Re: [gentoo-user] Problems booting vanilla kernel 4.1.x

[Alexander Kapshuk <alexander.kapshuk@gmail.com>]

On Sat, Aug 29, 2015 at 3:09 PM, Peter Weilbacher
<newsspam@weilbacher.org> wrote:
> On Tue, 25 Aug 2015, Alexander Kapshuk wrote:
>
>> I've never experienced this particular kernel trouble myself, so I'm
>> not sure if my input would be of much help.
>> Here's what the kernel documentation has to say about this kind of issue:
>>
>> /usr/src/linux/Documentation/RCU/stallwarn.txt:29,33
> [...]
>> Have a look for possibly stack traces in these log files:
>> /var/log/{messages,dmesg}.
>>
>> Hopefully, someone else with more kernel debugging experience will
>> have something more substantial to say about this.
>
> Thanks for the reply, Alex. I had googled for those messages, too, and
> had found that RCU info. Unfortunately, I have no idea what to do with
> it, since it stops right at the booting stage, right before init starts,
> so before I can do anything interactive.
>
> I have posted a message to the LKML, maybe someone there has a hint.
> (The machine is old and rarely used, but I would still like to run the
> newest software because it is connected to the net.)
>
>    Peter.
>

Hope you do get this sorted.

You probably did look into this yourself, but did you double-check
your /etc/lilo.conf? Is everything fine there?

Here are my RCU kernel config options. What do yours look like?
% uname -r
4.1.6-vanilla
% grep RCU .config
# RCU Subsystem
CONFIG_TREE_RCU=y
CONFIG_SRCU=y
# CONFIG_TASKS_RCU is not set
CONFIG_RCU_STALL_COMMON=y
CONFIG_RCU_FANOUT=32
CONFIG_RCU_FANOUT_LEAF=16
# CONFIG_RCU_FANOUT_EXACT is not set
# CONFIG_RCU_FAST_NO_HZ is not set
# CONFIG_TREE_RCU_TRACE is not set
CONFIG_RCU_KTHREAD_PRIO=0
# CONFIG_RCU_NOCB_CPU is not set
# CONFIG_RCU_EXPEDITE_BOOT is not set
# RCU Debugging
# CONFIG_PROVE_RCU is not set
# CONFIG_SPARSE_RCU_POINTER is not set
# CONFIG_RCU_TORTURE_TEST is not set
CONFIG_RCU_CPU_STALL_TIMEOUT=21
# CONFIG_RCU_CPU_STALL_INFO is not set
# CONFIG_RCU_TRACE is not set