Re: [PATCH] pci: fix unavailable irq number 255 reported by BIOS

[Chen Fan]

On 01/19/2016 11:39 PM, Rafael J. Wysocki wrote:
> On Tue, Jan 19, 2016 at 3:48 PM, Sinan Kaya <okaya@xxxxxxxxxxxxxx> wrote:
> > On 1/19/2016 9:20 AM, Rafael J. Wysocki wrote:
> > > On Tuesday, January 19, 2016 02:43:30 PM Rafael J. Wysocki wrote:
> > > > On Tuesday, January 19, 2016 09:45:13 AM Chen Fan wrote:
> > > > > In our environment, when enable Secure boot, we found an abnormal
> > > > > phenomenon as following call trace shows. after investigation, we
> > > > > found the firmware assigned an irq number 255 which means unknown
> > > > > or no connection in PCI local spec for i801_smbus, meanwhile the
> > > > > ACPI didn't configure the pci irq routing. and the 255 irq number
> > > > > was assigned for megasa msix without IRQF_SHARED. then in this case
> > > > > during i801_smbus probe, the i801_smbus driver would request irq with
> > > > > bad irq number 255. but the 255 irq number was assigned for memgasa
> > > > > with MSIX enable. which will cause request_irq fails, and call trace
> > > > > shows, actually, we should expose the error early, rather than in request
> > > > > irq, here we simply fix the problem by return err when find the irq is
> > > > > 255.
> > > > >
> > > > > See the call trace:
> > > > >
> > > > >   [   32.459195] ipmi device interface
> > > > >   [   32.612907] shpchp: Standard Hot Plug PCI Controller Driver version: 0.4
> > > > >   [   32.800459] ixgbe: Intel(R) 10 Gigabit PCI Express Network Driver - version 4.0.1-k-rh
> > > > >   [   32.818319] ixgbe: Copyright (c) 1999-2014 Intel Corporation.
> > > > >   [   32.844009] lpc_ich 0001:80:1f.0: I/O space for ACPI uninitialized
> > > > >   [   32.850093] i801_smbus 0000:00:1f.3: enabling device (0140 -> 0143)
> > > > >   [   32.851134] i801_smbus 0000:00:1f.3: can't derive routing for PCI INT C
> > > > >   [   32.851136] i801_smbus 0000:00:1f.3: PCI INT C: no GSI
> > > > >   [   32.851164] genirq: Flags mismatch irq 255. 00000080 (i801_smbus) vs. 00000000 (megasa
> > > > >   [   32.851168] CPU: 0 PID: 2487 Comm: kworker/0:1 Not tainted 3.10.0-229.el7.x86_64 #1
> > > > >   [   32.851170] Hardware name: FUJITSU PRIMEQUEST 2800E2/D3736, BIOS PRIMEQUEST 2000 Serie5
> > > > >   [   32.851178] Workqueue: events work_for_cpu_fn
> > > > >   [   32.851208]  ffff88086c330b00 00000000e233a9df ffff88086d57bca0 ffffffff81603f36
> > > > >   [   32.851227]  ffff88086d57bcf8 ffffffff8110d23a ffff88686fe02000 0000000000000246
> > > > >   [   32.851246]  ffff88086a9a8c00 00000000e233a9df ffffffffa00ad220 0000000000000080
> > > > >   [   32.851247] Call Trace:
> > > > >   [   32.851261]  [<ffffffff81603f36>] dump_stack+0x19/0x1b
> > > > >   [   32.851271]  [<ffffffff8110d23a>] __setup_irq+0x54a/0x570
> > > > >   [   32.851282]  [<ffffffffa00ad220>] ? i801_check_pre.isra.5+0xe0/0xe0 [i2c_i801]
> > > > >   [   32.851289]  [<ffffffff8110d3bc>] request_threaded_irq+0xcc/0x170
> > > > >   [   32.851298]  [<ffffffffa00ae87f>] i801_probe+0x32f/0x508 [i2c_i801]
> > > > >   [   32.851308]  [<ffffffff81308385>] local_pci_probe+0x45/0xa0
> > > > >   [   32.851315]  [<ffffffff8108bfd4>] work_for_cpu_fn+0x14/0x20
> > > > >   [   32.851323]  [<ffffffff8108f0ab>] process_one_work+0x17b/0x470
> > > > >   [   32.851330]  [<ffffffff81090003>] worker_thread+0x293/0x400
> > > > >   [   32.851338]  [<ffffffff8108fd70>] ? rescuer_thread+0x400/0x400
> > > > >   [   32.851346]  [<ffffffff8109726f>] kthread+0xcf/0xe0
> > > > >   [   32.851353]  [<ffffffff810971a0>] ? kthread_create_on_node+0x140/0x140
> > > > >   [   32.851362]  [<ffffffff81613cfc>] ret_from_fork+0x7c/0xb0
> > > > >   [   32.851369]  [<ffffffff810971a0>] ? kthread_create_on_node+0x140/0x140
> > > > >   [   32.851373] i801_smbus 0000:00:1f.3: Failed to allocate irq 255: -16
> > > > >   [   32.851435] i801_smbus: probe of 0000:00:1f.3 failed with error -16
> > > > >   [   33.180145] ixgbe 0000:5a:00.0: Multiq[   33.240538] ixgbe 0000:5a:00.0: (PCI Express:03:e0
> > > > >   [   33.280826] ixgbe 0000:5a:00.0: MAC: 3, PHY: 0, PBA No: 000000-000
> > > > >
> > > > > Signed-off-by: Chen Fan <chen.fan.fnst@xxxxxxxxxxxxxx>
> > > > > ---
> > > > >   drivers/acpi/pci_irq.c | 10 +++++++++-
> > > > >   1 file changed, 9 insertions(+), 1 deletion(-)
> > > > >
> > > > > diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c
> > > > > index d30184c..d2f47f8 100644
> > > > > --- a/drivers/acpi/pci_irq.c
> > > > > +++ b/drivers/acpi/pci_irq.c
> > > > > @@ -439,9 +439,17 @@ int acpi_pci_irq_enable(struct pci_dev *dev)
> > > > >              if (acpi_isa_register_gsi(dev))
> > > > >                      dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
> > > > >                               pin_name(pin));
> > > > > +           rc = 0;
> > > > > +           /*
> > > > > +            * Excluding the BIOS report the value 255, which meaning
> > > > > +            * "unknown" or "no connection" in PCI Local Bus Specification
> > > > > +            * Revision 3.0 February 3, 2004, P223.
> > > > You mean the footnote on page 223 talking about the Interrupt Line values, right?
> > "Unknown" does not necessarily mean invalid. I have a platform that is using 255 as a valid legacy
> > interrupt on PCI Express.
> So first off this is about the Interrupt Line value not about an
> interrupt vector.
>
> Second, the footnote in question is talking about x86 PCs, so if your
> platform is not one of them, there is no connection here.
>
> Which means that the change should be limited to x86 probably.
That's right, we should wrap this code in arch x86.

Thanks,
Chen

> Thanks,
> Rafael
>
>
> .