| From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> |
| Date: Mon, 11 Mar 2013 17:09:55 +0100 |
| Subject: x86/highmem: Add a "already used pte" check |
| |
| This is a copy from kmap_atomic_prot(). |
| |
| Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> |
| --- |
| arch/x86/mm/iomap_32.c | 2 ++ |
| 1 file changed, 2 insertions(+) |
| |
| --- a/arch/x86/mm/iomap_32.c |
| +++ b/arch/x86/mm/iomap_32.c |
| @@ -66,6 +66,8 @@ void *kmap_atomic_prot_pfn(unsigned long |
| type = kmap_atomic_idx_push(); |
| idx = type + KM_TYPE_NR * smp_processor_id(); |
| vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); |
| + WARN_ON(!pte_none(*(kmap_pte - idx))); |
| + |
| #ifdef CONFIG_PREEMPT_RT_FULL |
| current->kmap_pte[type] = pte; |
| #endif |