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Diffstat (limited to 'arch/arm/mm/context.c')
-rw-r--r--arch/arm/mm/context.c17
1 files changed, 8 insertions, 9 deletions
diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c
index 8bfae964b13..b0ee9ba3cfa 100644
--- a/arch/arm/mm/context.c
+++ b/arch/arm/mm/context.c
@@ -24,7 +24,9 @@ DEFINE_PER_CPU(struct mm_struct *, current_mm);
/*
* We fork()ed a process, and we need a new context for the child
- * to run in.
+ * to run in. We reserve version 0 for initial tasks so we will
+ * always allocate an ASID. The ASID 0 is reserved for the TTBR
+ * register changing sequence.
*/
void __init_new_context(struct task_struct *tsk, struct mm_struct *mm)
{
@@ -34,11 +36,8 @@ void __init_new_context(struct task_struct *tsk, struct mm_struct *mm)
static void flush_context(void)
{
- u32 ttb;
- /* Copy TTBR1 into TTBR0 */
- asm volatile("mrc p15, 0, %0, c2, c0, 1\n"
- "mcr p15, 0, %0, c2, c0, 0"
- : "=r" (ttb));
+ /* set the reserved ASID before flushing the TLB */
+ asm("mcr p15, 0, %0, c13, c0, 1\n" : : "r" (0));
isb();
local_flush_tlb_all();
if (icache_is_vivt_asid_tagged()) {
@@ -94,7 +93,7 @@ static void reset_context(void *info)
return;
smp_rmb();
- asid = cpu_last_asid + cpu;
+ asid = cpu_last_asid + cpu + 1;
flush_context();
set_mm_context(mm, asid);
@@ -144,13 +143,13 @@ void __new_context(struct mm_struct *mm)
* to start a new version and flush the TLB.
*/
if (unlikely((asid & ~ASID_MASK) == 0)) {
- asid = cpu_last_asid + smp_processor_id();
+ asid = cpu_last_asid + smp_processor_id() + 1;
flush_context();
#ifdef CONFIG_SMP
smp_wmb();
smp_call_function(reset_context, NULL, 1);
#endif
- cpu_last_asid += NR_CPUS - 1;
+ cpu_last_asid += NR_CPUS;
}
set_mm_context(mm, asid);