diff options
Diffstat (limited to 'arch/i386/xen/mmu.c')
| -rw-r--r-- | arch/i386/xen/mmu.c | 29 |
1 files changed, 26 insertions, 3 deletions
diff --git a/arch/i386/xen/mmu.c b/arch/i386/xen/mmu.c index 874db0cd1d2a..c476dfa3ad7a 100644 --- a/arch/i386/xen/mmu.c +++ b/arch/i386/xen/mmu.c @@ -515,20 +515,43 @@ static void drop_other_mm_ref(void *info) if (__get_cpu_var(cpu_tlbstate).active_mm == mm) leave_mm(smp_processor_id()); + + /* If this cpu still has a stale cr3 reference, then make sure + it has been flushed. */ + if (x86_read_percpu(xen_current_cr3) == __pa(mm->pgd)) { + load_cr3(swapper_pg_dir); + arch_flush_lazy_cpu_mode(); + } } static void drop_mm_ref(struct mm_struct *mm) { + cpumask_t mask; + unsigned cpu; + if (current->active_mm == mm) { if (current->mm == mm) load_cr3(swapper_pg_dir); else leave_mm(smp_processor_id()); + arch_flush_lazy_cpu_mode(); + } + + /* Get the "official" set of cpus referring to our pagetable. */ + mask = mm->cpu_vm_mask; + + /* It's possible that a vcpu may have a stale reference to our + cr3, because its in lazy mode, and it hasn't yet flushed + its set of pending hypercalls yet. In this case, we can + look at its actual current cr3 value, and force it to flush + if needed. */ + for_each_online_cpu(cpu) { + if (per_cpu(xen_current_cr3, cpu) == __pa(mm->pgd)) + cpu_set(cpu, mask); } - if (!cpus_empty(mm->cpu_vm_mask)) - xen_smp_call_function_mask(mm->cpu_vm_mask, drop_other_mm_ref, - mm, 1); + if (!cpus_empty(mask)) + xen_smp_call_function_mask(mask, drop_other_mm_ref, mm, 1); } #else static void drop_mm_ref(struct mm_struct *mm) |