/IOAPIC for 
> the guest to see if we have any finding?
> BTW, does it happen everytime?
>
> --jyh
>
>>
>> Has anyone has any idea about it?
>>
>> On Wed, Nov 25, 2009 at 6:31 PM, Tom Rotenberg
>> <tom.rotenberg@xxxxxxxxx> wrote:
>>> Well, i just performed some tests, and it doesn't look like the
>>> disable_msi/enable_msi functions in pciback are being called at all
>>> (moreover, not in the disable-enable from domU Windows XP), so i
>>> don't think it's related. Also, since when, a config space write
>>> from a guest domU triggers code in the pciback?
>>>
>>> I think that it's not the problem here...
>>> Maybe someone from the XCI can shed some light here, and tell us how
>>> they solve it (or not)? since their code should run on the same Dell
>>> machines, no?
>>>
>>> On Wed, Nov 25, 2009 at 5:13 PM, Kamala Narasimhan
>>> <Kamala.Narasimhan@xxxxxxxxxx> wrote:
>>>> I shouldn't have suggested that you build without pciback;
>> I got carried away trying to make it simple for you :-);
>> Obviously you would need it and I should have stopped with
>> suggesting that you tweak it.
>>>>
>>>> Here is the thought process that led to my suggestion -
>>>>
>>>> Clearly, that bit is getting changed as indicated in your
>> log.  It is unlikely that the guest is triggering that change
>> which makes pciback a potential candidate to suspect as it
>> does change pci configuration space bits.  I need to add some
>> tracing and look at the path of execution to answer some of
>> your specific questions accurately and I won't be able to do
>> that right now but I can give some context to help you based
>> on what I have experienced in comparable situation and based
>> on that I would say pciback is one place to suspect.  To be a
>> bit more specific I would say look into
>> pciback_enable_msi/pciback_disable_msi code, add some tracing
>> there, observe whether or not that code path is taken when the
>> device is disabled/reenabled within guest etc.  To reiterate,
>> these are mere suggestions but looks plausible based on prior
>> observations.
>>>>
>>>> Kamala
>>>>
>>>>> -----Original Message-----
>>>>> From: Tom Rotenberg [mailto:tom.rotenberg@xxxxxxxxx]
>>>>> Sent: Wednesday, November 25, 2009 9:22 AM
>>>>> To: Kamala Narasimhan
>>>>> Cc: xen-devel@xxxxxxxxxxxxxxxxxxx; xci-devel@xxxxxxxxxxxxxxxxxxx
>>>>> Subject: Re: [Xci-devel] Porblem with disabling and then
>>>>> re-enabling a PT device in Windows
>>>>>
>>>>> I am not sure i undertand how to test it...
>>>>> 1) Avoid doing FLR for the device - isn';t that done only when
>>>>> building the domain? does that happen when i disable the device in
>>>>> domU? 2) Don't build pciback - and then, i won't bind the wlan
>>>>> device to pciback? and change the xend scripts which check for it?
>>>>> 3) Comment out the relevant code - which code??
>>>>>
>>>>> I also don't understand, how could it be that the pciback device is
>>>>> "messing" with it? isn't it supposed to be in-active when the
>>>>> device is being used in PT?
>>>>>
>>>>> Tom
>>>>>
>>>>> On Wed, Nov 25, 2009 at 4:12 PM, Kamala Narasimhan
>>>>> <Kamala.Narasimhan@xxxxxxxxxx> wrote:
>>>>>> There is a chance pciback is changing the bit you are referring
>>>>> to.  To confirm that, just for testing purpose you might want to
>>>>> avoid FLR for that device or simply not build pciback or comment
>>>>> out relevant code in that module whichever is easier and see if
>>>>> that helps.  If it does, you can then look into fixing the problem
>>>>> the right way.
>>>>>>
>>>>>> Kamala
>>>>>>
>>>>>>> -----Original Message-----
>>>>>>> From: xci-devel-bounces@xxxxxxxxxxxxxxxxxxx [mailto:xci-devel-
>>>>>>> bounces@xxxxxxxxxxxxxxxxxxx] On Behalf Of Tom Rotenberg
>>>>>>> Sent: Wednesday, November 25, 2009 8:09 AM
>>>>>>> To: xen-devel@xxxxxxxxxxxxxxxxxxx; xci-devel@xxxxxxxxxxxxxxxxxxx
>>>>>>> Subject: [Xci-devel] Porblem with disabling and then re-enabling
>>>>>>> a PT device in Windows
>>>>>>>
>>>>>>> Hi All,
>>>>>>>
>>>>>>> (This is a continuation to my previous mail, but since it looks
>>>>>>> like a different problem - i decided to open a new thread for it)
>>>>>>>
>>>>>>> ----
>>>>>>> Problem Description:
>>>>>>> ----
>>>>>>> I am doing pass-through of an Intel wireless LAN device to a
>>>>>>> Windows XP domU (my machine is Dell e6400), and it looks like
>>>>>>> it's working ok. Then, i disable the device using Windows device
>>>>>>> manager, and the device is now disabled, after that i re-enable
>>>>>>> the device, and Windows re-enables the device correctly.
>>>>>>> However, the wlan device seems to malfunction (it can't turn on
>>>>>>> the WiFi of the computer), and can't connect to wireless
>>>>>>> networks. I tried it, both with MSI translation on, and with MSI
>>>>>>> translation off - it doesn't matter.
>>>>>>>
>>>>>>> ----
>>>>>>> My analysis:
>>>>>>> ----
>>>>>>> 1) Well, taking a look at the real PCI config space, before
>>>>>>> disable and after the (last) enable, shows that the difference
>>>>>>> is at the Intx bit (read-only bit 3 at status register (offset
>>>>>>> 0x6) at the PCI config space). Before disable, that bit was 0,
>>>>>>> and after the last enable that bit was 1. This, according to my
>>>>>>> understanding, means that the device is asserting it's IntX ,
>>>>>>> and probably waiting for someone to handle it, no?
>>>>>>>
>>>>>>> 2) When i tried to track when did this bit was changed - i added
>>>>>>> a code which in every PCI config read, checks if that bit was
>>>>>>> changed - and added a print when it changed. The proper lines in
>>>>>>> the qemu log looks like this: ...
>>>>>>> pt_pci_read_config: [00:01.0]: address=00f0 val=0x00000000 len=2
>>>>>>> ACPI PCI hotplug: read addr=0x10c6, val=0x0f.
>>>>>>> ACPI PCI hotplug: read addr=0x10c6, val=0x0f.
>>>>>>> pt_pci_read_config: TEST CODE: STATUS CHNAGED! OLD: 0x10, NEW:
>>>>>>> 0x18 pt_pci_read_config: [00:01.0]: address=0000 val=0x00008086
>>>>>>> len=2 ...
>>>>>>>
>>>>>>> This implies that the bit was changed, about the same time that
>>>>>>> Windows tried to start using it (because, i assume that it tried
>>>>>>> using it, just after questioning the ACPI for the existence of
>>>>>>> the device). No?
>>>>>>>
>>>>>>>
>>>>>>> Can someone help me with this?
>>>>>>>
>>>>>>> (BTW - i am using Xen 3.4)
>>>>>>>
>>>>>>> Tom
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> Xci-devel mailing list
>>>>>>> Xci-devel@xxxxxxxxxxxxxxxxxxx
>>>>>>> http://lists.xensource.com/mailman/listinfo/xci-devel
>>>>>>
>>>>
>>>
>>
>> _______________________________________________
>> Xen-devel mailing list
>> Xen-devel@xxxxxxxxxxxxxxxxxxx
>> http://lists.xensource.com/xen-devel

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel