From 2ace05044cab3c7cf2a6d143b5927d47f3a9dc0a Mon Sep 17 00:00:00 2001 From: Andreas Sandberg Date: Thu, 26 May 2016 17:38:15 +0100 Subject: [PATCH] arm: Fix incorrect TLB permission check in aarch32 The TLB currently assumes that the pxn bit in an LPAE page descriptor disables execution from unprivileged mode. However, according to the architecture manual, this bit should disable execution from privileged modes. Update the TLB implementation to reflect this behavior. Change-Id: I7f1bb232d7a94a93fd601a9230223195ac952947 Signed-off-by: Andreas Sandberg Reviewed-by: Nikos Nikoleris --- src/arch/arm/tlb.cc | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/arch/arm/tlb.cc b/src/arch/arm/tlb.cc index 1bce0f798..3fc317048 100644 --- a/src/arch/arm/tlb.cc +++ b/src/arch/arm/tlb.cc @@ -1,5 +1,5 @@ /* - * Copyright (c) 2010-2013 ARM Limited + * Copyright (c) 2010-2013, 2016 ARM Limited * All rights reserved * * The license below extends only to copyright in the software and shall @@ -720,7 +720,7 @@ TLB::checkPermissions(TlbEntry *te, RequestPtr req, Mode mode) bool xn = te->xn || (isWritable && sctlr.wxn) || (ap == 3 && sctlr.uwxn && is_priv); if (is_fetch && (abt || xn || - (te->longDescFormat && te->pxn && !is_priv) || + (te->longDescFormat && te->pxn && is_priv) || (isSecure && te->ns && scr.sif))) { permsFaults++; DPRINTF(TLB, "TLB Fault: Prefetch abort on permission check. AP:%d " -- 2.30.2