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

Bharata B Rao
2019-11-25T03:21:58Z

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 <bharata@linux.ibm.com>
> Acked-by: Paul Mackerras <paulus@ozlabs.org>
> Cc: Andrea Arcangeli <aarcange@redhat.com>
> Cc: Hugh Dickins <hughd@google.com>

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/20191115141006.GA21409@in.ibm.com/

Regards,
Bharata.