diff options
| -rw-r--r-- | mm/hmm.c | 36 |
1 files changed, 21 insertions, 15 deletions
@@ -91,16 +91,6 @@ static struct hmm *hmm_register(struct mm_struct *mm) spin_lock_init(&hmm->lock); hmm->mm = mm; - /* - * We should only get here if hold the mmap_sem in write mode ie on - * registration of first mirror through hmm_mirror_register() - */ - hmm->mmu_notifier.ops = &hmm_mmu_notifier_ops; - if (__mmu_notifier_register(&hmm->mmu_notifier, mm)) { - kfree(hmm); - return NULL; - } - spin_lock(&mm->page_table_lock); if (!mm->hmm) mm->hmm = hmm; @@ -108,12 +98,27 @@ static struct hmm *hmm_register(struct mm_struct *mm) cleanup = true; spin_unlock(&mm->page_table_lock); - if (cleanup) { - mmu_notifier_unregister(&hmm->mmu_notifier, mm); - kfree(hmm); - } + if (cleanup) + goto error; + + /* + * We should only get here if hold the mmap_sem in write mode ie on + * registration of first mirror through hmm_mirror_register() + */ + hmm->mmu_notifier.ops = &hmm_mmu_notifier_ops; + if (__mmu_notifier_register(&hmm->mmu_notifier, mm)) + goto error_mm; return mm->hmm; + +error_mm: + spin_lock(&mm->page_table_lock); + if (mm->hmm == hmm) + mm->hmm = NULL; + spin_unlock(&mm->page_table_lock); +error: + kfree(hmm); + return NULL; } void hmm_mm_destroy(struct mm_struct *mm) @@ -278,12 +283,13 @@ void hmm_mirror_unregister(struct hmm_mirror *mirror) if (!should_unregister || mm == NULL) return; + mmu_notifier_unregister_no_release(&hmm->mmu_notifier, mm); + spin_lock(&mm->page_table_lock); if (mm->hmm == hmm) mm->hmm = NULL; spin_unlock(&mm->page_table_lock); - mmu_notifier_unregister_no_release(&hmm->mmu_notifier, mm); kfree(hmm); } EXPORT_SYMBOL(hmm_mirror_unregister); |