[PATCH 0/3] Move kernel mapping outside the linear mapping

From: Alexandre Ghiti
Date: Thu Feb 25 2021 - 03:06:19 EST


I decided to split sv48 support in small series to ease the review.

This patchset pushes the kernel mapping (modules and BPF too) to the last
4GB of the 64bit address space, this allows to:
- implement relocatable kernel (that will come later in another
patchset) that requires to move the kernel mapping out of the linear
mapping to avoid to copy the kernel at a different physical address.
- have a single kernel that is not relocatable (and then that avoids the
performance penalty imposed by PIC kernel) for both sv39 and sv48.

The first patch implements this behaviour, the second patch introduces a
documentation that describes the virtual address space layout of the 64bit
kernel and the last patch is taken from my sv48 series where I simply added
the dump of the modules/kernel/BPF mapping.

I removed the Reviewed-by on the first patch since it changed enough from
last time and deserves a second look.

Alexandre Ghiti (3):
riscv: Move kernel mapping outside of linear mapping
Documentation: riscv: Add documentation that describes the VM layout
riscv: Prepare ptdump for vm layout dynamic addresses

Documentation/riscv/index.rst | 1 +
Documentation/riscv/vm-layout.rst | 61 ++++++++++++++++++++++
arch/riscv/boot/loader.lds.S | 3 +-
arch/riscv/include/asm/page.h | 18 ++++++-
arch/riscv/include/asm/pgtable.h | 37 +++++++++----
arch/riscv/include/asm/set_memory.h | 1 +
arch/riscv/kernel/head.S | 3 +-
arch/riscv/kernel/module.c | 6 +--
arch/riscv/kernel/setup.c | 3 ++
arch/riscv/kernel/vmlinux.lds.S | 3 +-
arch/riscv/mm/fault.c | 13 +++++
arch/riscv/mm/init.c | 81 +++++++++++++++++++++++------
arch/riscv/mm/kasan_init.c | 9 ++++
arch/riscv/mm/physaddr.c | 2 +-
arch/riscv/mm/ptdump.c | 67 +++++++++++++++++++-----
15 files changed, 258 insertions(+), 50 deletions(-)
create mode 100644 Documentation/riscv/vm-layout.rst

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2.20.1