diff options
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/mm/pgtable.c | 22 |
1 files changed, 7 insertions, 15 deletions
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c index ea4a31b95990..66ba60c9b77e 100644 --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -958,8 +958,10 @@ void page_table_reset_pgste(struct mm_struct *mm, unsigned long start, unsigned long addr, next; pgd_t *pgd; + down_write(&mm->mmap_sem); + if (init_skey && mm_use_skey(mm)) + goto out_up; addr = start; - down_read(&mm->mmap_sem); pgd = pgd_offset(mm, addr); do { next = pgd_addr_end(addr, end); @@ -967,7 +969,10 @@ void page_table_reset_pgste(struct mm_struct *mm, unsigned long start, continue; next = page_table_reset_pud(mm, pgd, addr, next, init_skey); } while (pgd++, addr = next, addr != end); - up_read(&mm->mmap_sem); + if (init_skey) + current->mm->context.use_skey = 1; +out_up: + up_write(&mm->mmap_sem); } EXPORT_SYMBOL(page_table_reset_pgste); @@ -1384,19 +1389,6 @@ EXPORT_SYMBOL_GPL(s390_enable_sie); */ void s390_enable_skey(void) { - /* - * To avoid races between multiple vcpus, ending in calling - * page_table_reset twice or more, - * the page_table_lock is taken for serialization. - */ - spin_lock(¤t->mm->page_table_lock); - if (mm_use_skey(current->mm)) { - spin_unlock(¤t->mm->page_table_lock); - return; - } - - current->mm->context.use_skey = 1; - spin_unlock(¤t->mm->page_table_lock); page_table_reset_pgste(current->mm, 0, TASK_SIZE, true); } EXPORT_SYMBOL_GPL(s390_enable_skey); |