bcm4708-smartrg-sr400ac boot failures in next/arm-soc

[Russell King - ARM Linux]

On Fri, Jan 08, 2016 at 03:59:16PM -0800, Tyler Baker wrote:
> On 8 January 2016 at 15:44, Russell King - ARM Linux
> <linux at arm.linux.org.uk> wrote:
> > On Fri, Jan 08, 2016 at 03:17:19PM -0800, Tyler Baker wrote:
> >> On 8 January 2016 at 14:50, Russell King - ARM Linux
> >> <linux at arm.linux.org.uk> wrote:
> >> > On Fri, Jan 08, 2016 at 02:33:39PM -0800, Tyler Baker wrote:
> >> >> After a bit of investigation, I determined that CONFIG_BLK_DEV_RAM was
> >> >> causing the issue and disabling it fixed the boot issue. Essentially,
> >> >> the kernel cannot find the initrd that has been loaded into memory by
> >> >> CFE bootloader with this option enabled as I inject the following
> >> >> command line into the DT before it's loaded over tftp.
> >> >>
> >> >> Loaded in CFE by: 'load -raw -tftp -addr=0x4000000 -max=0x900000
> >> >> 192.168.2.2:tmpqC9zOv/ramdisk.cpio.gz'
> >> >>
> >> >> Kernel arguments injected into DT: 'console=ttyS0,115200
> >> >> initrd=0x4000000,8M root=/dev/ram0 ip=dhcp'
> >> >
> >> > What is the problem that the kernel is reporting?
> >>
> >> The kernel complaining that there is no file system to mount, and
> >> panics. Here is a plain text version of the issue if you want to have
> >> a look[1].
> >
> > Thanks.
> >
> > The error is:
> >
> > [   16.557922] RAMDISK: EOF while reading compressed data
> >
> > which is not surprising given:
> >
> > initrd=0x4000000,8M
> >
> > is given on the kernel command line, but:
> >
> > Loader:raw Filesys:tftp Dev:eth0 File:192.168.2.2:tmpd9L7xr/ramdisk.cpio.gz Options:(null)
> > ... 8450989 bytes read
> >
> > the actual ramdisk is larger than 8M.  8M would've been 8388608 bytes,
> > but you're about 64k over that.
> 
> Right, this was my initial reaction when I saw this issue. I've
> attempted increase initrd limit passed to the kernel, the load size in
> the bootloader (10MB+) and still the same issue occurs when I do this.

Your ramdisk is 8450989 bytes.  You're telling _the kernel_ that it is
only 8388608 bytes.  The kernel is reporting that it reached the last
byte of the 8388608 and the decompression was not complete.

You need to tell the kernel that the ramdisk is bigger.  It's not the
bootloader, it's your "initrd=0x4000000,8M" argument to the kernel that's
causing the problem.

Increase that ",8M" to the kernel.

> I am suspicious that the CFE bootloader may have some limitation on
> initrd size it will load, even though it does not complain when I
> increase the size. I was hoping Hauke or Rafal might be able help us
> understand a bit more here, as they are maintainers of this platform.

It doesn't look like a platform issue, it looks like an incorrect
kernel argument issue.  The kernel is doing exactly what you've
asked it to do!

-- 
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