Commit 1a2142af authored by Rusty Russell's avatar Rusty Russell
Browse files

cpumask: remove dangerous CPU_MASK_ALL_PTR, &CPU_MASK_ALL 



Impact: cleanup

(Thanks to Al Viro for reminding me of this, via Ingo)

CPU_MASK_ALL is the (deprecated) "all bits set" cpumask, defined as so:

	#define CPU_MASK_ALL (cpumask_t) { { ... } }

Taking the address of such a temporary is questionable at best,
unfortunately 321a8e9d (cpumask: add CPU_MASK_ALL_PTR macro) added
CPU_MASK_ALL_PTR:

	#define CPU_MASK_ALL_PTR (&CPU_MASK_ALL)

Which formalizes this practice.  One day gcc could bite us over this
usage (though we seem to have gotten away with it so far).

So replace everywhere which used &CPU_MASK_ALL or CPU_MASK_ALL_PTR
with the modern "cpu_all_mask" (a real const struct cpumask *).

Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
Acked-by: default avatarIngo Molnar <mingo@elte.hu>
Reported-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Cc: Mike Travis <travis@sgi.com>
parent 0d34fb8e

init/main.c

+1 −1
Original line number Diff line number Diff line
@@ -842,7 +842,7 @@ static int __init kernel_init(void * unused) 
	/*

	 * init can run on any cpu.

	 */

	set_cpus_allowed_ptr(current, CPU_MASK_ALL_PTR);

	set_cpus_allowed_ptr(current, cpu_all_mask);

	/*

	 * Tell the world that we're going to be the grim

	 * reaper of innocent orphaned children.

kernel/kmod.c

+1 −1
Original line number Diff line number Diff line
@@ -167,7 +167,7 @@ static int ____call_usermodehelper(void *data) 
	}



	/* We can run anywhere, unlike our parent keventd(). */

	set_cpus_allowed_ptr(current, CPU_MASK_ALL_PTR);

	set_cpus_allowed_ptr(current, cpu_all_mask);



	/*

	 * Our parent is keventd, which runs with elevated scheduling priority.

kernel/kthread.c

+2 −2
Original line number Diff line number Diff line
@@ -110,7 +110,7 @@ static void create_kthread(struct kthread_create_info *create) 
		 */

		sched_setscheduler(create->result, SCHED_NORMAL, &param);

		set_user_nice(create->result, KTHREAD_NICE_LEVEL);

		set_cpus_allowed_ptr(create->result, CPU_MASK_ALL_PTR);

		set_cpus_allowed_ptr(create->result, cpu_all_mask);

	}

	complete(&create->done);

}
@@ -240,7 +240,7 @@ int kthreadd(void *unused) 
	set_task_comm(tsk, "kthreadd");

	ignore_signals(tsk);

	set_user_nice(tsk, KTHREAD_NICE_LEVEL);

	set_cpus_allowed_ptr(tsk, CPU_MASK_ALL_PTR);

	set_cpus_allowed_ptr(tsk, cpu_all_mask);



	current->flags |= PF_NOFREEZE | PF_FREEZER_NOSIG;

mm/pdflush.c

+1 −1
Original line number Diff line number Diff line
@@ -191,7 +191,7 @@ static int pdflush(void *dummy) 


	/*

	 * Some configs put our parent kthread in a limited cpuset,

	 * which kthread() overrides, forcing cpus_allowed == CPU_MASK_ALL.

	 * which kthread() overrides, forcing cpus_allowed == cpu_all_mask.

	 * Our needs are more modest - cut back to our cpusets cpus_allowed.

	 * This is needed as pdflush's are dynamically created and destroyed.

	 * The boottime pdflush's are easily placed w/o these 2 lines.

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