From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:58556 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756894AbdCHHDv (ORCPT ); Wed, 8 Mar 2017 02:03:51 -0500 Subject: Patch "MIPS: Clear ISA bit correctly in get_frame_info()" has been added to the 4.4-stable tree To: paul.burton@imgtec.com, gregkh@linuxfoundation.org, leonid.yegoshin@imgtec.com, ralf@linux-mips.org Cc: , From: Date: Wed, 08 Mar 2017 07:59:35 +0100 Message-ID: <148895637522226@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled MIPS: Clear ISA bit correctly in get_frame_info() to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mips-clear-isa-bit-correctly-in-get_frame_info.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From ccaf7caf2c73c6db920772bf08bf1d47b2170634 Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Mon, 7 Nov 2016 15:07:02 +0000 Subject: MIPS: Clear ISA bit correctly in get_frame_info() From: Paul Burton commit ccaf7caf2c73c6db920772bf08bf1d47b2170634 upstream. get_frame_info() can be called in microMIPS kernels with the ISA bit already clear. For example this happens when unwind_stack_by_address() is called because we begin with a PC that has the ISA bit set & subtract the (odd) offset from the preceding symbol (which does not have the ISA bit set). Since get_frame_info() unconditionally subtracts 1 from the PC in microMIPS kernels it incorrectly misaligns the address it then attempts to access code at, leading to an address error exception. Fix this by using msk_isa16_mode() to clear the ISA bit, which allows get_frame_info() to function regardless of whether it is provided with a PC that has the ISA bit set or not. Signed-off-by: Paul Burton Fixes: 34c2f668d0f6 ("MIPS: microMIPS: Add unaligned access support.") Cc: Leonid Yegoshin Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/14528/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman --- arch/mips/kernel/process.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -299,17 +299,14 @@ static inline int is_sp_move_ins(union m static int get_frame_info(struct mips_frame_info *info) { -#ifdef CONFIG_CPU_MICROMIPS - union mips_instruction *ip = (void *) (((char *) info->func) - 1); -#else - union mips_instruction *ip = info->func; -#endif + union mips_instruction *ip; unsigned max_insns = info->func_size / sizeof(union mips_instruction); unsigned i; info->pc_offset = -1; info->frame_size = 0; + ip = (void *)msk_isa16_mode((ulong)info->func); if (!ip) goto err; Patches currently in stable-queue which might be from paul.burton@imgtec.com are queue-4.4/mips-calculate-micromips-ra-properly-when-unwinding-the-stack.patch queue-4.4/mips-fix-get_frame_info-handling-of-micromips-function-size.patch queue-4.4/mips-handle-micromips-jumps-in-the-same-way-as-mips32-mips64-jumps.patch queue-4.4/mips-fix-is_jump_ins-handling-of-16b-micromips-instructions.patch queue-4.4/mips-clear-isa-bit-correctly-in-get_frame_info.patch queue-4.4/mips-prevent-unaligned-accesses-during-stack-unwinding.patch