Re: [stable] Patch Upstream: hw_breakpoints, powerpc: Fix CONFIG_HAVE_HW_BREAKPOINT off-case in ptrace_set_debugreg()

On Sat, May 07, 2011 at 09:20:02PM +0000, James Bottomley wrote:

commit: 925f83c085e1bb08435556c5b4844a60de002e31
From: Frederic Weisbecker <redacted>
Date: Fri, 6 May 2011 01:53:18 +0200
Subject: [PATCH] hw_breakpoints, powerpc: Fix CONFIG_HAVE_HW_BREAKPOINT
 off-case in ptrace_set_debugreg()

We make use of ptrace_get_breakpoints() / ptrace_put_breakpoints() to
protect ptrace_set_debugreg() even if CONFIG_HAVE_HW_BREAKPOINT if off.
However in this case, these APIs are not implemented.

To fix this, push the protection down inside the relevant ifdef.
Best would be to export the code inside
CONFIG_HAVE_HW_BREAKPOINT into a standalone function to cleanup
the ifdefury there and call the breakpoint ref API inside. But
as it is more invasive, this should be rather made in an -rc1.

Fixes this build error:

  arch/powerpc/kernel/ptrace.c:1594: error: implicit declaration of function 'ptrace_get_breakpoints' make[2]: ***

Reported-by: Ingo Molnar <redacted>
Signed-off-by: Frederic Weisbecker <redacted>
Cc: LPPC <redacted>
Cc: Prasad <redacted>
Cc: v2.6.33.. <stable@kernel.org>

This patch applied after I tweaked it to the .38-stable tree, but it
doesn't apply at all to 2.6.33-stable.  If someone wants to see it
there, please send a backported patch to stable@kernel.org.