From: Christophe Leroy Date: Tue, 9 Feb 2016 16:07:56 +0000 (+0100) Subject: powerpc32: Fix pte_offset_kernel() to return NULL for bad pages X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=be00ed728c32ed8311d5191637067c9eaf0fca4b;p=linux-beck.git powerpc32: Fix pte_offset_kernel() to return NULL for bad pages The fixmap related functions try to map kernel pages that are already mapped through Large TLBs. pte_offset_kernel() has to return NULL for LTLBs, otherwise the caller will try to access level 2 table which doesn't exist Signed-off-by: Christophe Leroy Signed-off-by: Scott Wood --- diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h index c82cbf52d19e..e2016007c04e 100644 --- a/arch/powerpc/include/asm/nohash/32/pgtable.h +++ b/arch/powerpc/include/asm/nohash/32/pgtable.h @@ -309,7 +309,8 @@ static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry) #define pte_index(address) \ (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) #define pte_offset_kernel(dir, addr) \ - ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(addr)) + (pmd_bad(*(dir)) ? NULL : (pte_t *)pmd_page_vaddr(*(dir)) + \ + pte_index(addr)) #define pte_offset_map(dir, addr) \ ((pte_t *) kmap_atomic(pmd_page(*(dir))) + pte_index(addr)) #define pte_unmap(pte) kunmap_atomic(pte)