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 2369AC28EBD for ; Sun, 9 Jun 2019 16:50:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ED9C9207E0 for ; Sun, 9 Jun 2019 16:50:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560099008; bh=g+hd2iLdmdvsV99V+ur7k869hgf102FOOHf4hvs7/pY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=sWTkLCOIfITgvqptJiGXp4sC2NSOhsX0D8SjOdwOuZHhaT0lyTD4OvYkCLFhI9kgv SEl9ZD/ecc5qvr/PACOe+i4IaLnyxWcRlBmShhl5L8vpiUpUFpsmWrE9cwXJgAa/WN G54vcLNUUE7W2rWdAXRnIzDm7J67//eEl0k5b5+k= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731645AbfFIQuG (ORCPT ); Sun, 9 Jun 2019 12:50:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:49800 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731623AbfFIQuC (ORCPT ); Sun, 9 Jun 2019 12:50:02 -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 6AA96205ED; Sun, 9 Jun 2019 16:50:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560099001; bh=g+hd2iLdmdvsV99V+ur7k869hgf102FOOHf4hvs7/pY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wyKWgqFyfU1DUNVrI4cZxFn/PuarliIEUqBw3Kv7w3DmVOIMa+DieWG4Hk5bJEbqy DV0uNniW3CqME6L7PpKn63LIz/YkFQHpfDh/d0pTqzLpVZ6kqE38wNOU/Qaz6qAdmD JH4/TxVcm/RqLdOLhFW4gwxLtH2ogz4s7rECiPlE= 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 4.14 14/35] parisc: Use implicit space register selection for loading the coherence index of I/O pdirs Date: Sun, 9 Jun 2019 18:42:20 +0200 Message-Id: <20190609164126.324583755@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190609164125.377368385@linuxfoundation.org> References: <20190609164125.377368385@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 @@ -565,8 +565,6 @@ 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! @@ -597,7 +595,7 @@ 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 @@ -575,8 +575,7 @@ 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 */