Re: [PATCH] igb: fix kexec with igb

From: Yinghai Lu
Date: Sun Mar 08 2009 - 17:20:37 EST


Rafael J. Wysocki wrote:
> On Sunday 08 March 2009, Yinghai Lu wrote:
>> Rafael J. Wysocki wrote:
>>> On Saturday 07 March 2009, Yinghai Lu wrote:
>>>> On Fri, Mar 6, 2009 at 11:18 PM, Jesse Brandeburg
>>>> <jesse.brandeburg@xxxxxxxxx> wrote:
>>>>> On Fri, Mar 6, 2009 at 8:33 PM, Yinghai Lu <yinghai@xxxxxxxxxx> wrote:
>>>>>> Impact: could probe igb
>>>>>>
>>>>>> Found one system with 82575EB, in the kernel that is kexeced, probe igb
>>>>>> failed with -2.
>>>>>>
>>>>>> it looks like the same behavior happened on forcedeth.
>>>>>>
>>>>>> try to check system_state to make sure if put it on D3
>>>>>>
>>>>>> Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
>>>>>>
>>>>>> ---
>>>>>> drivers/net/igb/igb_main.c | 19 ++++++++++++++-----
>>>>>> 1 file changed, 14 insertions(+), 5 deletions(-)
>>>>> I see the point of the patch, but I know for a fact that ixgbe when
>>>>> enabled for MSI-X also doesn't work with kexec.
>>>>>
>>>>> so my questions are:
>>>>> are you going to change every driver?
>>>> i tend to only change driver that i have related HW.
>>>>
>>>>> why can't this be fixed in core kernel code instead?
>>>> will check it.
>>>>
>>>>> Shouldn't pci_enable_device take it out of D3?
>>>>> Or maybe it should be taken out of D3 immediately if someone tries to
>>>>> ioremap any of the BARx registers?
>>>> looks like second kernel can not detect the state any more.
>>> In fact pci_enable_device() calls pci_set_power_state(dev, PCI_D0) as the first
>>> thing. The question is why it doesn't work as expected.
>> not sure... please check the version for forcedeth that you made.
>>
>> commit 3cb5599a84c557c0dd9a19feb63a3788268cf249
>> Author: Rafael J. Wysocki <rjw@xxxxxxx>
>> Date: Fri Sep 5 14:00:19 2008 -0700
>>
>> forcedeth: fix kexec regression
>>
>> Fix regression tracked as http://bugzilla.kernel.org/show_bug.cgi?id=11361
>> and caused by commit f735a2a1a4f2a0f5cd823ce323e82675990469e2 ("[netdrvr]
>> forcedeth: setup wake-on-lan before shutting down") that makes network
>> adapters integrated into the NVidia MCP55 chipsets fail to work in kexeced
>> kernels. The problem appears to be that if the adapter is put into D3_hot
>> during ->shutdown(), it cannot be brought back into D0 after kexec (ref.
>> http://marc.info/?l=linux-kernel&m=121900062814967&w=4). Therefore, only
>> put forcedeth into D3 during ->shutdown() if the system is to be powered
>> off.
>
> Thanks, I remember now.
>
> This appears to be quirky hardware, doesn't it?
>
all my systems with ck804 and mcp55 need this trick.

for igb: one system need this trick, and other doesn't need this trick.
could BIOS/ACPI difference or the nic option rom difference.

but for kexec path, we really don't need put pci devices to D3.

YH

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