From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753798AbbHBAL7 (ORCPT ); Sat, 1 Aug 2015 20:11:59 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:36119 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751947AbbHBAJu (ORCPT ); Sat, 1 Aug 2015 20:09:50 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, vyasevich@gmail.com, boris.ostrovsky@oracle.com, siva.kallam@broadcom.com, "Ian Jackson" , sanjeevb@broadcom.com, "Linus Torvalds" , "Thomas Gleixner" , "Ingo Molnar" , "Prashant Sreedharan" , "David S. Miller" , xen-devel@lists.xensource.com, david.vrabel@citrix.com, "H. Peter Anvin" , "Konrad Rzeszutek Wilk" , "Michael Chan" , "Borislav Petkov" , cascardo@linux.vnet.ibm.com Date: Sun, 02 Aug 2015 01:02:38 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 144/164] config: Enable NEED_DMA_MAP_STATE by default when SWIOTLB is selected In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.70-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Konrad Rzeszutek Wilk commit a6dfa128ce5c414ab46b1d690f7a1b8decb8526d upstream. A huge amount of NIC drivers use the DMA API, however if compiled under 32-bit an very important part of the DMA API can be ommitted leading to the drivers not working at all (especially if used with 'swiotlb=force iommu=soft'). As Prashant Sreedharan explains it: "the driver [tg3] uses DEFINE_DMA_UNMAP_ADDR(), dma_unmap_addr_set() to keep a copy of the dma "mapping" and dma_unmap_addr() to get the "mapping" value. On most of the platforms this is a no-op, but ... with "iommu=soft and swiotlb=force" this house keeping is required, ... otherwise we pass 0 while calling pci_unmap_/pci_dma_sync_ instead of the DMA address." As such enable this even when using 32-bit kernels. Reported-by: Ian Jackson Signed-off-by: Konrad Rzeszutek Wilk Acked-by: David S. Miller Acked-by: Prashant Sreedharan Cc: Borislav Petkov Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Michael Chan Cc: Thomas Gleixner Cc: boris.ostrovsky@oracle.com Cc: cascardo@linux.vnet.ibm.com Cc: david.vrabel@citrix.com Cc: sanjeevb@broadcom.com Cc: siva.kallam@broadcom.com Cc: vyasevich@gmail.com Cc: xen-devel@lists.xensource.com Link: http://lkml.kernel.org/r/20150417190448.GA9462@l.oracle.com Signed-off-by: Ingo Molnar [bwh: Backported to 3.2: also change the def_bool (cond) to def_bool y + depends] Signed-off-by: Ben Hutchings --- arch/x86/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -133,7 +133,8 @@ config SBUS bool config NEED_DMA_MAP_STATE - def_bool (X86_64 || INTEL_IOMMU || DMA_API_DEBUG) + def_bool y + depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB config NEED_SG_DMA_LENGTH def_bool y