Subject: Re: [PATCH v11 1/7] mm: ksm: Export ksm_madvise()

From: Bharata B Rao <[email-masked]>
Date: Mon, 25 Nov 2019 08:39:58 +0530

On Mon, Nov 25, 2019 at 08:36:25AM +0530, Bharata B Rao wrote:
> On PEF-enabled POWER platforms that support running of secure guests,
> secure pages of the guest are represented by device private pages
> in the host. Such pages needn't participate in KSM merging. This is
> achieved by using ksm_madvise() call which need to be exported
> since KVM PPC can be a kernel module.
> 
> Signed-off-by: Bharata B Rao <[email-masked]>
> Acked-by: Paul Mackerras <[email-masked]>
> Cc: Andrea Arcangeli <[email-masked]>
> Cc: Hugh Dickins <[email-masked]>

Just want to point out that I observe a kernel crash when KSM is
dealing with device private pages. More details about the crash here:

https://lore.kernel.org/linuxppc-dev/[email-masked]/

Regards,
Bharata.