From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7359CC28EBD for ; Sun, 9 Jun 2019 16:54:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 41021205ED for ; Sun, 9 Jun 2019 16:54:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560099276; bh=lelvo0io8nkp8qWK8JdAYNl7dl/qXAIZPC9tzGmuaNI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=EW0pcEVqyulfy9gk7BTXvHnbsdvwzqRl1Lf8mOIaWSoCXUrduJEr5MitmnAaYye2a 9fwXGJjLH468Kmf4Qd9zbXs/y2Ill7qwozun9rhMno0jCqT3vDUS89XF7BKa358kG5 iHyRCKuYVoftmAS0uDr/mhnbdepZcc4s7x6AX69s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732642AbfFIQyf (ORCPT ); Sun, 9 Jun 2019 12:54:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:56278 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732624AbfFIQye (ORCPT ); Sun, 9 Jun 2019 12:54:34 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 08989206BB; Sun, 9 Jun 2019 16:54:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560099273; bh=lelvo0io8nkp8qWK8JdAYNl7dl/qXAIZPC9tzGmuaNI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cQUyxEqgzJYe2QrdJXddM0e/WzNF7Xb5oueKAlPYxJCqCAw6fzIXxnnGM8KgFTPzo PRXqLPFwv34PquN4oOawsqzg8YZWagEQ9Mhf4XXrA2iIbyIJ76GPNTVJfNU5bbFrcB 51iTmNgD3TI4k0D4qhVg4j1mHofCwuRXBkBlRWE0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, John David Anglin , Helge Deller Subject: [PATCH 4.9 72/83] parisc: Use implicit space register selection for loading the coherence index of I/O pdirs Date: Sun, 9 Jun 2019 18:42:42 +0200 Message-Id: <20190609164133.991775459@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190609164127.843327870@linuxfoundation.org> References: <20190609164127.843327870@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: John David Anglin commit 63923d2c3800919774f5c651d503d1dd2adaddd5 upstream. We only support I/O to kernel space. Using %sr1 to load the coherence index may be racy unless interrupts are disabled. This patch changes the code used to load the coherence index to use implicit space register selection. This saves one instruction and eliminates the race. Tested on rp3440, c8000 and c3750. Signed-off-by: John David Anglin Cc: stable@vger.kernel.org Signed-off-by: Helge Deller Signed-off-by: Greg Kroah-Hartman --- drivers/parisc/ccio-dma.c | 4 +--- drivers/parisc/sba_iommu.c | 3 +-- 2 files changed, 2 insertions(+), 5 deletions(-) --- a/drivers/parisc/ccio-dma.c +++ b/drivers/parisc/ccio-dma.c @@ -563,8 +563,6 @@ ccio_io_pdir_entry(u64 *pdir_ptr, space_ /* We currently only support kernel addresses */ BUG_ON(sid != KERNEL_SPACE); - mtsp(sid,1); - /* ** WORD 1 - low order word ** "hints" parm includes the VALID bit! @@ -595,7 +593,7 @@ ccio_io_pdir_entry(u64 *pdir_ptr, space_ ** Grab virtual index [0:11] ** Deposit virt_idx bits into I/O PDIR word */ - asm volatile ("lci %%r0(%%sr1, %1), %0" : "=r" (ci) : "r" (vba)); + asm volatile ("lci %%r0(%1), %0" : "=r" (ci) : "r" (vba)); asm volatile ("extru %1,19,12,%0" : "+r" (ci) : "r" (ci)); asm volatile ("depw %1,15,12,%0" : "+r" (pa) : "r" (ci)); --- a/drivers/parisc/sba_iommu.c +++ b/drivers/parisc/sba_iommu.c @@ -573,8 +573,7 @@ sba_io_pdir_entry(u64 *pdir_ptr, space_t pa = virt_to_phys(vba); pa &= IOVP_MASK; - mtsp(sid,1); - asm("lci 0(%%sr1, %1), %0" : "=r" (ci) : "r" (vba)); + asm("lci 0(%1), %0" : "=r" (ci) : "r" (vba)); pa |= (ci >> PAGE_SHIFT) & 0xff; /* move CI (8 bits) into lowest byte */ pa |= SBA_PDIR_VALID_BIT; /* set "valid" bit */