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Diffstat (limited to 'arch/arm64/include/asm/mmu_context.h')
-rw-r--r--arch/arm64/include/asm/mmu_context.h46
1 files changed, 23 insertions, 23 deletions
diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h
index 3257895a9b5e..9d155fa9a507 100644
--- a/arch/arm64/include/asm/mmu_context.h
+++ b/arch/arm64/include/asm/mmu_context.h
@@ -156,29 +156,21 @@ void check_and_switch_context(struct mm_struct *mm, unsigned int cpu);
#define init_new_context(tsk,mm) ({ atomic64_set(&(mm)->context.id, 0); 0; })
-/*
- * This is called when "tsk" is about to enter lazy TLB mode.
- *
- * mm: describes the currently active mm context
- * tsk: task which is entering lazy tlb
- * cpu: cpu number which is entering lazy tlb
- *
- * tsk->mm will be NULL
- */
-static inline void
-enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
-{
-}
-
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
static inline void update_saved_ttbr0(struct task_struct *tsk,
struct mm_struct *mm)
{
- if (system_uses_ttbr0_pan()) {
- BUG_ON(mm->pgd == swapper_pg_dir);
- task_thread_info(tsk)->ttbr0 =
- virt_to_phys(mm->pgd) | ASID(mm) << 48;
- }
+ u64 ttbr;
+
+ if (!system_uses_ttbr0_pan())
+ return;
+
+ if (mm == &init_mm)
+ ttbr = __pa_symbol(empty_zero_page);
+ else
+ ttbr = virt_to_phys(mm->pgd) | ASID(mm) << 48;
+
+ task_thread_info(tsk)->ttbr0 = ttbr;
}
#else
static inline void update_saved_ttbr0(struct task_struct *tsk,
@@ -187,6 +179,16 @@ static inline void update_saved_ttbr0(struct task_struct *tsk,
}
#endif
+static inline void
+enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
+{
+ /*
+ * We don't actually care about the ttbr0 mapping, so point it at the
+ * zero page.
+ */
+ update_saved_ttbr0(tsk, &init_mm);
+}
+
static inline void __switch_mm(struct mm_struct *next)
{
unsigned int cpu = smp_processor_id();
@@ -214,11 +216,9 @@ switch_mm(struct mm_struct *prev, struct mm_struct *next,
* Update the saved TTBR0_EL1 of the scheduled-in task as the previous
* value may have not been initialised yet (activate_mm caller) or the
* ASID has changed since the last run (following the context switch
- * of another thread of the same process). Avoid setting the reserved
- * TTBR0_EL1 to swapper_pg_dir (init_mm; e.g. via idle_task_exit).
+ * of another thread of the same process).
*/
- if (next != &init_mm)
- update_saved_ttbr0(tsk, next);
+ update_saved_ttbr0(tsk, next);
}
#define deactivate_mm(tsk,mm) do { } while (0)