4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Helge Deller <deller@xxxxxx> commit 649aa24254e85bf6bd7807dd372d083707852b1f upstream. This is because of commit f98db6013c55 ("sched/core: Add switch_mm_irqs_off() and use it in the scheduler") in which switch_mm_irqs_off() is called by the scheduler, vs switch_mm() which is used by use_mm(). This patch lets the parisc code mirror the x86 and powerpc code, ie. it disables interrupts in switch_mm(), and optimises the scheduler case by defining switch_mm_irqs_off(). Signed-off-by: Helge Deller <deller@xxxxxx> Signed-off-by: Helge Deller <deller@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/parisc/include/asm/mmu_context.h | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) --- a/arch/parisc/include/asm/mmu_context.h +++ b/arch/parisc/include/asm/mmu_context.h @@ -49,15 +49,26 @@ static inline void load_context(mm_conte mtctl(__space_to_prot(context), 8); } -static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk) +static inline void switch_mm_irqs_off(struct mm_struct *prev, + struct mm_struct *next, struct task_struct *tsk) { - if (prev != next) { mtctl(__pa(next->pgd), 25); load_context(next->context); } } +static inline void switch_mm(struct mm_struct *prev, + struct mm_struct *next, struct task_struct *tsk) +{ + unsigned long flags; + + local_irq_save(flags); + switch_mm_irqs_off(prev, next, tsk); + local_irq_restore(flags); +} +#define switch_mm_irqs_off switch_mm_irqs_off + #define deactivate_mm(tsk,mm) do { } while (0) static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)