Re: [LKP] [x86] 811565123a: BUG: kernel hang in early-boot stage, last printk: Probing EDD (edd=off to disable)... ok

[Ye Xiaolong]

On 10/14, Ye Xiaolong wrote:
>On 10/13, Andi Kleen wrote:
>>Andi Kleen <andi@xxxxxxxxxxxxxx> writes:
>>
>>Any comments on this?
>>
>>I still cannot reproduce the failure unfortunately.
>>
>
>Btw, you can try below commands to reproduce the error on your local
>host, they will download the necessary images and run QEMU:
>
>       git clone git://git.kernel.org/pub/scm/linux/kernel/git/wfg/lkp-tests.git
>       cd lkp-tests
>       bin/lkp qemu -k KERNEL job-script  # job-script is attached in the original report email

Results show this hang may be related to gcc version, with gcc version
4.8.4 (Ubuntu 4.8.4-2ubuntu1~14.04.3), kernel could boot without early
hang, but if kernel was built with gcc version 6.2.0 20160901 (Debian
6.2.0-3), it will stuck in the early stage:

early console in setup code
Probing EDD (edd=off to disable)... ok


gdb output as below:

$ gdb -ex "target remote localhost:1234" vmlinux 
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Reading symbols from vmlinux...done.
Remote debugging using localhost:1234
0x048a34d9 in ?? ()
(gdb) bt
#0  0x048a34d9 in ?? ()
#1  0x00000000 in ?? ()
(gdb) 


Thanks,
Xiaolong
>
>Thanks,
>Xiaolong
>>
>>> Could you do two tests for me:
>>>
>>> - Enable CONFIG_MICROCODE_INTEL and see if it boots then
>>>
>>> - Add CONFIG_DEBUG_INFO to the config.
>>> Add -s to the qemu command line and boot again. Then when it hangs 
>>> connect gdb to see where it hangs
>>>
>>> gdb -ex "target remote localhost:1234" vmlinux
>>> bt
>>>
>>> <show output>
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