diff --git a/arch/loongarch/kernel/vdso.c b/arch/loongarch/kernel/vdso.c index 59aa9dd466e8..64eb5386e7b2 100644 --- a/arch/loongarch/kernel/vdso.c +++ b/arch/loongarch/kernel/vdso.c @@ -40,6 +40,8 @@ static struct page *vdso_pages[] = { NULL }; struct vdso_data *vdso_data = generic_vdso_data.data; struct vdso_pcpu_data *vdso_pdata = loongarch_vdso_data.vdata.pdata; +static struct page *find_timens_vvar_page(struct vm_area_struct *vma); + static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma) { current->mm->context.vdso = (void *)(new_vma->vm_start); @@ -139,13 +141,37 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns) mmap_read_lock(mm); for_each_vma(vmi, vma) { + unsigned long size = vma->vm_end - vma->vm_start; + if (vma_is_special_mapping(vma, &vdso_info.data_mapping)) - zap_vma_pages(vma); + zap_page_range(vma, vma->vm_start, size); } mmap_read_unlock(mm); return 0; } + +static struct page *find_timens_vvar_page(struct vm_area_struct *vma) +{ + if (likely(vma->vm_mm == current->mm)) + return current->nsproxy->time_ns->vvar_page; + + /* + * VM_PFNMAP | VM_IO protect .fault() handler from being called + * through interfaces like /proc/$pid/mem or + * process_vm_{readv,writev}() as long as there's no .access() + * in special_mapping_vmops. + * For more details check_vma_flags() and __access_remote_vm() + */ + WARN(1, "vvar_page accessed remotely"); + + return NULL; +} +#else +static struct page *find_timens_vvar_page(struct vm_area_struct *vma) +{ + return NULL; +} #endif static unsigned long vdso_base(void)