From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:39060 "EHLO mx0b-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727540AbgIOR1H (ORCPT ); Tue, 15 Sep 2020 13:27:07 -0400 From: Heiko Carstens Subject: [PATCH 2/4] s390/dis: get rid of set_fs() usage Date: Tue, 15 Sep 2020 17:43:38 +0200 Message-Id: <20200915154340.4215-3-hca@linux.ibm.com> In-Reply-To: <20200915154340.4215-1-hca@linux.ibm.com> References: <20200915154340.4215-1-hca@linux.ibm.com> Sender: linux-s390-owner@vger.kernel.org List-ID: To: Christoph Hellwig Cc: Vasily Gorbik , Christian Borntraeger , Harald Freudenberger , linux-s390@vger.kernel.org Signed-off-by: Heiko Carstens --- arch/s390/kernel/dis.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/arch/s390/kernel/dis.c b/arch/s390/kernel/dis.c index f304802ecf7b..68bf2e9ebe5a 100644 --- a/arch/s390/kernel/dis.c +++ b/arch/s390/kernel/dis.c @@ -487,26 +487,30 @@ void show_code(struct pt_regs *regs) char *mode = user_mode(regs) ? "User" : "Krnl"; unsigned char code[64]; char buffer[128], *ptr; - mm_segment_t old_fs; unsigned long addr; int start, end, opsize, hops, i; /* Get a snapshot of the 64 bytes surrounding the fault address. */ - old_fs = get_fs(); - set_fs(user_mode(regs) ? USER_DS : KERNEL_DS); for (start = 32; start && regs->psw.addr >= 34 - start; start -= 2) { addr = regs->psw.addr - 34 + start; - if (__copy_from_user(code + start - 2, - (char __user *) addr, 2)) - break; + if (user_mode(regs)) { + if (__copy_from_user(code + start - 2, (char __user *)addr, 2)) + break; + } else { + if (copy_from_kernel_nofault(code + start - 2, (char *)addr, 2)) + break; + } } for (end = 32; end < 64; end += 2) { addr = regs->psw.addr + end - 32; - if (__copy_from_user(code + end, - (char __user *) addr, 2)) - break; + if (user_mode(regs)) { + if (__copy_from_user(code + end, (char __user *)addr, 2)) + break; + } else { + if (copy_from_kernel_nofault(code + end, (char *)addr, 2)) + break; + } } - set_fs(old_fs); /* Code snapshot useable ? */ if ((regs->psw.addr & 1) || start >= end) { printk("%s Code: Bad PSW.\n", mode); -- 2.17.1