[PATCH 0/2] Restrict address space for sv39,sv48,sv57

[Charlie Jenkins]

I see it in patchwork here:
https://patchwork.kernel.org/project/linux-mm/cover/20230626183611.40479-1-charlie@rivosinc.com/.

On Tue, Jun 27, 2023 at 1:44 PM Charles Jenkins <charlie at rivosinc.com> wrote:
>
> I talked to Atish, he's not sure what's going on here either. I am going
> to add him to the CC list.
>
> On Tue, Jun 27, 2023 at 11:24 AM Conor Dooley <conor at kernel.org> wrote:
>
> > Hey Charlie,
> >
> > On Mon, Jun 26, 2023 at 11:36:02AM -0700, Charlie Jenkins wrote:
> > > Make sv39 the default address space for mmap as some applications
> > > currently depend on this assumption. The RISC-V specification enforces
> > > that bits outside of the virtual address range are not used, so
> > > restricting the size of the default address space as such should be
> > > temporary. A hint address passed to mmap will cause the largest address
> > > space that fits entirely into the hint to be used. If the hint is less
> > > than or equal to 1<<38, a 39-bit address will be used. After an address
> > > space is completely full, the next smallest address space will be used.
> > >
> > > Documentation is also added to the RISC-V virtual memory section to
> > explain
> > > these changes.
> >
> > I don't know what went wrong here, but this never ended up in patchwork
> > for some reason, although it has appeared on lore. That seems to be via
> > the docs mailing list, rather than linux-riscv. Could you speak to Atish
> > and see if he knows what went wrong?
> >
> > Cheers,
> > Conor.
> >
> > >
> > > Charlie Jenkins (2):
> > >   RISC-V: mm: Restrict address space for sv39,sv48,sv57
> > >   RISC-V: mm: Update documentation and include test
> > >
> > >  Documentation/riscv/vm-layout.rst             | 20 ++++++++
> > >  arch/riscv/include/asm/elf.h                  |  2 +-
> > >  arch/riscv/include/asm/pgtable.h              | 21 ++++++--
> > >  arch/riscv/include/asm/processor.h            | 41 +++++++++++++---
> > >  tools/testing/selftests/riscv/Makefile        |  2 +-
> > >  tools/testing/selftests/riscv/mm/Makefile     | 22 +++++++++
> > >  .../selftests/riscv/mm/testcases/mmap.c       | 49 +++++++++++++++++++
> > >  7 files changed, 144 insertions(+), 13 deletions(-)
> > >  create mode 100644 tools/testing/selftests/riscv/mm/Makefile
> > >  create mode 100644 tools/testing/selftests/riscv/mm/testcases/mmap.c
> > >
> > >
> > > base-commit: eef509789cecdce895020682192d32e8bac790e8
> > > --
> > > 2.34.1
> > >
> >