[PATCH] suspend: fix suspend on single-CPU systems

Clark Williams reported that suspend doesnt work on his laptop on
2.6.20-rc1-rt kernels. The bug was introduced by the following cleanup
commit:

 commit 112cecb2cc0e7341db92281ba04b26c41bb8146d
 Author: Siddha, Suresh B <suresh.b.siddha@intel.com>
 Date:   Wed Dec 6 20:34:31 2006 -0800

    [PATCH] suspend: don't change cpus_allowed for task initiating the suspend

because with this change 'error' is not initialized to 0 anymore, if
there are no other online CPUs. (i.e. if the system is single-CPU).

the fix is the initialize it to 0. The really weird thing is that my
version of gcc does not warn about this non-initialized variable
situation ...

(also fix the kernel printk in the error branch, it was missing a
 newline)

Reported-by: Clark Williams <williams@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 9124669f45860cac40c7b03060ef582b94d595ec..241064a32241137103cb3fa834181295e9bec994 100644 (file)
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -258,7 +258,7 @@ static cpumask_t frozen_cpus;
 
 int disable_nonboot_cpus(void)
 {
-       int cpu, first_cpu, error;
+       int cpu, first_cpu, error = 0;
 
        mutex_lock(&cpu_add_remove_lock);
        first_cpu = first_cpu(cpu_present_map);
@@ -294,7 +294,7 @@ int disable_nonboot_cpus(void)
                /* Make sure the CPUs won't be enabled by someone else */
                cpu_hotplug_disabled = 1;
        } else {
-               printk(KERN_ERR "Non-boot CPUs are not disabled");
+               printk(KERN_ERR "Non-boot CPUs are not disabled\n");
        }
 out:
        mutex_unlock(&cpu_add_remove_lock);