Re: [PATCH] ia64: don't do IA64_CMPXCHG_DEBUG without CONFIG_PRINTK

[Randy Dunlap]

On 9/26/21 2:10 AM, John Paul Adrian Glaubitz wrote:
> Hi Randy!
>
> On 9/26/21 08:33, Randy Dunlap wrote:
> > When CONFIG_PRINTK is not set, the CMPXCHG_BUGCHECK() macro calls
> > _printk(), but _printk() is a static inline function, not available
> > as an extern.
> > Since the purpose of the macro is to print the BUGCHECK info,
> > make this config option depend on PRINTK.
> >
> > Fixes multiple occurrences of this build error:
> >
> > ../include/linux/printk.h:208:5: error: static declaration of '_printk' follows non-static declaration
> >    208 | int _printk(const char *s, ...)
> >        |     ^~~~~~~
> > In file included from ../arch/ia64/include/asm/cmpxchg.h:5,
> > ../arch/ia64/include/uapi/asm/cmpxchg.h:146:28: note: previous declaration of '_printk' with type 'int(const char *, ...)'
> >    146 |                 extern int _printk(const char *fmt, ...);
> >
> > Fixes: 337015573718 ("printk: Userspace format indexing support")
> > Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> > Cc: linux-ia64@xxxxxxxxxxxxxxx
> > Cc: Petr Mladek <pmladek@xxxxxxxx>
> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> > Cc: Tony Luck <tony.luck@xxxxxxxxx>
> > Cc: Chris Down <chris@xxxxxxxxxxxxxx>
> > ---
> >   arch/ia64/Kconfig.debug |    2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > --- linux-next-20210917.orig/arch/ia64/Kconfig.debug
> > +++ linux-next-20210917/arch/ia64/Kconfig.debug
> > @@ -39,7 +39,7 @@ config DISABLE_VHPT
> >   
> >   config IA64_DEBUG_CMPXCHG
> >   	bool "Turn on compare-and-exchange bug checking (slow!)"
> > -	depends on DEBUG_KERNEL
> > +	depends on DEBUG_KERNEL && PRINTK
> >   	help
> >   	  Selecting this option turns on bug checking for the IA-64
> >   	  compare-and-exchange instructions.  This is slow!  Itaniums
>
> We currently don't have a maintainer for ia64 - although I would be willing to pick
> up the job - so your patch would have to go through someone else's tree.

Yes, I know about no-maintainer. That's why Andrew is cc-ed on this.
(or even Peter could merge it.)

> I can boot test the patch on my RX2660 in the mean time.


and Chris wrote:

> This Fixes tag doesn't make much sense. This was already broken long before that patch, just the error message changed: printk() was already static inline on !CONFIG_PRINTK for eons. 

OK, I corrected that for v2. Thanks.

--
~Randy