Unable to boot linux-next build

On 9 September 2016 at 13:47, Quentin Lambert [off-list ref] wrote:

On 09/09/2016 09:33, PrasannaKumar Muralidharan wrote:

quoted

On 8 September 2016 at 18:16, Quentin Lambert [off-list ref]
wrote:

quoted

  I have been trying to build and boot the last version available on
linux-next.
  During the build I am being prompted with "has no CRC!" warnings for a
bunch
  of modules.

  Has a result I get the following lines in the Module.symvers:

  [qlambert at sloth linux-next]$ grep 0x00000 Module.symvers
  0x00000000     phys_base       vmlinux EXPORT_SYMBOL
  0x00000000     memmove vmlinux EXPORT_SYMBOL
  0x00000000     __copy_user_nocache     vmlinux EXPORT_SYMBOL
  0x00000000     __get_user_4    vmlinux EXPORT_SYMBOL
  0x00000000     __put_user_4    vmlinux EXPORT_SYMBOL
  0x00000000     __memcpy        vmlinux EXPORT_SYMBOL
  0x00000000     __fentry__      vmlinux EXPORT_SYMBOL
  0x00000000     memset  vmlinux EXPORT_SYMBOL
  0x00000000     __sw_hweight64  vmlinux EXPORT_SYMBOL
  0x00000000     __sw_hweight32  vmlinux EXPORT_SYMBOL
  0x00000000     memcpy_mcsafe_unrolled  vmlinux EXPORT_SYMBOL_GPL
  0x00000000     memcpy  vmlinux EXPORT_SYMBOL
  0x00000000     copy_user_enhanced_fast_string  vmlinux EXPORT_SYMBOL
  0x00000000     clear_page      vmlinux EXPORT_SYMBOL
  0x00000000     __put_user_2    vmlinux EXPORT_SYMBOL
  0x00000000     __get_user_2    vmlinux EXPORT_SYMBOL
  0x00000000     copy_page       vmlinux EXPORT_SYMBOL
  0x00000000     copy_user_generic_string        vmlinux EXPORT_SYMBOL
  0x00000000     _copy_to_user   vmlinux EXPORT_SYMBOL
  0x00000000     ___preempt_schedule     vmlinux EXPORT_SYMBOL
  0x00000000     __memmove       vmlinux EXPORT_SYMBOL
  0x00000000     empty_zero_page vmlinux EXPORT_SYMBOL
  0x00000000     __get_user_8    vmlinux EXPORT_SYMBOL
  0x00000000     __put_user_8    vmlinux EXPORT_SYMBOL
  0x00000000     _copy_from_user vmlinux EXPORT_SYMBOL
  0x00000000     native_load_gs_index    vmlinux EXPORT_SYMBOL
  0x00000000     __memset        vmlinux EXPORT_SYMBOL
  0x00000000     ___preempt_schedule_notrace     vmlinux EXPORT_SYMBOL
  0x00000000     __put_user_1    vmlinux EXPORT_SYMBOL
  0x00000000     __get_user_1    vmlinux EXPORT_SYMBOL
  0x00000000     copy_user_generic_unrolled      vmlinux EXPORT_SYMBOL

  If I ignore these and go on to boot the resulting kernel. I am left
with:

  ERROR: Unable to find root device 'UUID=<omitted>'

  I am then dropped to a recovery shell where the keyboard is not
answering.

  The UUID is valid and is the same being used when I boot the HEAD of
the linux
  tree. Prior to failing to find the root device, the kernel prints a
series of
  message for each of the above symbol:

  scsi_mod: no symbol version for <foo>
  scsi_mod: Unknown symbol <foo> (err -22)

  Therefore, I suspect that the missing CRC messages are linked to the
issue.

  I have git bisected this behavior to the patch 784d5699edd.

You can just provide the details and the git bisect result. I think it
should be fine.

OK

quoted

But before that make sure your root device is
detected. If scsi module did not work most likely that your hard disk
is not detected.

So, I am going to look into properly making sure that my hard disk is
detected but
I thought that it being detected by other build was the proof I required. I
am sending
this message from a build more recent than 4.8.0-rc5 and I successfully
booted a
build of the kernel at the commit that directly precede 784d5699edd.

Okay. Provide the git commit id, explain what issue you are facing and
ask for help. That should be fine I think.