diff mbox series

[mm,2/2] Revert "kasan, arm64: don't allow SW_TAGS with ARM64_MTE"

Message ID a6287f2b9836ba88132341766d85810096e27b8e.1607537948.git.andreyknvl@google.com (mailing list archive)
State New, archived
Headers show
Series kasan: a few HW_TAGS fixes | expand

Commit Message

Andrey Konovalov Dec. 9, 2020, 6:24 p.m. UTC
This reverts "kasan, arm64: don't allow SW_TAGS with ARM64_MTE".

In earlier versions on the hardware tag-based KASAN patchset in-kernel
MTE used to be always enabled when CONFIG_ARM64_MTE is on. This caused
conflicts with the software tag-based KASAN mode.

This is no logner the case: in-kernel MTE is never enabled unless the
CONFIG_KASAN_HW_TAGS is enabled, so there are no more conflicts with
CONFIG_KASAN_SW_TAGS.

Allow CONFIG_KASAN_SW_TAGS to be enabled even when CONFIG_ARM64_MTE is
enabled.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 arch/arm64/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Marco Elver Dec. 9, 2020, 6:51 p.m. UTC | #1
On Wed, 9 Dec 2020 at 19:24, Andrey Konovalov <andreyknvl@google.com> wrote:
>
> This reverts "kasan, arm64: don't allow SW_TAGS with ARM64_MTE".
>
> In earlier versions on the hardware tag-based KASAN patchset in-kernel
> MTE used to be always enabled when CONFIG_ARM64_MTE is on. This caused
> conflicts with the software tag-based KASAN mode.
>
> This is no logner the case: in-kernel MTE is never enabled unless the
> CONFIG_KASAN_HW_TAGS is enabled, so there are no more conflicts with
> CONFIG_KASAN_SW_TAGS.
>
> Allow CONFIG_KASAN_SW_TAGS to be enabled even when CONFIG_ARM64_MTE is
> enabled.
>
> Signed-off-by: Andrey Konovalov <andreyknvl@google.com>

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


> ---
>  arch/arm64/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 6fefab9041d8..62a7668976a2 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -135,7 +135,7 @@ config ARM64
>         select HAVE_ARCH_JUMP_LABEL
>         select HAVE_ARCH_JUMP_LABEL_RELATIVE
>         select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
> -       select HAVE_ARCH_KASAN_SW_TAGS if (HAVE_ARCH_KASAN && !ARM64_MTE)
> +       select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
>         select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE)
>         select HAVE_ARCH_KFENCE
>         select HAVE_ARCH_KGDB
> --
> 2.29.2.576.ga3fc446d84-goog
>
Andrew Morton Dec. 9, 2020, 11:22 p.m. UTC | #2
On Wed, 9 Dec 2020 19:51:05 +0100 Marco Elver <elver@google.com> wrote:

> > This is no logner the case: in-kernel MTE is never enabled unless the
> > CONFIG_KASAN_HW_TAGS is enabled, so there are no more conflicts with
> > CONFIG_KASAN_SW_TAGS.
> >
> > Allow CONFIG_KASAN_SW_TAGS to be enabled even when CONFIG_ARM64_MTE is
> > enabled.
> >
> > Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> 
> Reviewed-by: Marco Elver <elver@google.com>

Thanks.  I simply dropped
kasan-arm64-dont-allow-sw_tags-with-arm64_mte.patch.
diff mbox series

Patch

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 6fefab9041d8..62a7668976a2 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -135,7 +135,7 @@  config ARM64
 	select HAVE_ARCH_JUMP_LABEL
 	select HAVE_ARCH_JUMP_LABEL_RELATIVE
 	select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
-	select HAVE_ARCH_KASAN_SW_TAGS if (HAVE_ARCH_KASAN && !ARM64_MTE)
+	select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
 	select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE)
 	select HAVE_ARCH_KFENCE
 	select HAVE_ARCH_KGDB