Re: ext4 corruption on alpha with 4.20.0-09062-gd8372ba8ce28

Jan Kara
2019-02-20T09:48:21Z

On Wed 20-02-19 08:31:05, Meelis Roos wrote:
> > Could
> > https://lore.kernel.org/linux-mm/20190219123212.29838-1-larper@axis.com/T/#u
> > be relevant?
>
> Tried it, still broken.

OK, I didn't put too much hope into this patch as you see filesystem
metadata corruption so icache/dcache coherency issues seemed unlikely.
Still good that you've tried so that we are sure.

> I wrote:
>
> > But my kernel config had memory compaction (that turned on page migration) and
> > bounce buffers. I do not remember why I found them necessary but I will try
> > without them.
>
> First, I found out that both the problematic alphas had memory compaction and
> page migration and bounce buffers turned on, and working alphas had them off.
>
> Next, turing off these options makes the problematic alphas work.

OK, thanks for testing! Can you narrow down whether the problem is due to
CONFIG_BOUNCE or CONFIG_MIGRATION + CONFIG_COMPACTION? These are two
completely different things so knowing where to look will help. Thanks!

Honza
--
Jan Kara <jack@suse.com>
SUSE Labs, CR