Re: [PATCH v4 2/2] RISC-V: Implement sparsemem

From: Greentime Hu
Date: Thu Aug 15 2019 - 22:07:25 EST


On Fri, Aug 16, 2019 at 12:20 AM Logan Gunthorpe <logang@xxxxxxxxxxxx> wrote:
>
>
>
> On 2019-08-15 3:31 a.m., Greentime Hu wrote:
> > Hi Logan,
> >
> > On Thu, Aug 15, 2019 at 6:21 AM Logan Gunthorpe <logang@xxxxxxxxxxxx> wrote:
> >>
> >> Hey,
> >>
> >> On 2019-08-14 7:35 a.m., Greentime Hu wrote:
> >>> How about this fix? Not sure if it is good for everyone.
> >>
> >> I applied your fix to the patch and it seems ok. But it doesn't seem to
> >> work on a recent version of the kernel. Have you got it working on v5.3?
> >> It seems the following patch breaks things:
> >>
> >> 671f9a3e2e24 ("RISC-V: Setup initial page tables in two stages")
> >>
> >> I don't really have time right now to debug this any further.
> >>
> >
> > I just tried v5.3-rc4 and it failed. I try to debug this case.
> > I found it failed might be because of an unmapped virtual address is used
> > in memblocks_present() -> memblock_alloc ().
> >
> > In this commit 671f9a3e2e24 ("RISC-V: Setup initial page tables in two
> > stages"), it finishes all the VA/PA mapping after setup_vm_final() is
> > called.
> > So we have to call memblocks_present() and sparse_init() right after
> > setup_vm_final().
> >
> > Here is my patch and I tested with memory-with-hole.
> > It can boot normally in Unleashed board after applying this patch.
>
> Great, thanks! I'll roll this into my patch and send v5 out when I have
> a moment. Can I add your Signed-off-by for the bits you've contributed
> to give you credit for your work?

Sure. Please use my Signed-off-by: Greentime Hu <greentime.hu@xxxxxxxxxx>