Re: [PATCH 4.19 29/32] jump_label: move asm goto support test to Kconfig

[Greg Kroah-Hartman]

On Tue, Jun 04, 2019 at 11:30:32AM +0200, Pavel Machek wrote:
> On Mon 2019-06-03 11:08:23, Greg Kroah-Hartman wrote:
> > From: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> > 
> > commit e9666d10a5677a494260d60d1fa0b73cc7646eb3 upstream.
> > 
> > Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label".
> > 
> > The jump label is controlled by HAVE_JUMP_LABEL, which is defined
> > like this:
> > 
> >   #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
> >   # define HAVE_JUMP_LABEL
> >   #endif
> > 
> > We can improve this by testing 'asm goto' support in Kconfig, then
> > make JUMP_LABEL depend on CC_HAS_ASM_GOTO.
> > 
> > Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will
> > match to the real kernel capability.
> > 
> > Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> > Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> (powerpc)
> > Tested-by: Sedat Dilek <sedat.dilek@xxxxxxxxx>
> > [nc: Fix trivial conflicts in 4.19
> >      arch/xtensa/kernel/jump_label.c doesn't exist yet
> >      Ensured CC_HAVE_ASM_GOTO and HAVE_JUMP_LABEL were sufficiently
> >      eliminated]
> > Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> 
> This does not matche stable-kernel rules. It is nice cleanup, but it
> does not really fix any bug (does it?), and resulting patch is too
> big.

Please see the original email on the stable mailing list for why this
patch was submitted and accepted.

thanks,

greg k-h