From 9690c15742688e9cb5ee4aa0b08e458551ceea13 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Thu, 2 Jun 2016 15:14:48 +0530 Subject: [PATCH] powerpc/mm/radix: Fix always false comparison against MMU_NO_CONTEXT In some of the radix TLB flush routines, we use a local to store the mm->context.id, AKA the PID. Currently we use an int, but the PID is unsigned long, so large values of PID will be truncated. In particular MMU_NO_CONTEXT is -1, which means all our comparisons against that value can never be true. This means we'll issue TLB flushes when we shouldn't on radix enabled machines. Fix it by using an unsigned long for the local. Discovered by Coverity. Fixes: 1a472c9dba6b ("powerpc/mm/radix: Add tlbflush routines") Signed-off-by: Aneesh Kumar K.V Reviewed-by: Balbir Singh [mpe: Write change log] Signed-off-by: Michael Ellerman --- arch/powerpc/mm/tlb-radix.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/mm/tlb-radix.c b/arch/powerpc/mm/tlb-radix.c index 0fdaf93..54efba2 100644 --- a/arch/powerpc/mm/tlb-radix.c +++ b/arch/powerpc/mm/tlb-radix.c @@ -117,7 +117,7 @@ static inline void _tlbie_va(unsigned long va, unsigned long pid, */ void radix__local_flush_tlb_mm(struct mm_struct *mm) { - unsigned int pid; + unsigned long pid; preempt_disable(); pid = mm->context.id; @@ -130,7 +130,7 @@ EXPORT_SYMBOL(radix__local_flush_tlb_mm); void radix___local_flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr, unsigned long ap, int nid) { - unsigned int pid; + unsigned long pid; preempt_disable(); pid = mm ? mm->context.id : 0; @@ -160,7 +160,7 @@ static int mm_is_core_local(struct mm_struct *mm) void radix__flush_tlb_mm(struct mm_struct *mm) { - unsigned int pid; + unsigned long pid; preempt_disable(); pid = mm->context.id; @@ -185,7 +185,7 @@ EXPORT_SYMBOL(radix__flush_tlb_mm); void radix___flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr, unsigned long ap, int nid) { - unsigned int pid; + unsigned long pid; preempt_disable(); pid = mm ? mm->context.id : 0; -- 2.7.4