Re: [PATCH AUTOSEL 6.3 06/11] of: fdt: Scan /memreserve/ last

[Sasha Levin]

On Mon, May 15, 2023 at 09:21:04PM +0100, Conor Dooley wrote:
> Hey Sasha,
>
> On Thu, May 11, 2023 at 03:37:49PM -0400, Sasha Levin wrote:
> > From: Lucas Tanure <tanure@xxxxxxxxx>
> >
> > [ Upstream commit b413281876292de44ae84e9a9ce9d62e47f266e9 ]
> >
> > Change the scanning /memreserve/ and /reserved-memory node order to fix
> > Kernel panic on Khadas Vim3 Board.
> >
> > If /memreserve/ goes first, the memory is reserved, but nomap can't be
> > applied to the region. So the memory won't be used by Linux, but it is
> > still present in the linear map as normal memory, which allows
> > speculation. Legitimate access to adjacent pages will cause the CPU
> > to end up prefetching into them leading to Kernel panic.
> >
> > So /reserved-memory node should go first, as it has a more updated
> > description of the memory regions and can apply flags, like nomap.
> >
> > Link: https://lore.kernel.org/all/CAJX_Q+1Tjc+-TjZ6JW9X0NxEdFe=82a9626yL63j7uVD4LpxEA@xxxxxxxxxxxxxx/
> > Signed-off-by: Lucas Tanure <tanure@xxxxxxxxx>
> > Link: https://lore.kernel.org/r/20230424113846.46382-1-tanure@xxxxxxxxx
> > Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
> > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
>
> Rob requested that this patch (and it's bretheren in other AUTOSEL
> series) not be backported immediately:
> | Going to let this sit in linux-next for a bit. I also didn't tag for
> | stable kernels. I want it to get some exposure in mainline at least for
> | a few -rc releases rather than getting backported right away. Please
> | help ensure that happens if you see stable review emails. I'm going to
> | be offline most of the next month.
> https://lore.kernel.org/linux-devicetree/168262872454.3491083.6407810340850053636.robh@xxxxxxxxxx/
>
> Perhaps delaying it for another couple of weeks, since we have only just
> had -rc2, is a good idead?

I'll drop it, let me know when you want it included back. Thanks!

--
Thanks,
Sasha