Re: 3.9-rc1 powerpc ptrace.c: 'brk.len' is used uninitialized

From: Philippe De Muyter
Date: Thu Mar 07 2013 - 04:59:18 EST


Hello Mikey,

On Thu, Mar 07, 2013 at 10:14:30AM +1100, Michael Neuling wrote:
> Philippe De Muyter <phdm@xxxxxxxxx> wrote:
>
> > On Thu, Mar 07, 2013 at 09:09:48AM +1100, Michael Neuling wrote:
> > > > bisect tells me that since your commit 9422de3e953d0e60eb95f5430a9dd803eec1c6d7
> > > > "powerpc: Hardware breakpoints rewrite to handle non DABR breakpoint registers",
> > > > compiling linux fails with :
> > > >
> > > > cc1: warnings being treated as errors
> > > > arch/powerpc/kernel/ptrace.c: In function 'arch_ptrace':
> > > > arch/powerpc/kernel/ptrace.c:1450: warning: 'brk.len' is used uninitialized in this function
> > > > arch/powerpc/kernel/ptrace.c:1352: note: 'brk.len' was declared here
> > > >
> > > > could you look at that ?
> > >
> > > Sure.
> >
> > I use gcc-4.2.2, and my .config follows.
>
> I'm a bit lost.
>
> I don't have 4.2.2 (which is ancient BTW) and I can't hit this on
> 4.3,4.5 or 4.6 with your config. It compiles fine.
>
> Also:
>
> > arch/powerpc/kernel/ptrace.c:1450: warning: 'brk.len' is used uninitialized in this function
> > arch/powerpc/kernel/ptrace.c:1352: note: 'brk.len' was declared here
>
> These line numbers make no sense at all WRT v3.9-rc1. brk.len is neither
> declared or used in those lines:

those were the line numbers just after your commit

In 3.9-rc1 they are :

cc1: warnings being treated as errors
arch/powerpc/kernel/ptrace.c: In function 'arch_ptrace':
arch/powerpc/kernel/ptrace.c:1479: warning: 'brk.len' is used uninitialized in this function
arch/powerpc/kernel/ptrace.c:1381: note: 'brk.len' was declared here

if (child->thread.hw_brk.address)
return -ENOSPC;

1479: child->thread.hw_brk = brk;

return 1;
#endif /* !CONFIG_PPC_ADV_DEBUG_DVCS */

Philippe
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/