The unpacked unions within a packed struct generates alignment warnings
on clang for 32-bit ARM.

With the recent changes to compile-test the UAPI headers in more cases,
these warning in combination with CONFIG_WERROR breaks the build.

Fix the warnings.

Intended for the kbuild tree.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
Thomas Weißschuh (2):
      hyper-v: Mark inner union in hv_kvp_exchg_msg_value as packed
      virt: vbox: uapi: Mark inner unions in packed structs as packed

 include/uapi/linux/hyperv.h            | 2 +-
 include/uapi/linux/vbox_vmmdev_types.h | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)
---
base-commit: e3970d77ec504e54c3f91a48b2125775c16ba4c0
change-id: 20260115-kbuild-alignment-vbox-d0409134d335

Best regards,
-- 
Thomas Weißschuh <thomas.weissschuh@linutronix.de>

On Thu, 15 Jan 2026 08:35:43 +0100, Thomas Weißschuh wrote:
> The unpacked unions within a packed struct generates alignment warnings
> on clang for 32-bit ARM.
> 
> With the recent changes to compile-test the UAPI headers in more cases,
> these warning in combination with CONFIG_WERROR breaks the build.
> 
> Fix the warnings.
> 
> [...]

Applied to

  https://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux.git kbuild-next

Thanks!

[1/2] hyper-v: Mark inner union in hv_kvp_exchg_msg_value as packed
      https://git.kernel.org/kbuild/c/1e5271393d777
[2/2] virt: vbox: uapi: Mark inner unions in packed structs as packed
      https://git.kernel.org/kbuild/c/c25d01e1c4f2d

Please look out for regression or issue reports or other follow up
comments, as they may result in the patch/series getting dropped or
reverted. Patches applied to an "unstable" branch are accepted pending
wider testing in -next and any post-commit review; they will generally
be moved to the main branch in a week if no issues are found.

Best regards,
-- 
Nathan Chancellor <nathan@kernel.org>

Cc += linux-kbuild

On Thu, Jan 15, 2026 at 08:35:43AM +0100, Thomas Weißschuh wrote:
> The unpacked unions within a packed struct generates alignment warnings
> on clang for 32-bit ARM.
> 
> With the recent changes to compile-test the UAPI headers in more cases,
> these warning in combination with CONFIG_WERROR breaks the build.
> 
> Fix the warnings.
> 
> Intended for the kbuild tree.
> 
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> ---
> Thomas Weißschuh (2):
>       hyper-v: Mark inner union in hv_kvp_exchg_msg_value as packed
>       virt: vbox: uapi: Mark inner unions in packed structs as packed
> 
>  include/uapi/linux/hyperv.h            | 2 +-
>  include/uapi/linux/vbox_vmmdev_types.h | 4 ++--
>  2 files changed, 3 insertions(+), 3 deletions(-)
> ---
> base-commit: e3970d77ec504e54c3f91a48b2125775c16ba4c0
> change-id: 20260115-kbuild-alignment-vbox-d0409134d335
> 
> Best regards,
> -- 
> Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> 

Thanks!

Tested-by: Nicolas Schier <nsc@kernel.org>
Reviewed-by: Nicolas Schier <nsc@kernel.org>

Kind regards,
Nicolas

On Thu, Jan 15, 2026 at 08:35:43AM +0100, Thomas Weißschuh wrote:
> The unpacked unions within a packed struct generates alignment warnings
> on clang for 32-bit ARM.
> 
> With the recent changes to compile-test the UAPI headers in more cases,
> these warning in combination with CONFIG_WERROR breaks the build.
> 
> Fix the warnings.
> 
> Intended for the kbuild tree.
> 
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> ---
> Thomas Weißschuh (2):
>       hyper-v: Mark inner union in hv_kvp_exchg_msg_value as packed
>       virt: vbox: uapi: Mark inner unions in packed structs as packed
> 
>  include/uapi/linux/hyperv.h            | 2 +-
>  include/uapi/linux/vbox_vmmdev_types.h | 4 ++--
>  2 files changed, 3 insertions(+), 3 deletions(-)
> ---
> base-commit: e3970d77ec504e54c3f91a48b2125775c16ba4c0
> change-id: 20260115-kbuild-alignment-vbox-d0409134d335
> 
> Best regards,
> -- 
> Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> 

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>