Commit 1ae1b5f0 authored Dec 18, 2010 by Russell King

ARM: smp: avoid incrementing mm_users on CPU startup



We should not be incrementing mm_users when we startup a secondary
CPU - doing so results in mm_users incrementing by one each time we
hotplug a CPU, which will eventually wrap, and will cause problems.

Other architectures such as x86 do not increment mm_users, but only
mm_count, so we follow that pattern.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

parent c15524a4

arch/arm/kernel/smp.c

+0 −1

Original line number	Diff line number	Diff line
		@@ -310,7 +310,6 @@ asmlinkage void __cpuinit secondary_start_kernel(void)
		* All kernel threads share the same mm context; grab a
		* reference and switch to it.
		*/
		atomic_inc(&mm->mm_users);
		atomic_inc(&mm->mm_count);
		current->active_mm = mm;
		cpumask_set_cpu(cpu, mm_cpumask(mm));

Admin message