Comment # 16 on bug 907039 from Takashi Iwai

(In reply to Joschi Brauchle from comment #15)
> Hi there,
> 
> we are seeing this:
> -----------------
> kernel: [drm:cpt_set_fifo_underrun_reporting] *ERROR* uncleared pch fifo
> underrun on pch transcoder A
> kernel: [drm:cpt_serr_int_handler] *ERROR* PCH transcoder A FIFO underrun
> -----------------
> with a 
> -----------------
> 09: PCI 02.0: 0300 VGA compatible controller (VGA)              
>   [Created at pci.328]
>   Unique ID: _Znp.B56NdSxIhXD
>   SysFS ID: /devices/pci0000:00/0000:00:02.0
>   SysFS BusID: 0000:00:02.0
>   Hardware Class: graphics card
>   Model: "Intel 3rd Gen Core processor Graphics Controller"
>   Vendor: pci 0x8086 "Intel Corporation"
>   Device: pci 0x0166 "3rd Gen Core processor Graphics Controller"
>   SubVendor: pci 0x10cf "Fujitsu Limited."
>   SubDevice: pci 0x16c1 
>   Revision: 0x09
>   Driver: "i915"
>   Driver Modules: "drm"
>   Memory Range: 0xf0000000-0xf03fffff (rw,non-prefetchable)
>   Memory Range: 0xe0000000-0xefffffff (ro,non-prefetchable)
>   I/O Ports: 0x3000-0x303f (rw)
>   IRQ: 42 (61 events)
>   I/O Ports: 0x3c0-0x3df (rw)
>   Module Alias: "pci:v00008086d00000166sv000010CFsd000016C1bc03sc00i00"
>   Driver Info #0:
>     Driver Status: i915 is active
>     Driver Activation Cmd: "modprobe i915"
>   Config Status: cfg=new, avail=yes, need=no, active=unknown
> 
> Primary display adapter: #9
> -----------------
> 
> It is not 100% identical to the reported message in c#1, but possibly its
> the same 'warning-is-now-considered-error' problem?

The reason why now appears is the same, the message was promoted as a warning
now.  But the cause is definitely different from Jean's case.  So there is no
need to handle in the same bug.

> There are further references here:
> https://bugzilla.kernel.org/show_bug.cgi?id=79261
> 
> I can open a seperate BZ if needed.
> 
> Has the mentioned commit b68362278af94e1171f5be9d4e44988601fb0439 been
> released on 13.2 yet?

The patch was already backported, but it wno't cover your messages, as these
appear even on 3.19 kernel.  That implies that it's no help to track this on
this bugzilla.  Rather report to upstream bugzilla (either freedesktop.org or
kernel.org) and track there wiht the latest kernel.