[BUG][linux-next][ppc] kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: __schedule+0x978/0xa80

[Christophe LEROY]

Le 12/10/2018 à 15:23, Abdul Haleem a écrit :
> On Fri, 2018-10-12 at 12:36 +0200, Christophe LEROY wrote:
>>
>> Le 12/10/2018 à 12:31, Abdul Haleem a écrit :
>>> On Fri, 2018-10-12 at 10:08 +0200, Christophe LEROY wrote:
>>>>
>>>> Le 12/10/2018 à 09:48, Abdul Haleem a écrit :
>>>>> On Fri, 2018-10-12 at 13:15 +0530, Abdul Haleem wrote:
>>>>>> Greeting's
>>>>>>
>>>>>> Today's linux-next fails to boot on powerpc bare-metal with this error
>>>>>>
>>>>>> POWER8 performance monitor hardware support registered
>>>>>> rcu: Hierarchical SRCU implementation.
>>>>>> smp: Bringing up secondary CPUs ...
>>>>>> Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: __schedule+0x978/0xa80
>>>>>> CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.19.0-rc7-next-20181010-autotest-autotest #1
>>>>>> Call Trace:
>>>>>> [c000001fed5b3bf0] [c000000000a0ef3c] dump_stack+0xb0/0xf4 (unreliable)
>>>>>> [c000001fed5b3c30] [c0000000000f9d68] panic+0x140/0x308
>>>>>> [c000001fed5b3cc0] [c0000000000f9844] __stack_chk_fail+0x24/0x30
>>>>>> [c000001fed5b3d20] [c000000000a2c3a8] __schedule+0x978/0xa80
>>>>>> [c000001fed5b3e00] [c000000000a2c9b4] schedule_idle+0x34/0x60
>>>>>> [c000001fed5b3e30] [c00000000013d344] do_idle+0x224/0x3d0
>>>>>> [c000001fed5b3ec0] [c00000000013d6e0] cpu_startup_entry+0x30/0x50
>>>>>> [c000001fed5b3ef0] [c000000000047f34] start_secondary+0x4d4/0x520
>>>>>> [c000001fed5b3f90] [c00000000000b370] start_secondary_prolog+0x10/0x14
>>>>>> Rebooting in 10 seconds..
>>>>>>
>>>>>> Machine: Power 8 bare-metal
>>>>>> kernel version: 4.19.0-rc7-next-20181010
>>>>>> gcc version: 4.8.5 20150623
>>>>>> config attach
>>>>>
>>>>> Attaching the kernel config file
>>>>>
>>>>
>>>> # Linux/powerpc 4.11.0-rc4 Kernel Configuration
>>>>
>>>> This is not the correct config file. Can you send the .config ?
>>>
>>> CONFIG_HAVE_STACKPROTECTOR=y
>>> CONFIG_CC_HAS_STACKPROTECTOR_NONE=y
>>> CONFIG_STACKPROTECTOR=y
>>> CONFIG_STACKPROTECTOR_STRONG=y
>>>
>>> ah yes, I have attached the correct config now.
>>
>> Ok,
>>
>> Could you please try and add a call to function boot_init_stack_canary()
>> in function start_secondary() in arch/powerpc/kernel/smp.c just before
>> the call to cpu_startup_entry() ?
> 
> Yes, it works. kernel boots fine with above changes to arch/powerpc/kernel/smp.c
> 

Thanks,

Could you please test the patch I just sent ?
I that patch, I initialises the stack canary when preparing the idle 
tasks rather than doing it at its startup.

Christophe