From 3b17979bda74493633364c2c263b452b7788e350 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 6 Dec 2006 20:32:22 -0800 Subject: [PATCH] [PATCH] Fix kunmap_atomic's use of kpte_clear_flush() kunmap_atomic() will call kpte_clear_flush with vaddr/ptep arguments which don't correspond if the vaddr is just a normal lowmem address (ie, not in the KMAP area). This patch makes sure that the pte is only cleared if kmap area was actually used for the mapping. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Rusty Russell Cc: Zachary Amsden Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/mm/highmem.c | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-) diff --git a/arch/i386/mm/highmem.c b/arch/i386/mm/highmem.c index 178bbfe6cbac..e0fa6cb655a8 100644 --- a/arch/i386/mm/highmem.c +++ b/arch/i386/mm/highmem.c @@ -50,22 +50,20 @@ void kunmap_atomic(void *kvaddr, enum km_type type) unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id(); -#ifdef CONFIG_DEBUG_HIGHMEM - if (vaddr >= PAGE_OFFSET && vaddr < (unsigned long)high_memory) { - pagefault_enable(); - return; - } - - if (vaddr != __fix_to_virt(FIX_KMAP_BEGIN+idx)) - BUG(); -#endif /* * Force other mappings to Oops if they'll try to access this pte * without first remap it. Keeping stale mappings around is a bad idea * also, in case the page changes cacheability attributes or becomes * a protected page in a hypervisor. */ - kpte_clear_flush(kmap_pte-idx, vaddr); + if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx)) + kpte_clear_flush(kmap_pte-idx, vaddr); + else { +#ifdef CONFIG_DEBUG_HIGHMEM + BUG_ON(vaddr < PAGE_OFFSET); + BUG_ON(vaddr >= (unsigned long)high_memory); +#endif + } pagefault_enable(); } -- 2.30.2