Re: [PATCH v4 0/2] Two-stagged initial page table setup

From: Anup Patel
Date: Mon May 20 2019 - 04:47:31 EST


On Thu, May 2, 2019 at 10:32 AM Anup Patel <Anup.Patel@xxxxxxx> wrote:
>
> This patchset implements two-stagged initial page table setup using fixmap
> to avoid mapping non-existent RAM and also reduce high_memory consumed by
> initial page tables.
>
> The patchset is based on Linux-5.1-rc7 and tested on SiFive Unleashed board
> and QEMU virt machine.
>
> These patches can be found in riscv_setup_vm_v4 branch of
> https//github.com/avpatel/linux.git
>
> Changes since v3:
> - Changed patch series subject.
> - Dropped PATCH1 because it's already merged
> - Dropped PATCH3 because trampoline page table handles a corner case
> for 32bit systems where load address range overlaps kernel virtual
> address range
> - Revamped PATCH for 4K aligned booting into two-stagged initial page
> table setup
>
> Changes since v2:
> - Dropped PATCH2 because we have separate fix for Linux-5.1-rcX
> - Moved PATCH5 to PATCH2
> - Moved PATCH4 to PATCH3
> - The "Booting kernel from any 4KB aligned address" is now PATCH4
>
> Changes since v1:
> - Add kconfig option BOOT_PAGE_ALIGNED to enable 4KB aligned booting
> - Improved initial page table setup code to select best/biggest
> possible mapping size based on load address alignment
> - Added PATCH4 to remove redundant trampoline page table
> - Added PATCH5 to fix memory reservation in setup_bootmem()
>
> Anup Patel (2):
> RISC-V: Fix memory reservation in setup_bootmem()
> RISC-V: Setup initial page tables in two stages
>
> arch/riscv/include/asm/fixmap.h | 5 +
> arch/riscv/include/asm/pgtable-64.h | 5 +
> arch/riscv/include/asm/pgtable.h | 7 +
> arch/riscv/kernel/head.S | 17 +-
> arch/riscv/kernel/setup.c | 4 +-
> arch/riscv/mm/init.c | 327 ++++++++++++++++++++++------
> 6 files changed, 289 insertions(+), 76 deletions(-)
>
> --
> 2.17.1

Hi All,

Any comments on this patchset?

Regards,
Anup