4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Andy Lutomirski luto@kernel.org
commit f98db6013c557c216da5038d9c52045be55cd039 upstream.
By default, this is the same thing as switch_mm().
x86 will override it as an optimization.
Signed-off-by: Andy Lutomirski luto@kernel.org Reviewed-by: Borislav Petkov bp@suse.de Cc: Borislav Petkov bp@alien8.de Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Link: http://lkml.kernel.org/r/df401df47bdd6be3e389c6f1e3f5310d70e81b2c.1461688545... Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- include/linux/mmu_context.h | 7 +++++++ kernel/sched/core.c | 6 +++--- 2 files changed, 10 insertions(+), 3 deletions(-)
--- a/include/linux/mmu_context.h +++ b/include/linux/mmu_context.h @@ -1,9 +1,16 @@ #ifndef _LINUX_MMU_CONTEXT_H #define _LINUX_MMU_CONTEXT_H
+#include <asm/mmu_context.h> + struct mm_struct;
void use_mm(struct mm_struct *mm); void unuse_mm(struct mm_struct *mm);
+/* Architectures that care about IRQ state in switch_mm can override this. */ +#ifndef switch_mm_irqs_off +# define switch_mm_irqs_off switch_mm +#endif + #endif --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -32,7 +32,7 @@ #include <linux/init.h> #include <linux/uaccess.h> #include <linux/highmem.h> -#include <asm/mmu_context.h> +#include <linux/mmu_context.h> #include <linux/interrupt.h> #include <linux/capability.h> #include <linux/completion.h> @@ -2708,7 +2708,7 @@ context_switch(struct rq *rq, struct tas atomic_inc(&oldmm->mm_count); enter_lazy_tlb(oldmm, next); } else - switch_mm(oldmm, mm, next); + switch_mm_irqs_off(oldmm, mm, next);
if (!prev->mm) { prev->active_mm = NULL; @@ -5206,7 +5206,7 @@ void idle_task_exit(void) BUG_ON(cpu_online(smp_processor_id()));
if (mm != &init_mm) { - switch_mm(mm, &init_mm, current); + switch_mm_irqs_off(mm, &init_mm, current); finish_arch_post_lock_switch(); } mmdrop(mm);