Re: Regression in kernel 3.5 as Dom0 regarding PCI Passthrough?!

[Tobias Geiger <tobias.geiger@vido.info>]

FYI:

This Dom0-Crash only happens, when i shuttdown the DomU within the 
DomU, meaning when i choose "Start - Shutdown" within Windows7.
The Crash does NOT happen, when i do "xl shutdown domu" ... ?! :)

Greetings
Tobias

Am 05.09.2012 20:54, schrieb Konrad Rzeszutek Wilk:
>> > > > And its due to a patch I added in v3.4
>> > > > (cd9db80e5257682a7f7ab245a2459648b3c8d268)
>> > > > - which did not work properly in v3.4, but with v3.5 got it 
>> working
>> > > > (977f857ca566a1e68045fcbb7cfc9c4acb077cf0) which causes v3.5 
>> to
>> > now
>> > > > work
>> > > > anymore.
>> > > >
>> > > > Anyhow, for right now jsut revert
>> > > > cd9db80e5257682a7f7ab245a2459648b3c8d268
>> > > > and it should work for you.
>> > > >
>> Confirmed, after reverting that commit, VT-d will work fine.
>> Will you fix this and push it to upstream Linux, Konrad?
>>
>> > > Also, our team reported a VT-d bug 2 months ago.
>> > > http://bugzilla.xen.org/bugzilla/show_bug.cgi?id=1824
>> >
>
> Can either one of you please test this patch, please:
>
>
> diff --git a/drivers/xen/xen-pciback/pci_stub.c
> b/drivers/xen/xen-pciback/pci_stub.c
> index 097e536..425bd0b 100644
> --- a/drivers/xen/xen-pciback/pci_stub.c
> +++ b/drivers/xen/xen-pciback/pci_stub.c
> @@ -4,6 +4,8 @@
>   * Ryan Wilson <hap9@epoch.ncsc.mil>
>   * Chris Bookholt <hap10@epoch.ncsc.mil>
>   */
> +#define DEBUG 1
> +
>  #include <linux/module.h>
>  #include <linux/init.h>
>  #include <linux/rwsem.h>
> @@ -97,13 +99,15 @@ static void pcistub_device_release(struct kref 
> *kref)
>  	/* Call the reset function which does not take lock as this
>  	 * is called from "unbind" which takes a device_lock mutex.
>  	 */
> +	dev_dbg(&psdev->dev->dev, "FLR locked..\n");
>  	__pci_reset_function_locked(psdev->dev);
>  	if (pci_load_and_free_saved_state(psdev->dev,
>  					  &dev_data->pci_saved_state)) {
>  		dev_dbg(&psdev->dev->dev, "Could not reload PCI state\n");
> -	} else
> +	} else {
> +		dev_dbg(&psdev->dev->dev, "Reloading PCI state..\n");
>  		pci_restore_state(psdev->dev);
> -
> +	}
>  	/* Disable the device */
>  	xen_pcibk_reset_device(psdev->dev);
>
> @@ -353,16 +357,16 @@ static int __devinit pcistub_init_device(struct
> pci_dev *dev)
>  	if (err)
>  		goto config_release;
>
> -	dev_dbg(&dev->dev, "reseting (FLR, D3, etc) the device\n");
> -	__pci_reset_function_locked(dev);
> -
>  	/* We need the device active to save the state. */
>  	dev_dbg(&dev->dev, "save state of device\n");
>  	pci_save_state(dev);
>  	dev_data->pci_saved_state = pci_store_saved_state(dev);
>  	if (!dev_data->pci_saved_state)
>  		dev_err(&dev->dev, "Could not store PCI conf saved state!\n");
> -
> +	else {
> +		dev_dbg(&dev->dev, "reseting (FLR, D3, etc) the device\n");
> +		__pci_reset_function_locked(dev);
> +	}
>  	/* Now disable the device (this also ensures some private device
>  	 * data is setup before we export)
>  	 */