[PATCH] [SRU] [xenial/master-next] [Config] arm64: disable BPF_JIT_ALWAYS_ON

[Paolo Pisati]

BugLink: https://bugs.launchpad.net/bugs/1763644

[Impact]

The Ubuntu-4.4.0-120.144 kernel (now in -proposed) fails to boot on all arm64
hardware: no console output or any other sign of activity, the system freezes
right after the bootloader loads vmlinuz, and jumps to it.

We first experienced it on the snapdragon kernel snap in -beta (dragonboard
410c) but the bug is arm64 generic, and it affects all the arm64 hardware: a
thunderx board shows the same exact symptoms.

The regression came down as part of the 4.4.115 stable update ("79e83d1 bpf:
introduce BPF_JIT_ALWAYS_ON config") and enabled this option that crashes the
arm64 kernel on boot.

[How to test]

Apply the attached patch, recompile, install and boot.

[Regression potential]

None, since the kernel already fails to boot.

I attached the config change for generic and snapdragon.

Paolo Pisati (1):
  UBUNTU: [Config] arm64: disable BPF_JIT_ALWAYS_ON

 debian.master/config/amd64/config.common.amd64 | 1 +
 debian.master/config/arm64/config.common.arm64 | 1 +
 debian.master/config/config.common.ubuntu      | 1 -
 debian.master/config/s390x/config.common.s390x | 1 +
 4 files changed, 3 insertions(+), 1 deletion(-)

-- 
2.7.4