[PATCH v2] glibc: Enable memory tagging for aarch64

[PATCH v2] glibc: Enable memory tagging for aarch64

[Khem Raj]

Glibc on aarch64 has a memory tagging option that can be enabled
via GLIBC_TUNABLES="glibc.mem.tagging=$SOMETHING" when glibc
is built with memory tagging support and the kernel/HW supports
MTE. There should be no side effects unless the user turns it
on with approprate HW support

Linux 5.4 headers and binutils 2.33.1 or newer is needed.

Signed-off-by: Khem Raj <raj.khem@gmail.com>
---
v2: Rebased

 meta/recipes-core/glibc/glibc_2.33.bb | 1 +
 1 file changed, 1 insertion(+)

diff --git a/meta/recipes-core/glibc/glibc_2.33.bb b/meta/recipes-core/glibc/glibc_2.33.bb
index 75a1f36d6b..c805755bb9 100644
--- a/meta/recipes-core/glibc/glibc_2.33.bb
+++ b/meta/recipes-core/glibc/glibc_2.33.bb
@@ -95,6 +95,7 @@ EXTRA_OECONF += "${@get_libc_fpu_setting(bb, d)}"
 
 EXTRA_OECONF_append_x86 = " --enable-cet"
 EXTRA_OECONF_append_x86-64 = " --enable-cet"
+EXTRA_OECONF_append_aarch64 = " --enable-memory-tagging"
 
 PACKAGECONFIG ??= "nscd"
 PACKAGECONFIG[nscd] = "--enable-nscd,--disable-nscd"
-- 
2.31.1

Re: [OE-core] [PATCH v2] glibc: Enable memory tagging for aarch64

[Ross Burton]

+1 from me, I had the same patch locally that I was about to send :)

I do wonder if we should start using that PACKAGECONFIG for these
tunables, as on non-MTE hardware there is an overhead (albeit small).

Ross

On Sun, 23 May 2021 at 15:45, Khem Raj <raj.khem@gmail.com> wrote:
>
> Glibc on aarch64 has a memory tagging option that can be enabled
> via GLIBC_TUNABLES="glibc.mem.tagging=$SOMETHING" when glibc
> is built with memory tagging support and the kernel/HW supports
> MTE. There should be no side effects unless the user turns it
> on with approprate HW support
>
> Linux 5.4 headers and binutils 2.33.1 or newer is needed.
>
> Signed-off-by: Khem Raj <raj.khem@gmail.com>
> ---
> v2: Rebased
>
>  meta/recipes-core/glibc/glibc_2.33.bb | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/meta/recipes-core/glibc/glibc_2.33.bb b/meta/recipes-core/glibc/glibc_2.33.bb
> index 75a1f36d6b..c805755bb9 100644
> --- a/meta/recipes-core/glibc/glibc_2.33.bb
> +++ b/meta/recipes-core/glibc/glibc_2.33.bb
> @@ -95,6 +95,7 @@ EXTRA_OECONF += "${@get_libc_fpu_setting(bb, d)}"
>
>  EXTRA_OECONF_append_x86 = " --enable-cet"
>  EXTRA_OECONF_append_x86-64 = " --enable-cet"
> +EXTRA_OECONF_append_aarch64 = " --enable-memory-tagging"
>
>  PACKAGECONFIG ??= "nscd"
>  PACKAGECONFIG[nscd] = "--enable-nscd,--disable-nscd"
> --
> 2.31.1
>
>
> 
>

Re: [OE-core] [PATCH v2] glibc: Enable memory tagging for aarch64

[Khem Raj]

On Mon, May 24, 2021 at 3:14 AM Ross Burton <ross@burtonini.com> wrote:
>
> +1 from me, I had the same patch locally that I was about to send :)
>
> I do wonder if we should start using that PACKAGECONFIG for these
> tunables, as on non-MTE hardware there is an overhead (albeit small).
>

for aarch64 it would be better to stay with common glibc for wide
subset if we can

> Ross
>
> On Sun, 23 May 2021 at 15:45, Khem Raj <raj.khem@gmail.com> wrote:
> >
> > Glibc on aarch64 has a memory tagging option that can be enabled
> > via GLIBC_TUNABLES="glibc.mem.tagging=$SOMETHING" when glibc
> > is built with memory tagging support and the kernel/HW supports
> > MTE. There should be no side effects unless the user turns it
> > on with approprate HW support
> >
> > Linux 5.4 headers and binutils 2.33.1 or newer is needed.
> >
> > Signed-off-by: Khem Raj <raj.khem@gmail.com>
> > ---
> > v2: Rebased
> >
> >  meta/recipes-core/glibc/glibc_2.33.bb | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/meta/recipes-core/glibc/glibc_2.33.bb b/meta/recipes-core/glibc/glibc_2.33.bb
> > index 75a1f36d6b..c805755bb9 100644
> > --- a/meta/recipes-core/glibc/glibc_2.33.bb
> > +++ b/meta/recipes-core/glibc/glibc_2.33.bb
> > @@ -95,6 +95,7 @@ EXTRA_OECONF += "${@get_libc_fpu_setting(bb, d)}"
> >
> >  EXTRA_OECONF_append_x86 = " --enable-cet"
> >  EXTRA_OECONF_append_x86-64 = " --enable-cet"
> > +EXTRA_OECONF_append_aarch64 = " --enable-memory-tagging"
> >
> >  PACKAGECONFIG ??= "nscd"
> >  PACKAGECONFIG[nscd] = "--enable-nscd,--disable-nscd"
> > --
> > 2.31.1
> >
> >
> > 
> >