Re: 2.6.37-rc1 build failure

[Randy Dunlap <randy.dunlap@oracle.com>]

On 11/10/10 04:59, Peter Zijlstra wrote:
> On Wed, 2010-11-03 at 21:34 -0700, Randy Dunlap wrote:
>> The build fails for me with the given .config file.
>> It's due to selects and depends, finally comes down to HAVE_PERF_EVENTS not being
>> enabled for M386 or M486.  Do you actually have a processor of that vintage?
> 
> FWIW this .config generates a _TON_ of Kconfig dep warnings..

Yeah, they are all MEDIA-related, known about, and someone is working
on the problem.

> Urgh, Kconfig hell.
> 
> config PERF_EVENTS
>         bool "Kernel performance events and counters"
>         default y if (PROFILING || PERF_COUNTERS)
>         depends on HAVE_PERF_EVENTS
>         select ANON_INODES
>         select IRQ_WORK
> 
> 
> # grep PERF_EVENTS borken-build/.config
> CONFIG_PERF_EVENTS=y
> CONFIG_HAVE_PERF_EVENTS_NMI=y
> 
> 
> 
> So we managed to get PERF_EVENTS=y even though its dependency
> HAVE_PERF_EVENTS=n.
> 
> 
> I bet that's because of:
> 
> config X86
>         select HAVE_PERF_EVENTS if (!M386 && !M486)
>         select PERF_EVENTS 

Yep.

> 
> Ingo, should we simply do something like the below patch?
> 
> ---
> Subject: x86: Remove M[34]86 conditional on HAVE_PERF_EVENTS
> 
> x86 requires PERF_EVENTS because of the hardware breakpoint mess,
> so don't make it conditional on M[34]86.
> 
> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>

Acked-by: Randy Dunlap <randy.dunlap@oracle.com>

Thanks.

> ---
>  arch/x86/Kconfig |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index e832768..e330da2 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -21,7 +21,7 @@ config X86
>  	select HAVE_UNSTABLE_SCHED_CLOCK
>  	select HAVE_IDE
>  	select HAVE_OPROFILE
> -	select HAVE_PERF_EVENTS if (!M386 && !M486)
> +	select HAVE_PERF_EVENTS
>  	select HAVE_IRQ_WORK
>  	select HAVE_IOREMAP_PROT
>  	select HAVE_KPROBES
> 


-- 
~Randy
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