Re: [RFC PATCH 4/5] mm, memory_hotplug: print reason for the offlining failure

[Anshuman Khandual]

On 11/07/2018 03:48 PM, Michal Hocko wrote:
> From: Michal Hocko <mhocko@xxxxxxxx>
> 
> The memory offlining failure reporting is inconsistent and insufficient.
> Some error paths simply do not report the failure to the log at all.
> When we do report there are no details about the reason of the failure
> and there are several of them which makes memory offlining failures
> hard to debug.
> 
> Make sure that the
> 	memory offlining [mem %#010llx-%#010llx] failed
> message is printed for all failures and also provide a short textual
> reason for the failure e.g.
> 
> [ 1984.506184] rac1 kernel: memory offlining [mem 0x82600000000-0x8267fffffff] failed due to signal backoff
> 
> this tells us that the offlining has failed because of a signal pending
> aka user intervention.
> 
> Signed-off-by: Michal Hocko <mhocko@xxxxxxxx>

It might help to enumerate these failure reason strings and use macros.