Re: [bug] latest -git boot hang

[Jens Axboe <jens.axboe@oracle.com>]

On Sat, Oct 11 2008, Ingo Molnar wrote:
> 
> * Tejun Heo <tj@kernel.org> wrote:
> 
> > > It does sound like perhaps the option should be hidden more, if it's 
> > > really only reasonably enabled for some very specialized distro 
> > > debuggers, not normal kernel people.
> > 
> > Yeap, if fedora didn't work, I think it should be hidden.  Do we 
> > already have place to hide things like this?
> 
> in my local testing i'm using simple annotations like the one attached 
> further below. Any objections against sending my BROKEN_BOOT_ALLOWED kit 
> upstream, and merge my annotations for various kernel features that 
> break a generic distro bootup?
> 
> Right now i have about 40 such annotations for -tip testing:
> 
>   fs/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   fs/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   security/selinux/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   security/smack/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   security/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/net/appletalk/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/net/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/media/video/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/scsi/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/watchdog/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/watchdog/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/ide/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/i2c/busses/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/block/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/video/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/video/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/video/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/video/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/video/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/video/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/video/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/video/console/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/video/console/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/mtd/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   drivers/isdn/icn/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   lib/Kconfig.kgdb:	depends on BROKEN_BOOT_ALLOWED
>   lib/Kconfig.debug:	depends on BROKEN_BOOT_ALLOWED
>   lib/Kconfig.debug:	depends on BROKEN_BOOT_ALLOWED
>   arch/x86/Kconfig.debug:	depends on BROKEN_BOOT_ALLOWED
>   arch/x86/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   arch/x86/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   arch/x86/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   arch/x86/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   arch/x86/Kconfig:	# depends on BROKEN_BOOT_ALLOWED
>   arch/x86/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   arch/x86/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   arch/x86/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   arch/x86/Kconfig:	depends on BROKEN_BOOT_ALLOWED
>   arch/x86/Kconfig.cpu:	depends on BROKEN_BOOT_ALLOWED
> 
> and note the stark contrast to CONFIG_BROKEN - sometimes a given 
> functionality is really not meant to be enabled on a generic system.
> 
> 	Ingo
> 
> ---------------->
> Subject: qa: no ext devt
> From: Ingo Molnar <mingo@elte.hu>
> Date: Fri Oct 10 22:54:57 CEST 2008
> 
> Signed-off-by: Ingo Molnar <mingo@elte.hu>
> ---
>  lib/Kconfig.debug |    2 ++
>  1 file changed, 2 insertions(+)
> 
> Index: linux/lib/Kconfig.debug
> ===================================================================
> --- linux.orig/lib/Kconfig.debug
> +++ linux/lib/Kconfig.debug
> @@ -670,6 +670,8 @@ config DEBUG_BLOCK_EXT_DEVT
>          bool "Force extended block device numbers and spread them"
>  	depends on DEBUG_KERNEL
>  	depends on BLOCK
> +	depends on BROKEN_BOOT_ALLOWED
> +	select BROKEN_BOOT
>  	default n
>  	help
>  	  Conventionally, block device numbers are allocated from

What is BROKEN_BOOT_ALLOWED? Honestly, I'd prefer to just put an extra
2-3 line paragraph in the help entry, saying that it's quite possible
that current distros wont boot with this testing code enabled. Since it
default to 'n', people should read the entry before turning it on
anyway.

-- 
Jens Axboe