From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:37186 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030519AbcDLVAf (ORCPT ); Tue, 12 Apr 2016 17:00:35 -0400 Subject: Patch "parisc: Unbreak handling exceptions from kernel modules" has been added to the 4.4-stable tree To: deller@gmx.de, gregkh@linuxfoundation.org, mpatocka@redhat.com Cc: , From: Date: Tue, 12 Apr 2016 14:00:33 -0700 Message-ID: <146049483396214@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 parisc: Unbreak handling exceptions from kernel modules 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: parisc-unbreak-handling-exceptions-from-kernel-modules.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 2ef4dfd9d9f288943e249b78365a69e3ea3ec072 Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Fri, 8 Apr 2016 18:32:52 +0200 Subject: parisc: Unbreak handling exceptions from kernel modules From: Helge Deller commit 2ef4dfd9d9f288943e249b78365a69e3ea3ec072 upstream. Handling exceptions from modules never worked on parisc. It was just masked by the fact that exceptions from modules don't happen during normal use. When a module triggers an exception in get_user() we need to load the main kernel dp value before accessing the exception_data structure, and afterwards restore the original dp value of the module on exit. Noticed-by: Mikulas Patocka Signed-off-by: Helge Deller Signed-off-by: Greg Kroah-Hartman --- arch/parisc/include/asm/uaccess.h | 1 + arch/parisc/kernel/asm-offsets.c | 1 + arch/parisc/lib/fixup.S | 6 ++++++ arch/parisc/mm/fault.c | 1 + 4 files changed, 9 insertions(+) --- a/arch/parisc/include/asm/uaccess.h +++ b/arch/parisc/include/asm/uaccess.h @@ -76,6 +76,7 @@ struct exception_table_entry { */ struct exception_data { unsigned long fault_ip; + unsigned long fault_gp; unsigned long fault_space; unsigned long fault_addr; }; --- a/arch/parisc/kernel/asm-offsets.c +++ b/arch/parisc/kernel/asm-offsets.c @@ -299,6 +299,7 @@ int main(void) #endif BLANK(); DEFINE(EXCDATA_IP, offsetof(struct exception_data, fault_ip)); + DEFINE(EXCDATA_GP, offsetof(struct exception_data, fault_gp)); DEFINE(EXCDATA_SPACE, offsetof(struct exception_data, fault_space)); DEFINE(EXCDATA_ADDR, offsetof(struct exception_data, fault_addr)); BLANK(); --- a/arch/parisc/lib/fixup.S +++ b/arch/parisc/lib/fixup.S @@ -26,6 +26,7 @@ #ifdef CONFIG_SMP .macro get_fault_ip t1 t2 + loadgp addil LT%__per_cpu_offset,%r27 LDREG RT%__per_cpu_offset(%r1),\t1 /* t2 = smp_processor_id() */ @@ -40,14 +41,19 @@ LDREG RT%exception_data(%r1),\t1 /* t1 = this_cpu_ptr(&exception_data) */ add,l \t1,\t2,\t1 + /* %r27 = t1->fault_gp - restore gp */ + LDREG EXCDATA_GP(\t1), %r27 /* t1 = t1->fault_ip */ LDREG EXCDATA_IP(\t1), \t1 .endm #else .macro get_fault_ip t1 t2 + loadgp /* t1 = this_cpu_ptr(&exception_data) */ addil LT%exception_data,%r27 LDREG RT%exception_data(%r1),\t2 + /* %r27 = t2->fault_gp - restore gp */ + LDREG EXCDATA_GP(\t2), %r27 /* t1 = t2->fault_ip */ LDREG EXCDATA_IP(\t2), \t1 .endm --- a/arch/parisc/mm/fault.c +++ b/arch/parisc/mm/fault.c @@ -151,6 +151,7 @@ int fixup_exception(struct pt_regs *regs struct exception_data *d; d = this_cpu_ptr(&exception_data); d->fault_ip = regs->iaoq[0]; + d->fault_gp = regs->gr[27]; d->fault_space = regs->isr; d->fault_addr = regs->ior; Patches currently in stable-queue which might be from deller@gmx.de are queue-4.4/parisc-fix-kernel-crash-with-reversed-copy_from_user.patch queue-4.4/parisc-unbreak-handling-exceptions-from-kernel-modules.patch queue-4.4/parisc-avoid-function-pointers-for-kernel-exception-routines.patch