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=-13.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 8B4A7C433B4 for ; Wed, 19 May 2021 14:42:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 649926124C for ; Wed, 19 May 2021 14:42:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242635AbhESOnd (ORCPT ); Wed, 19 May 2021 10:43:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44394 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240638AbhESOnd (ORCPT ); Wed, 19 May 2021 10:43:33 -0400 Received: from smtp.gentoo.org (mail.gentoo.org [IPv6:2001:470:ea4a:1:5054:ff:fec7:86e4]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 68A0DC06175F for ; Wed, 19 May 2021 07:42:13 -0700 (PDT) Received: by sf.home (Postfix, from userid 1000) id DA22D5A22061; Wed, 19 May 2021 15:42:06 +0100 (BST) Date: Wed, 19 May 2021 15:42:06 +0100 From: Sergei Trofimovich To: Christoph Hellwig Cc: Chris Wilson , Daniel Vetter , Jani Nikula , Joonas Lahtinen , Peter Zijlstra , Rodrigo Vivi , linux-kernel@vger.kernel.org Subject: [bisected] 5.13-rc2 i915 regression in b12d691ea5e01d "i915: fix remap_io_sg to verify the pgprot" Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Christoph and i915 maintainers! vanilla 5.13-rc2 got some rendering regression on gen2(?) i915 chips: In gtk apps cursor gets corrupted for a short period of time. In firefox text selection and text scrolling shows artifacts for a short time (seconds). As if tiny horisontal tiles (1 pixel high, ~20-50 pixels long) fail to refresh in time. I was not able get a screenshot with artifacts: pictures are always clean. I can grab a photo or tiny video if needed. Bisection was straightforward and landed on: b12d691ea5e01db42ccf3b4207e57cb3ce7cfe91 is the first bad commit commit b12d691ea5e01db42ccf3b4207e57cb3ce7cfe91 Author: Christoph Hellwig Date: Thu Apr 29 22:57:38 2021 -0700 i915: fix remap_io_sg to verify the pgprot remap_io_sg claims that the pgprot is pre-verified using an io_mapping, but actually does not get passed an io_mapping and just uses the pgprot in the VMA. Remove the apply_to_page_range abuse and just loop over remap_pfn_range for each segment. Note: this could use io_mapping_map_user by passing an iomap to remap_io_sg if the maintainers can verify that the pgprot in the iomap in the only caller is indeed the desired one here. Link: https://lkml.kernel.org/r/20210326055505.1424432-5-hch@lst.de Signed-off-by: Christoph Hellwig Cc: Chris Wilson Cc: Daniel Vetter Cc: Jani Nikula Cc: Joonas Lahtinen Cc: Peter Zijlstra Cc: Rodrigo Vivi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds drivers/gpu/drm/i915/i915_mm.c | 73 +++++++++++++----------------------------- 1 file changed, 23 insertions(+), 50 deletions(-) System: $ Linux sf 5.12.0-11146-g8ca5297e7e38 #302 SMP PREEMPT Thu Apr 29 23:30:52 BST 2021 x86_64 Intel(R) Core(TM) i7-2700K CPU @ 3.50GHz GenuineIntel GNU/Linux $ lspci -v 00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) (prog-if 00 [VGA controller]) Subsystem: Gigabyte Technology Co., Ltd 2nd Generation Core Processor Family Integrated Graphics Controller Flags: bus master, fast devsel, latency 0, IRQ 27 Memory at f7800000 (64-bit, non-prefetchable) [size=4M] Memory at e0000000 (64-bit, prefetchable) [size=256M] I/O ports at f000 [size=64] Expansion ROM at 000c0000 [virtual] [disabled] [size=128K] Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit- Capabilities: [d0] Power Management version 2 Capabilities: [a4] PCI Advanced Features Kernel driver in use: i915 Software: mesa-20.3.5 : i965 driver glamor X acceleration enabled on Mesa DRI Intel(R) HD Graphics 3000 (SNB GT2) xorg-server-1.20.11 Thanks! -- Sergei