From:   Alexandre Ghiti <alexghiti@rivosinc.com>
To:     Jonathan Corbet <corbet@lwn.net>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Conor Dooley <conor@kernel.org>,
        Ard Biesheuvel <ardb@kernel.org>, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org
Cc:     Alexandre Ghiti <alexghiti@rivosinc.com>
Subject: [PATCH v4 0/1] riscv: Allow to downgrade paging mode from the command line
Date:   Tue, 31 Jan 2023 16:11:14 +0100
Message-Id: <20230131151115.1972740-1-alexghiti@rivosinc.com>
MIME-Version: 1.0
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This new version gets rid of the limitation that prevented KASAN kernels
to use the newly introduced parameters.

While looking into KASLR, I fell onto commit aacd149b6238 ("arm64: head:
avoid relocating the kernel twice for KASLR"): it allows to use the fdt
functions very early in the boot process with KASAN enabled by simply
compiling a new version of those functions without instrumentation.

I had to change the handling of the command line parsing to make the
code self-contained in kernel/pi/cmd_early.c to avoid calling too many
__pi prefixed functions from outside this file.

I'll use this approach like arm64 to handle the extraction of the random
seedi from the device tree for KASLR.

@Ard: I copied the "pi" name but I have to admit I don't know what it
means.

Alexandre Ghiti (1):
  riscv: Allow to downgrade paging mode from the command line

 .../admin-guide/kernel-parameters.txt         |  5 +-
 arch/riscv/kernel/Makefile                    |  2 +
 arch/riscv/kernel/pi/Makefile                 | 34 ++++++++++++
 arch/riscv/kernel/pi/cmdline_early.c          | 52 +++++++++++++++++++
 arch/riscv/lib/memcpy.S                       |  2 +
 arch/riscv/lib/memmove.S                      |  2 +
 arch/riscv/mm/init.c                          | 36 ++++++++++---
 7 files changed, 126 insertions(+), 7 deletions(-)
 create mode 100644 arch/riscv/kernel/pi/Makefile
 create mode 100644 arch/riscv/kernel/pi/cmdline_early.c

-- 
2.37.2