Re: [RFC PATCH V2] kvm: arm64: export memory error recovery capability to user space

[Peter Maydell]

On Mon, 13 May 2019 at 07:32, Dongjiu Geng <gengdongjiu@xxxxxxxxxx> wrote:
>
> When user space do memory recovery, it will check whether KVM and
> guest support the error recovery, only when both of them support,
> user space will do the error recovery. This patch exports this
> capability of KVM to user space.
>
> Cc: Peter Maydell <peter.maydell@xxxxxxxxxx>
> Signed-off-by: Dongjiu Geng <gengdongjiu@xxxxxxxxxx>
> ---
> v1->v2:
> 1. check whether host support memory failure instead of RAS capability
>    https://patchwork.kernel.org/patch/10730827/
>
> v1:
> 1. User space needs to check this capability of host is suggested by Peter[1],
> this patch as RFC tag because user space patches are still under review,
> so this kernel patch is firstly sent out for review.
>
> [1]: https://patchwork.codeaurora.org/patch/652261/
> ---

I thought the conclusion of the thread on the v1 patch was that
userspace doesn't need to specifically ask the host kernel if
it has support for this -- if it does not, then the host kernel
will just never deliver userspace any SIGBUS with MCEERR code,
which is fine. Or am I still confused?

thanks
-- PMM