Re: [tty:tty-next 27/37] drivers/tty/vt/keyboard.c:1712:7: error: cannot jump from this asm goto statement to one of its possible targets

[Nathan Chancellor <nathan@kernel.org>]

On Mon, Nov 24, 2025 at 06:25:26PM +0800, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-next
> head:   da218406dd50e0ac96bb383de4edd208286efe70
> commit: bfb24564b5fd8625ce5c007f274cabdc3b570969 [27/37] tty: vt/keyboard: use __free()
> config: powerpc-randconfig-002-20251124 (https://download.01.org/0day-ci/archive/20251124/202511241835.EA8lShgH-lkp@intel.com/config)
> compiler: clang version 16.0.6 (https://github.com/llvm/llvm-project 7cbf1a2591520c2491aa35339f227775f4d3adf6)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251124/202511241835.EA8lShgH-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202511241835.EA8lShgH-lkp@intel.com/
> 
> All errors (new ones prefixed by >>):
> 
> >> drivers/tty/vt/keyboard.c:1712:7: error: cannot jump from this asm goto statement to one of its possible targets
>                    if (put_user(asize, &a->kb_cnt))
>                        ^
>    arch/powerpc/include/asm/uaccess.h:67:5: note: expanded from macro 'put_user'
>                      __put_user(x, _pu_addr) : -EFAULT;                    \
>                      ^
>    arch/powerpc/include/asm/uaccess.h:49:3: note: expanded from macro '__put_user'
>                    __put_user_size_goto(__pu_val, __pu_addr, __pu_size, __pu_failed);      \
>                    ^
>    arch/powerpc/include/asm/uaccess.h:127:10: note: expanded from macro '__put_user_size_goto'
>            case 1: __put_user_asm_goto(x, __pus_addr, label, "stb"); break;        \
>                    ^
>    arch/powerpc/include/asm/uaccess.h:87:2: note: expanded from macro '__put_user_asm_goto'
>            asm goto(                                       \
>            ^
>    drivers/tty/vt/keyboard.c:1736:7: note: possible target of asm goto statement
>                    if (put_user(asize, &a->kb_cnt))
>                        ^
>    arch/powerpc/include/asm/uaccess.h:67:5: note: expanded from macro 'put_user'
>                      __put_user(x, _pu_addr) : -EFAULT;                    \
>                      ^
>    arch/powerpc/include/asm/uaccess.h:53:9: note: expanded from macro '__put_user'
>                                                                    \
>                                                                    ^
>    drivers/tty/vt/keyboard.c:1692:33: note: jump exits scope of variable with __attribute__((cleanup))
>                    struct kbdiacr __free(kfree) *dia = kmalloc_array(MAX_DIACR, sizeof(struct kbdiacr),
>                                                  ^
>    drivers/tty/vt/keyboard.c:1722:23: note: jump bypasses initialization of variable with __attribute__((cleanup))
>                    void __free(kfree) *buf = kmalloc_array(MAX_DIACR, sizeof(struct kbdiacruc),
>                                        ^

Previously reported:

  https://lore.kernel.org/202509091702.Oc7eCRDw-lkp@intel.com/

My suggested workaround in that thread is still applicable if it would
be acceptable as a formal patch:

  https://lore.kernel.org/20250909215342.GA2456480@ax162/

Cheers,
Nathan