[Bug 1508893] Re: TFTP timeout on ARM64 hw when booting from grub that was PXE loaded

[Raghuram Kota]

Ming Lei  has identified that this issue is fixed with the following
upstream grub patch:

commit 49426e9fd2e562c73a4f1206f32eff9e424a1a73
Author: Andrei Borzenkov <arvidjaar at gmail.com>
Date: Thu May 7 20:37:17 2015 +0300

    efinet: open Simple Network Protocol exclusively

The next step is to backport this patch into Wily and probably also
Trusty.

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to grub2 in Ubuntu.
https://bugs.launchpad.net/bugs/1508893

Title:
  TFTP timeout on ARM64 hw when booting from grub that was  PXE loaded

Status in grub2 package in Ubuntu:
  New

Bug description:
  This issue was discovered  with Ubuntu Wily (15.10) on a currently in
  development ARM64 HW.

  When loading kernel via tftp in grub on this hardware, the system
  stops receiving new packets (times out )  after receiving initial few
  tens of tftp data packets , which then causes kernel load failure.

  Running tcpdump before loading kernel in grub menu shows timeouts
  occurring,  as captured in the below log  :

        http://kernel.ubuntu.com/~ming/grub/apm.tcpdump

  Following are the  detailed reproduction steps :

  1) setup PXE boot entry in UEFI(no any parameter to grub)
  2) build one grub from upstream (and/or Wily)  and put it in PXE&TFTP server
  3) setup grub config, suppose the shape is like below:
       menuentry 'Install for arm64' {
            linux /ubuntu-installer/arm64/Image --- console=ttyS0,115200
            initrd /ubuntu-installer/arm64/initrd.gz
      }
  4) start PXE booting in UEFI
  5) grub prompt is coming
  6) select 'Install for arm64' menu item and press 'enter' to start
  loading kernel
  7) then hangs inside loading kernel

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1508893/+subscriptions