Re: [PATCH 4.19 29/32] jump_label: move asm goto support test to Kconfig
From: Greg Kroah-Hartman
Date: Tue Jun 04 2019 - 05:59:24 EST
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
Please see the original email on the stable mailing list for why this
patch was submitted and accepted.