Re: 3.9.0-rc1: kexec not working: root disk does not show up

[Konstantin Khlebnikov <khlebnikov@openvz.org>]

Vivek Goyal wrote:
> On Wed, Mar 13, 2013 at 06:53:16PM +0400, Konstantin Khlebnikov wrote:
>
> [..]
>> PCI: Don't try to disable Bus Master on disconnected PCI devices
>>
>> From: Konstantin Khlebnikov<khlebnikov@openvz.org>
>>
>> This is fix for commit 7897e6022761ace7377f0f784fca059da55f5d71 from v3.9-rc1
>> ("PCI: Disable Bus Master unconditionally in pci_device_shutdown()")
>> in turn that was fix for b566a22c23327f18ce941ffad0ca907e50a53d41 from v3.5-rc1
>> ("PCI: disable Bus Master on PCI device shutdown")
>>
>> Unfortunately fixing one bug uncovers another: after ->shutdown() device can be
>> already disconnected from the bus and configuration space in no longer available
>>
>> Link: https://lkml.org/lkml/2013/3/12/529
>> Signed-off-by: Konstantin Khlebnikov<khlebnikov@openvz.org>
>> Reported-by: Vivek Goyal<vgoyal@redhat.com>
>> Cc: Bjorn Helgaas<bhelgaas@google.com>
>> Cc: Rafael J. Wysocki<rafael.j.wysocki@intel.com>
>> ---
>>   drivers/pci/pci-driver.c |    5 +++--
>>   1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
>> index 1fa1e48..79277fb 100644
>> --- a/drivers/pci/pci-driver.c
>> +++ b/drivers/pci/pci-driver.c
>> @@ -390,9 +390,10 @@ static void pci_device_shutdown(struct device *dev)
>>
>>   	/*
>>   	 * Turn off Bus Master bit on the device to tell it to not
>> -	 * continue to do DMA
>> +	 * continue to do DMA. Don't touch devices in D3cold or unknown states.
>>   	 */
>> -	pci_clear_master(pci_dev);
>> +	if (pci_dev->current_state<= PCI_D3hot)
>> +		pci_clear_master(pci_dev);
>>   }
>>
>>   #ifdef CONFIG_PM
>
> Hi,
>
> Above patch fixed the issue on my box. Now I can kexec. Thanks.
>
> Vivek
>

Ok, thanks for testing.