Re: [PATCH v2] mm/slub: introduce SLAB_WARN_ON_ERROR

From: Miles Chen
Date: Mon Jan 28 2019 - 22:46:10 EST


On Mon, 2019-01-28 at 17:41 -0800, David Rientjes wrote:
> On Thu, 24 Jan 2019, miles.chen@xxxxxxxxxxxx wrote:
>
> > From: Miles Chen <miles.chen@xxxxxxxxxxxx>
> >
> > When debugging slab errors in slub.c, sometimes we have to trigger
> > a panic in order to get the coredump file. Add a debug option
> > SLAB_WARN_ON_ERROR to toggle WARN_ON() when the option is set.
> >
>
> Wouldn't it be better to enable/disable this for all slab caches instead
> of individual caches at runtime? I'm not sure excluding some caches
> because you know they'll WARN and trigger panic_on_warn unnecessarily is
> valid since it could be enabled for that cache as well through this
> interface.

We can enable this option only for specific slab(s).
e.g., slub_debug=W,dentry
or
enable this option for all slabs
e.g., slub_debug=W