Re: [PATCH v2 2/2] mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two)

From: Christopher Lameter
Date: Wed Sep 04 2019 - 15:31:35 EST

On Tue, 3 Sep 2019, Matthew Wilcox wrote

> > Its enabled in all full debug session as far as I know. Fedora for
> > example has been running this for ages to find breakage in device drivers
> > etc etc.
> Are you telling me nobody uses the ramdisk driver on fedora? Because
> that's one of the affected drivers.

How do I know? I dont run these tests.

> > decade now) I am having a hard time believing the stories of great
> > breakage here. These drivers were not tested with debugging on before?
> > Never ran with a debug kernel?
> Whatever is being done is clearly not enough to trigger the bug. So how
> about it? Create an option to slab/slub to always return misaligned
> memory.

It already exists

Add "slub_debug" on the kernel command line.