Re: [PATCH rtw-next] wifi: rtw88: 8814a: add __packed to ensure efuse map size

[Ping-Ke Shih <pkshih@realtek.com>]

Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:

> On 10/04/2026 16:13, Ping-Ke Shih wrote:
> > All nested sture/union used by efuse map should be packed. Otherwise, a
> > arm-linux-gnueabi-gcc compiler might throw errors due to size assertion.
> >
> >    In file included from include/linux/bitfield.h:10,
> >                     from include/linux/fortify-string.h:5,
> >                     from include/linux/string.h:389,
> >                     from include/linux/uuid.h:11,
> >                     from include/linux/mod_devicetable.h:14,
> >                     from include/linux/usb.h:5,
> >                     from drivers/net/wireless/realtek/rtw88/rtw8814a.c:5:
> >>> include/linux/build_bug.h:78:41: error: static assertion failed: "sizeof(struct rtw8814a_efuse) == 512"
> >     #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
> >                                             ^~~~~~~~~~~~~~
> >
> > Fixes: 1a7545784642 ("wifi: rtw88: Add rtw8814a.{c,h}")
> > Reported-by: kernel test robot <lkp@intel.com>
> > Closes:  https://lore.kernel.org/oe-kbuild-all/202604101721.fsv5XmCX-lkp@intel.com/
> > Cc: Bitterblue Smith <rtl8821cerfe2@gmail.com>
> > Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
> > ---
> >  drivers/net/wireless/realtek/rtw88/main.h     | 2 +-
> >  drivers/net/wireless/realtek/rtw88/rtw8814a.h | 2 +-
> >  2 files changed, 2 insertions(+), 2 deletions(-)
> >
> 
> Thank you for taking care of this. Actually, every chip's efuse struct
> has a union like this missing __packed, not just RTL8814A. Most of them
> don't have a static_assert.
> 

Indeed. I added size assetion of efuse map entirely to rtw88 and rtw89 [1],
hoping we can find and address this kind of problem earlier.

[1] https://lore.kernel.org/linux-wireless/20260411072413.1556575-1-pkshih@realtek.com/T/#t