Re: [RFC][PATCH v2 2/3] Hold multiple logs

From: Don Zickus
Date: Thu Jul 19 2012 - 23:03:36 EST

On Fri, Jul 20, 2012 at 12:39:24AM +0000, Seiji Aguchi wrote:
> Thank you for describing this in detail.
> > Yes - if the OOPs is instrumental in the path leading to the hang/panic - then the OOPS is the first place to look for the root cause of
> > the problem. But it will be a case by case analysis.
> > Sometimes the OOPS might be unconnected. If possible we'd like to log more information to allow detective work to decide whether
> > there is a connection. But as I mentioned above there are severe limits to how much better things are by storing more information.
> I understand the reason why you think 3 or 4 logs are reasonable.
> There are some cases 2nd or 3rd oops is critical....
> I have some enterprise customers who are sensitive for a software failure and specify panic_on_oops=1.
> In this case, they don't need 3,4 logs. 2 logs are enough.
> So, kernel parameter should be as follows.
> Log_num =1
> - For users who want to hold just one log.
> Log_num=2
> - For users who can handle multiple logs and 1st oops is concerned. (by specifying panic_on_oops=1)
> Log_num=3,4
> - for users who care about 2nd or 3rd oops.
> Log_num=5 or more
> Invalid value.

What is the harm of not using this and just letting the number be infinite
(or until EFI runs out of space)? Is it a big deal if extra failures are

The hope would be a daemon would clear the old logs out and you never run
out of space.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at