Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933584AbbDII5X (ORCPT ); Thu, 9 Apr 2015 04:57:23 -0400 Received: from mail.kernel.org ([198.145.29.136]:43413 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932759AbbDII5Q (ORCPT ); Thu, 9 Apr 2015 04:57:16 -0400 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, David Daney , Leonid Yegoshin , linux-mips@linux-mips.org, Ralf Baechle , Zefan Li Subject: [PATCH 3.4 145/176] MIPS: Fix C0_Pagegrain[IEC] support. Date: Thu, 9 Apr 2015 16:46:33 +0800 Message-Id: <1428569224-23820-145-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1428569028-23762-1-git-send-email-lizf@kernel.org> References: <1428569028-23762-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1959 Lines: 58 From: David Daney 3.4.107-rc1 review patch. If anyone has any objections, please let me know. ------------------ commit 9ead8632bbf454cfc709b6205dc9cd8582fb0d64 upstream. The following commits: 5890f70f15c52d (MIPS: Use dedicated exception handler if CPU supports RI/XI exceptions) 6575b1d4173eae (MIPS: kernel: cpu-probe: Detect unique RI/XI exceptions) break the kernel for *all* existing MIPS CPUs that implement the CP0_PageGrain[IEC] bit. They cause the TLB exception handlers to be generated without the legacy execute-inhibit handling, but never set the CP0_PageGrain[IEC] bit to activate the use of dedicated exception vectors for execute-inhibit exceptions. The result is that upon detection of an execute-inhibit violation, we loop forever in the TLB exception handlers instead of sending SIGSEGV to the task. If we are generating TLB exception handlers expecting separate vectors, we must also enable the CP0_PageGrain[IEC] feature. The bug was introduced in kernel version 3.17. Signed-off-by: David Daney Cc: Leonid Yegoshin Cc: linux-mips@linux-mips.org Patchwork: http://patchwork.linux-mips.org/patch/8880/ Signed-off-by: Ralf Baechle Signed-off-by: Zefan Li --- arch/mips/mm/tlb-r4k.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c index d2572cb..6ac2e87 100644 --- a/arch/mips/mm/tlb-r4k.c +++ b/arch/mips/mm/tlb-r4k.c @@ -410,6 +410,8 @@ void __cpuinit tlb_init(void) #ifdef CONFIG_64BIT pg |= PG_ELPA; #endif + if (cpu_has_rixiex) + pg |= PG_IEC; write_c0_pagegrain(pg); } -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/