[6.18.y] Request: 10a47fb67340 ("tools: linux/types.h: Add 128-bit integer types for arm64 UAPI structures")

[6.18.y] Request: 10a47fb67340 ("tools: linux/types.h: Add 128-bit integer types for arm64 UAPI structures")

[Marco Schirrmeister]

Hi,

please backport upstream commit

  10a47fb67340 ("tools: linux/types.h: Add 128-bit integer types for arm64 UAPI structures")

to 6.18.y and the other supported LTS branches where it applies.

Will Deacon agreed it should go to stable and Jeremy Linton requested it
in September, but it doesn't seem to have been picked up:
https://lore.kernel.org/all/aplSEuD_h9OPOZoD@willie-the-truck/
https://lore.kernel.org/stable/bbbc33a1-cfd6-4cac-82c0-253888ca933a@arm.com/

Distros now ship 7.3 uapi headers (e.g. Arch Linux ARM's
linux-api-headers 7.3), and native arm64 builds of 6.18.63 fail in
tools/bpf/resolve_btfids (libsubcmd, libbpf):

  /usr/include/asm/sigcontext.h:81:9: error: unknown type name '__u128'

The commit applies cleanly to 6.18.63 and fixes the build. Only this
patch is needed, not the follow-up arm64 uapi change (d4bf9e08d412).

Thanks,
Marco

Re: [6.18.y] Request: 10a47fb67340 ("tools: linux/types.h: Add 128-bit integer types for arm64 UAPI structures")

[Sasha Levin]

On 2026-11-12, Marco Schirrmeister wrote:
> [6.18.y] Request: 10a47fb67340 ("tools: linux/types.h: Add 128-bit integer types for arm64 UAPI structures")
> Hi,
> please backport upstream commit
>   10a47fb67340 ("tools: linux/types.h: Add 128-bit integer types for arm64 UAPI structures")

10a47fb67340 ("tools: linux/types.h: Add 128-bit integer types for arm64 UAPI
structures") only adds typedefs for d4bf9e08d412 ("arm64: uapi: Use __u128
instead of __uint128_t in UAPI headers"), which no stable tree has, and nothing
in them uses the new types.

What breaks on 6.18.y without it? If it is the resolve_btfids build against
distro uapi headers, please say so and we can look again.


-- 
Thanks,
Sasha

Re: [6.18.y] Request: 10a47fb67340 ("tools: linux/types.h: Add 128-bit integer types for arm64 UAPI structures")

[Marco Schirrmeister]

On Thu, Nov 12, 2026 at 09:33:22PM +0100, Sasha Levin wrote:
> What breaks on 6.18.y without it? If it is the resolve_btfids build against
> distro uapi headers, please say so and we can look again.

Yes, that is exactly it.

I build 6.18.y natively (with CONFIG_DEBUG_INFO_BTF=y) on arm64
(Arch Linux ARM). Since the distro updated its kernel headers
to 7.3, the build fails in resolve_btfids with this error:

  /usr/include/asm/sigcontext.h:81:9: error: unknown type name '__u128'

The kernel tree itself does not use __u128, but the newer system headers
do, and the old tools/include/linux/types.h does not define it. With
10a47fb67340 applied, 6.18.63 builds again without issues.

Debian 13 ships 7.3 headers too, so other arm64 users will probably run
into the same thing.

Thanks,
Marco

Re: [6.18.y] Request: 10a47fb67340 ("tools: linux/types.h: Add 128-bit integer types for arm64 UAPI structures")

[Sasha Levin]

On 2026-11-13, Marco Schirrmeister <mschirrmeister@gmail.com> wrote:
> With
> 10a47fb67340 applied, 6.18.63 builds again without issues.

Thanks, that answers it. Queued for 6.18, 6.12, 6.6, 6.1, 5.15 and 5.10.

-- 
Thanks,
Sasha