X86 4.8 kernel boot questions

[Tracy Smith, CEO]

Hi All,

The production board I'm using doesn't have a JTAG available,
upgrading to 4.8 from 4.1,.and need to understand why Linux 4.8.3
doesn't boot on a x86_64 corei7-64. Boots with no issues with 4.1.

Hangs at the last message of u-boot, the typical "Starting kernel."
The bootcmd and arguments are  given below.

I see a fault FFS and a message indicating the image didn't load after failover.

1) How can I verify if the kernel image was loaded?

2) What is this FFS fault? Where do I find this.

3) Has the bootargs or bootcmd changed between 4.1 and 4.8.3?

4) If the boot cmd/arg has changed, what should the boot cmd/arg be
for 4.8.3 to boot on x86_64 corei7-64?

Initial RAM disk at linear address 0x20000000, size 11638378 bytes

Kernel command line: "BOOT_IMAGE=/imgx/bzImage LABEL=BOOT
root=/dev/ram0 imgmnt=/media/sda2 imgdir=imgx img=image.rootfs
rootdelay=2 slub_debug=F console=ttyS1,115200  bootcount=1
bootcount_addr=0xa4000  acpi_enforce_resources=lax pram_size=0x800000
pram_addr=10000000 pram_loc=ddr crashkernel=128M
memmap=0x800000$0x10000000  "EFI table at 683392c0, mmap 68339300,
mmap size 4c0, version 1, descr. size 0x30

Starting kernel ...

Timer summary in microseconds:

       Mark    Elapsed  Stage
          0          0  reset
          1          1  board_init_r
        105        104  board_init_f
 10,180,048 10,179,943  id=64
 10,221,985     41,937  id=65
 10,356,645    134,660  main_loop
 12,366,521  2,009,876  usb_start
 18,747,284  6,380,763  start_kernel
Accumulated time:
            10,162,689  ahci


On a 4.1.26-yocto-standard #1 SMP it boots with no issues.  Basically
same .config used in both cases except for anything deprecated between
4.1 and 4.8.3.

root@:~# cat /proc/cmdline
BOOT_IMAGE=/imgy/bzImage LABEL=BOOT root=/dev/ram0 imgmnt=/media/sda2
imgdir=imgy img=image.rootfs rootdelay=2 slub_debug=F
console=ttyS1,115200 fault=FFS bootcount=3 bootcount_addr=0xa4000
acpi_enforce_resources=lax pram_size=0x800000 pram_addr=10000000
pram_loc=ddr crashkernel=128M memmap=0x800000$0x10000000

root@CLX3001:~# cat /proc/consoles
ttyS1                -W- (EC p a)    4:65
netcon0              -W- (E     )