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References: <20220211162142.2402-1-nemanja.rakovic@syrmia.com>
In-Reply-To: <20220211162142.2402-1-nemanja.rakovic@syrmia.com>
From:   Marco Elver <elver@google.com>
Date:   Fri, 11 Feb 2022 18:06:04 +0100
Message-ID: <CANpmjNO75cTC24vHUNrfR5VSv9jsgqcJ14RyyQos+1mpx599Cw@mail.gmail.com>
Subject: Re: [PATCH V2] mips: Enable KCSAN
To:     Nemanja Rakovic <nemanja.rakovic@syrmia.com>
Cc:     Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        linux-kernel@vger.kernel.org, dragan.mladjenovic@syrmia.com
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On Fri, 11 Feb 2022 at 17:22, Nemanja Rakovic
<nemanja.rakovic@syrmia.com> wrote:
>
> This patch enables KCSAN for the 64-bit version. Updated rules
> for the incompatible compilation units (vdso, boot/compressed).
>
> Signed-off-by: Nemanja Rakovic <nemanja.rakovic@syrmia.com>

Acked-by: Marco Elver <elver@google.com>


> ---
>  arch/mips/Kconfig                  | 1 +
>  arch/mips/boot/compressed/Makefile | 1 +
>  arch/mips/vdso/Makefile            | 3 +++
>  3 files changed, 5 insertions(+)
>
> Changes were tested on qemu (qemu-system-mips64el) with the
> 64r6el_defconfig configuration and KCSAN enabled.
>
> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
> index 058446f01487..651d4fe355da 100644
> --- a/arch/mips/Kconfig
> +++ b/arch/mips/Kconfig
> @@ -101,6 +101,7 @@ config MIPS
>         select TRACE_IRQFLAGS_SUPPORT
>         select VIRT_TO_BUS
>         select ARCH_HAS_ELFCORE_COMPAT
> +       select HAVE_ARCH_KCSAN if 64BIT
>
>  config MIPS_FIXUP_BIGPHYS_ADDR
>         bool
> diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile
> index 5a15d51e8884..6cc28173bee8 100644
> --- a/arch/mips/boot/compressed/Makefile
> +++ b/arch/mips/boot/compressed/Makefile
> @@ -38,6 +38,7 @@ KBUILD_AFLAGS := $(KBUILD_AFLAGS) -D__ASSEMBLY__ \
>  KCOV_INSTRUMENT                := n
>  GCOV_PROFILE := n
>  UBSAN_SANITIZE := n
> +KCSAN_SANITIZE                 := n
>
>  # decompressor objects (linked with vmlinuz)
>  vmlinuzobjs-y := $(obj)/head.o $(obj)/decompress.o $(obj)/string.o $(obj)/bswapsi.o
> diff --git a/arch/mips/vdso/Makefile b/arch/mips/vdso/Makefile
> index d65f55f67e19..f72658b3a53f 100644
> --- a/arch/mips/vdso/Makefile
> +++ b/arch/mips/vdso/Makefile
> @@ -1,6 +1,9 @@
>  # SPDX-License-Identifier: GPL-2.0
>  # Objects to go into the VDSO.
>
> +# Sanitizer runtimes are unavailable and cannot be linked here.
> + KCSAN_SANITIZE                        := n
> +
>  # Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
>  # the inclusion of generic Makefile.
>  ARCH_REL_TYPE_ABS := R_MIPS_JUMP_SLOT|R_MIPS_GLOB_DAT
> --
> 2.17.1
>