Re: mmotm 2009-01-28-02-17 uploaded (i386 build errors: cpusets & kexec)

[Andrew Morton <akpm@linux-foundation.org>]

On Thu, 29 Jan 2009 07:09:35 -0500 Neil Horman <nhorman@tuxdriver.com> wrote:

> > > So does that.
> > > 
> > > --- a/kernel/printk.c~kexec-add-dmesg-log-symbols-to-proc-vmcoreinfo-lists-fix-fix
> > > +++ a/kernel/printk.c
> > > @@ -137,11 +137,13 @@ static char *log_buf = __log_buf;
> > >  static int log_buf_len = __LOG_BUF_LEN;
> > >  static unsigned logged_chars; /* Number of chars produced since last read+clear operation */
> > >  
> > > +#ifdef CONFIG_KEXEC
> > >  void log_buf_kexec_setup(void)
> > >  {
> > >  	VMCOREINFO_SYMBOL(log_buf);
> > >  	VMCOREINFO_SYMBOL(log_end);
> > >  }
> > > +#endif
> > >  
> > >  static int __init log_buf_len_setup(char *str)
> > >  {
> > > _
> > 
> > Weird, I thought I checked that just now. In any case this email
> > was already in my inbox. In any case, I can now produce the problem,
> > and this patch resolves it.
> > 
> 
> Sorry, i didn't think to check on conditions when CONFIG_KEXEC wasn't set.  I
> assumed we had a stub for all the VMCOREINFO defines.  Why don't we fix it in
> that manner?  I mean we have serveral arch specific additions to vmcoreinfo, all
> of which apparently must be ifdefd for this to work.  Why not just fix it in
> conditional definition?

I didn't do that because then we'd have an empty function log_buf_kexec_setup()
floating about in every vmlinux.

Hardly a big issue, but a bit regrettable.