From e4eab1ce1f679507c02ea48e6b6edaef33f8fee3 Mon Sep 17 00:00:00 2001 From: Sven Schnelle Date: Wed, 5 Jun 2019 22:32:19 +0200 Subject: [PATCH] parisc: add WARN_ON() to clear_fixmap Calling clear_fixmap() on an already cleared fixed mapping is a bad thing to do. Add a WARN_ON() to catch such issues. Signed-off-by: Sven Schnelle Signed-off-by: Helge Deller --- arch/parisc/mm/fixmap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/parisc/mm/fixmap.c b/arch/parisc/mm/fixmap.c index c8d41b54fb19..36321bcd75ba 100644 --- a/arch/parisc/mm/fixmap.c +++ b/arch/parisc/mm/fixmap.c @@ -35,6 +35,9 @@ void clear_fixmap(enum fixed_addresses idx) pmd_t *pmd = pmd_offset(pgd, vaddr); pte_t *pte = pte_offset_kernel(pmd, vaddr); + if (WARN_ON(pte_none(*pte))) + return; + pte_clear(&init_mm, vaddr, pte); flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE); -- 2.30.2