Re: arch/riscv: SV48 patch series questions

From: Palmer Dabbelt
Date: Wed Jun 01 2022 - 23:44:24 EST


On Fri, 27 May 2022 02:37:34 PDT (-0700), leyfoon.tan@xxxxxxxxxxxxxxxx wrote:
Hi Palmer

Alex's "Introduce sv48 support without relocatable kernel" patch series in [1] was partially merged to Linux v5.17. But there are 4 patches are not merged (Patch-10 to 13).

May I know what is the plan for these patches? Will them merged to next v5.19 merging window? Or do you expect any changes for these patches or Alex needs resend with rebase to latest kernel version?

I just saw this as I was digging up Alex's old email to reply to, all but #13 are now on for-next.

Note, we would like to use the Patch-13 in this series.

Is your use case a CPU errata? If so I think we should just go ahead and add that errata via the existing errata mechanism. If you've got some other use case, do you mind elaborating? From that other thread it sounds like a command-line argument is the way to go for folks who want to turn this off more dynamically, but happy to hear if you've got something different in mind.

Patches not merged:
[v3,10/13] riscv: Improve virtual kernel memory layout dump
[v3,11/13] Documentation: riscv: Add sv48 description to VM layout
[v3,12/13] riscv: Initialize thread pointer before calling C functions
[v3,13/13] riscv: Allow user to downgrade to sv39 when hw supports sv48 if !KASAN

[1]: https://patchwork.kernel.org/project/linux-riscv/cover/20211206104657.433304-1-alexandre.ghiti@xxxxxxxxxxxxx/

Thanks.

Regards
Ley Foon