[meta-intel] [PATCH 4/5] fri2.conf: fix boot time kernel errors

[Kamble, Nitin A]

> -----Original Message-----
> From: Hart, Darren
> Sent: Thursday, January 31, 2013 12:41 PM
> To: Kamble, Nitin A
> Cc: Zanussi, Tom; meta-intel at yoctoproject.org
> Subject: Re: [PATCH 4/5] fri2.conf: fix boot time kernel errors
> 
> On 01/31/2013 12:36 PM, Kamble, Nitin A wrote:
> >
> >
> >> -----Original Message-----
> >> From: Zanussi, Tom
> >> Sent: Thursday, January 31, 2013 12:33 PM
> >> To: Kamble, Nitin A
> >> Cc: Hart, Darren; meta-intel at yoctoproject.org
> >> Subject: Re: [PATCH 4/5] fri2.conf: fix boot time kernel errors
> >>
> >> On Thu, 2013-01-31 at 12:15 -0600, Kamble, Nitin A wrote:
> >>>
> >>>> -----Original Message-----
> >>>> From: Hart, Darren
> >>>> Sent: Thursday, January 31, 2013 8:17 AM
> >>>> To: Kamble, Nitin A
> >>>> Cc: Zanussi, Tom; meta-intel at yoctoproject.org
> >>>> Subject: Re: [PATCH 4/5] fri2.conf: fix boot time kernel errors
> >>>>
> >>>> On 01/30/2013 01:59 PM, nitin.a.kamble at intel.com wrote:
> >>>>> From: Nitin A Kamble <nitin.a.kamble at intel.com>
> >>>>>
> >>>>> The fri2 kernel is hitting kernel BUGs while booting. See the YP
> >>>>> bug
> >>>>> #3810 for more details.
> >>>>
> >>>> Please include details of the BUGs in the commit message.
> >>> Ok, That will make the commit message bit longer.
> >>>
> >>>>
> >>>>>
> >>>>> FRI2 has 1GB of ram, hence the kernel sets 128MB for the vmalloc
> >>>>> allocation memory. And the emgd driver needs at least 256MB
> >>>>> vmalloc memory to work correctly. This commit specifies the
> >>>>> vmalloc allocation size to the kernel by the vmalloc=256MB boot
> >> parameter.
> >>>>>
> >>>>> Adjusting the kernel's vmalloc allocation size fixes the kernel errors.
> >>>>>
> >>>>
> >>>> OK.... why haven't we seen this in the past? We shipped a ton of
> >>>> these which didn't see this. Has something else changed recently?
> >>>> EMGD
> >> version maybe?
> >>>
> >>>
> >>> I have seen this in the past with crownbay or emenlow BSPs which
> >>> also use EMGD for graphics. Also the emgd is updated to 1.16 now,
> >>> may be it is more aggressive with memory allocation.
> >>>
> >>
> >> Hmm, I just saw your patch upgrading fri2 to emgd 1.16 - so was this
> >> tested with 1.14 or 1.16?  And did the bug occur with 1.14 or 1.16?
> >>
> >> Tom
> >>
> >
> >
> >     The fix for the memory allocation issue is for both versions of EMGD.
> 
> 
> So it failed on both?
Yes,

> 
> This is odd as I have booted 1.14 many times without this parameter. I'd like
> to understand why, but I fear it isn't really worth the effort. I believe the
> EMGD guide states it needs 256?

Yes, the EMGD documentation specifies this vmalloc=256MB parameter.

Nitin


> 
> --
> Darren
> 
> 
> >
> > Nitin
> >
> >>>>
> >>>>> This fixes bug:
> >>>>> [Yocto #3810]
> >>>>>
> >>>>> Signed-off-by: Nitin A Kamble <nitin.a.kamble at intel.com>
> >>>>> ---
> >>>>>  meta-fri2/conf/machine/fri2.conf |    2 +-
> >>>>>  1 files changed, 1 insertions(+), 1 deletions(-)
> >>>>>
> >>>>> diff --git a/meta-fri2/conf/machine/fri2.conf
> >>>>> b/meta-fri2/conf/machine/fri2.conf
> >>>>> index 40f2cdc..6ee2335 100644
> >>>>> --- a/meta-fri2/conf/machine/fri2.conf
> >>>>> +++ b/meta-fri2/conf/machine/fri2.conf
> >>>>> @@ -37,4 +37,4 @@ SERIAL_CONSOLE = "115200 ttyPCH1"
> >>>>>  APPEND += "console=ttyPCH1,115200 console=tty0"
> >>>>>
> >>>>>  # EFI boot will ignore this and use the EFI framebuffer at
> >>>>> 800x600
> >>>>
> >>>> This comment needs to be updated. Perhaps adding vmalloc on a
> >>>> separate line would make it clearer. The vmalloc line specifically
> >>>> needs to be documented.
> >>> Ok, will split the line.
> >>>
> >>> Thanks,
> >>> Nitin
> >>>
> >>>
> >>>>
> >>>>> -APPEND += "video=vesafb vga=0x318"
> >>>>> +APPEND += "video=vesafb vga=0x318 vmalloc=256MB"
> >>>>>
> >>>>
> >>>> --
> >>>> Darren Hart
> >>>> Intel Open Source Technology Center Yocto Project - Linux Kernel
> >>
> >
> 
> --
> Darren Hart
> Intel Open Source Technology Center
> Yocto Project - Linux Kernel