Re: [Bugfix 0/3] Xen IRQ related hotfixes for v3.19

[Sander Eikelenboom <linux@eikelenboom.it>]

Monday, February 9, 2015, 5:09:44 PM, you wrote:

> On 09.02.2015 13:29, Stefan Bader wrote:
>> On 09.02.2015 13:12, Jiang Liu wrote:
>>> On 2015/2/9 17:47, Stefan Bader wrote:
>>>> On 05.02.2015 21:07, Sander Eikelenboom wrote:
>>>>>
>>>>> Tuesday, January 20, 2015, 3:21:04 AM, you wrote:
>>>>>
>>>>>> Hi Thomas,
>>>>>>         This patch set includes three hotfixes related Xen IRQ for v3.19.
>>>>>> Sorry for the long delay to get these two regressions fixed, it really
>>>>>> cost me some time to read and understand Xen IRQ code.
>>>>>
>>>>>> Patch 1 fixes the failure to register ACPI SCI interrupt on Xen
>>>>>> domain0 by reworking acpi_gsi_to_irq(). I will backport it to v3.18
>>>>>> too once it reaches the mainstream kernel.
>>>>>
>>>>>> Patch 2 fixes the regression in Xen PCI device passthrough(pciback).
>>>>>> It's a temporary solution, I will send the formal fix for v3.20 and
>>>>>> it has passed tests too.
>>>>>
>>>>>> Patch 3 fixes an issue found when reading code. There's no real bug
>>>>>> reports related to this issue yet.
>>>>>
>>>>>> Great thanks to Konrad and Sander for testing fixes for these regressions.
>>>>>
>>>>>> Regards,
>>>>>> Gerry
>>>>>
>>>>> Hi Gerry,
>>>>>
>>>>> Since these patches now are: tested, reviewed and have landed into mainline,
>>>>> could you also provide the backports for 3.17 and 3.18 where required ?
>>>>
>>>> This would be my attempt of backporting those to 3.18 (I have not tried whether
>>>> they would apply to 3.17 as well). Those seem to work when test-booting and
>>>> Sander said he will give them a try as well. But better check yourself I did not
>>>> mess anything up while backporting. One of the three patches seemed not to be
>>>> required at all.
>>> I'm backporting them too, but now I will give up my patches:)
>>>
>>> The first one is a must, which should be applied to 3.17 and 3.18.
>>> The second one doesn't apply to 3.17 or 3.18.
>>> The third may be applied to v3.17 and v3.18, but it shouldn't be applied
>>> according to the stable-kernel doc because no user reports such a bug yet.
>> 
>> Hm, ok. So maybe I should retry with only patch#1 and verify that alone gets
>> around the acpi irq and the usb problems, too. Though interestingly from the
>> history, the acpi irq I saw in 3.17 while the usb devices started to fail with
>> 3.18. I will let you know in a bit. Just want to finish another bisect first.

> So it looks like patch #1 indeed does fix both the acpi irq and my usb devices.
> Sander, do you want to verify that variant, too?

Will test 3.18 with only patch 1 after dinner.

> The only odd thing left in a 3.18 with the fix (regardless of using patch #1
> only or patches #1 and #3) is that the ahci driver shows up with its pci bus
> number in /proc/interrupts. But that does not seem to have any relevant downside
> (cannot try 3.19 on that box right now for other reasons).

> -Stefan

> ...
> # 57: 12441  0    0    0  xen-pirq-msi       0000:00:1f.2
> #                                            (used to be ahci)

Hmm funky .. now that you mention it .. i'm seeing that as well but only on an 
intel machine.

intel .. on 3.19:
 52:      13529          0          0          0  xen-pirq-msi       0000:00:1f.2
 
on my amd machine on 3.19 it seems ok though:

 114:     412535          0          0          0          0          0  xen-pirq-msi       ahci0
 115:          0          0          0          0          0          0  xen-pirq-msi       ahci1
 116:      16717          0          0          0          0          0  xen-pirq-msi       ahci2
 117:          0          0          0          0          0          0  xen-pirq-msi       ahci3
 118:          0          0          0          0          0          0  xen-pirq-msi       ahci4
 119:          0          0          0          0          0          0  xen-pirq-msi       ahci5

--
Sander

>> 
>> -Stefan
>> 
>>> Regards
>>> Gerry
>>>>
>>>> -Stefan
>>>>
>>>>>
>>>>> The number of people running into these (subtle) issues with these stable
>>>>> kernels seems to be steadily increasing.
>>>>>
>>>>> --
>>>>> Sander
>>>>>
>>>>>> Jiang Liu (3):
>>>>>>   xen/pci: Kill function xen_setup_acpi_sci()
>>>>>>   xen/irq, ACPI: Fix regression in xen PCI passthrough caused by
>>>>>>     cffe0a2b5a34
>>>>>>   xen/irq: Override ACPI IRQ management callback __acpi_unregister_gsi
>>>>>
>>>>>>  arch/x86/include/asm/acpi.h |    1 +
>>>>>>  arch/x86/kernel/acpi/boot.c |   26 +++++++++++------------
>>>>>>  arch/x86/pci/xen.c          |   49 ++-----------------------------------------
>>>>>>  drivers/acpi/pci_irq.c      |    1 -
>>>>>>  4 files changed, 16 insertions(+), 61 deletions(-)
>>>>>
>>>>>
>>>>
>> 
>>