From patchwork Fri Mar 19 14:34:50 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 12151155 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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 A77EDC433DB for ; Fri, 19 Mar 2021 14:36:08 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2052964EE2 for ; Fri, 19 Mar 2021 14:36:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2052964EE2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id B01076B0070; Fri, 19 Mar 2021 10:36:07 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id AAD4E8D0001; Fri, 19 Mar 2021 10:36:07 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8B2626B0074; Fri, 19 Mar 2021 10:36:07 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0245.hostedemail.com [216.40.44.245]) by kanga.kvack.org (Postfix) with ESMTP id 60B166B0070 for ; Fri, 19 Mar 2021 10:36:07 -0400 (EDT) Received: from smtpin36.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 09C671801B5E9 for ; Fri, 19 Mar 2021 14:36:07 +0000 (UTC) X-FDA: 77936873532.36.ECE2DAC Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by imf04.hostedemail.com (Postfix) with ESMTP id 333FF7A7 for ; Fri, 19 Mar 2021 14:36:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1616164555; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WBpjOhjd+vmj4vtopl/ZTa7342hJ/aupO1u5xG6bHHA=; b=N0fhW12/G7YMyCp4PWhxEEN5Irh7YpbpVXr9OBSiHRDIOd61PYvqeNQ0jDmgjCHp9m6POq Popump+mQj/9D2jTZI2BDzNSm4cR0eckkV1yWllMlgtAa2RZJhnP7QjbVr+MXUbYAdDVh9 UTJsr0zBXK7rfxkm5xjuHFGheRenWWU= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-575-kwSHoBYePxSz9aJeiEKzFQ-1; Fri, 19 Mar 2021 10:35:53 -0400 X-MC-Unique: kwSHoBYePxSz9aJeiEKzFQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5EEEB1092F01; Fri, 19 Mar 2021 14:35:46 +0000 (UTC) Received: from t480s.redhat.com (ovpn-112-11.ams2.redhat.com [10.36.112.11]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7DE20610F4; Fri, 19 Mar 2021 14:35:24 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, David Hildenbrand , Andrew Morton , Hillf Danton , Michal Hocko , Matthew Wilcox , Oleksiy Avramchenko , Steven Rostedt , Minchan Kim , huang ying , Jonathan Corbet , Russell King , Liviu Dudau , Sudeep Holla , Lorenzo Pieralisi , Andrew Lunn , Gregory Clement , Sebastian Hesselbarth , Yoshinori Sato , Brian Cain , Geert Uytterhoeven , Jonas Bonn , Stefan Kristiansson , Stafford Horne , Rich Felker , "David S. Miller" , Chris Zankel , Max Filippov , Arnd Bergmann , Greg Kroah-Hartman , Alexander Viro , Rob Herring , "Pavel Machek (CIP)" , Theodore Dubois , "Alexander A. Klimov" , Pavel Machek , Sam Ravnborg , Alexandre Belloni , Andrey Zhizhikin , Randy Dunlap , Krzysztof Kozlowski , Viresh Kumar , "Eric W. Biederman" , Thomas Gleixner , Xiaoming Ni , Robert Richter , William Cohen , Corentin Labbe , Kairui Song , Linus Torvalds , linux-doc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, uclinux-h8-devel@lists.sourceforge.jp, linux-hexagon@vger.kernel.org, linux-m68k@lists.linux-m68k.org, openrisc@lists.librecores.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-xtensa@linux-xtensa.org, linux-fsdevel@vger.kernel.org, Linux API Subject: [PATCH RFC 1/3] drivers/char: remove /dev/kmem for good Date: Fri, 19 Mar 2021 15:34:50 +0100 Message-Id: <20210319143452.25948-2-david@redhat.com> In-Reply-To: <20210319143452.25948-1-david@redhat.com> References: <20210319143452.25948-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 333FF7A7 X-Stat-Signature: c5jkan95p6wmid76uwisf4tjp48d17ti Received-SPF: none (redhat.com>: No applicable sender policy available) receiver=imf04; identity=mailfrom; envelope-from=""; helo=us-smtp-delivery-124.mimecast.com; client-ip=216.205.24.124 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616164560-58791 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Exploring /dev/kmem and /dev/mem in the context of memory hot(un)plug and memory ballooning, I started questioning the existance of /dev/kmem. Comparing it with the /proc/kcore implementation, it does not seem to be able to deal with things like a) Pages unmapped from the direct mapping (e.g., to be used by secretmem) -> kern_addr_valid(). virt_addr_valid() is not sufficient. b) Special cases like gart aperture memory that is not to be touched -> mem_pfn_is_ram() Unless I am missing something, it's at least broken in some cases and might fault/crash the machine. Looks like its existance has been questioned before in 2005 and 2010 [1], after ~11 additional years, it might make sense to revive the discussion. CONFIG_DEVKMEM is only enabled in a single defconfig (on purpose or by mistake?). All distributions I looked at disable it. 1) /dev/kmem was popular for rootkits [2] before it got disabled basically everywhere. Ubuntu documents [3] "There is no modern user of /dev/kmem any more beyond attackers using it to load kernel rootkits.". RHEL documents in a BZ [5] "it served no practical purpose other than to serve as a potential security problem or to enable binary module drivers to access structures/functions they shouldn't be touching" 2) /proc/kcore is a decent interface to have a controlled way to read kernel memory for debugging puposes. (will need some extensions to deal with memory offlining/unplug, memory ballooning, and poisoned pages, though) 3) It might be useful for corner case debugging [1]. KDB/KGDB might be a better fit, especially, to write random memory; harder to shoot yourself into the foot. 4) "Kernel Memory Editor" hasn't seen any updates since 2000 and seems to be incompatible with 64bit [1]. For educational purposes, /proc/kcore might be used to monitor value updates -- or older kernels can be used. 5) It's broken on arm64, and therefore, completely disabled there. Looks like it's essentially unused and has been replaced by better suited interfaces for individual tasks (/proc/kcore, KDB/KGDB). Let's just remove it. [1] https://lwn.net/Articles/147901/ [2] https://www.linuxjournal.com/article/10505 [3] https://wiki.ubuntu.com/Security/Features#A.2Fdev.2Fkmem_disabled [4] https://sourceforge.net/projects/kme/ [5] https://bugzilla.redhat.com/show_bug.cgi?id=154796 Cc: Andrew Morton Cc: Hillf Danton Cc: Michal Hocko Cc: Matthew Wilcox Cc: Oleksiy Avramchenko Cc: Steven Rostedt Cc: Minchan Kim Cc: huang ying Cc: Jonathan Corbet Cc: Russell King Cc: Liviu Dudau Cc: Sudeep Holla Cc: Lorenzo Pieralisi Cc: Andrew Lunn Cc: Gregory Clement Cc: Sebastian Hesselbarth Cc: Yoshinori Sato Cc: Brian Cain Cc: Geert Uytterhoeven Cc: Jonas Bonn Cc: Stefan Kristiansson Cc: Stafford Horne Cc: Rich Felker Cc: "David S. Miller" Cc: Chris Zankel Cc: Max Filippov Cc: Arnd Bergmann Cc: Greg Kroah-Hartman Cc: Alexander Viro Cc: Rob Herring Cc: "Pavel Machek (CIP)" Cc: Theodore Dubois Cc: "Alexander A. Klimov" Cc: Pavel Machek Cc: Sam Ravnborg Cc: Alexandre Belloni Cc: Andrey Zhizhikin Cc: Randy Dunlap Cc: Krzysztof Kozlowski Cc: Viresh Kumar Cc: "Eric W. Biederman" Cc: Thomas Gleixner Cc: Xiaoming Ni Cc: Robert Richter Cc: William Cohen Cc: Corentin Labbe Cc: Kairui Song Cc: Linus Torvalds Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: uclinux-h8-devel@lists.sourceforge.jp Cc: linux-hexagon@vger.kernel.org Cc: linux-m68k@lists.linux-m68k.org Cc: openrisc@lists.librecores.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-fsdevel@vger.kernel.org Cc: Linux API Signed-off-by: David Hildenbrand Acked-by: Michal Hocko Acked-by: Kees Cook --- Documentation/admin-guide/devices.txt | 2 +- arch/arm/configs/dove_defconfig | 1 - arch/arm/configs/magician_defconfig | 1 - arch/arm/configs/moxart_defconfig | 1 - arch/arm/configs/mps2_defconfig | 1 - arch/arm/configs/mvebu_v5_defconfig | 1 - arch/arm/configs/xcep_defconfig | 1 - arch/h8300/configs/edosk2674_defconfig | 1 - arch/h8300/configs/h8300h-sim_defconfig | 1 - arch/h8300/configs/h8s-sim_defconfig | 1 - arch/hexagon/configs/comet_defconfig | 1 - arch/m68k/configs/amcore_defconfig | 1 - arch/openrisc/configs/or1ksim_defconfig | 1 - arch/sh/configs/edosk7705_defconfig | 1 - arch/sh/configs/se7206_defconfig | 1 - arch/sh/configs/sh2007_defconfig | 1 - arch/sh/configs/sh7724_generic_defconfig | 1 - arch/sh/configs/sh7770_generic_defconfig | 1 - arch/sh/configs/sh7785lcr_32bit_defconfig | 1 - arch/sparc/configs/sparc64_defconfig | 1 - arch/xtensa/configs/xip_kc705_defconfig | 1 - drivers/char/Kconfig | 10 - drivers/char/mem.c | 231 ---------------------- include/linux/fs.h | 2 +- include/linux/vmalloc.h | 2 +- kernel/configs/android-base.config | 1 - mm/ksm.c | 2 +- mm/vmalloc.c | 2 +- 28 files changed, 5 insertions(+), 267 deletions(-) diff --git a/Documentation/admin-guide/devices.txt b/Documentation/admin-guide/devices.txt index 63fd4e6a014b..beffd5e9130a 100644 --- a/Documentation/admin-guide/devices.txt +++ b/Documentation/admin-guide/devices.txt @@ -4,7 +4,7 @@ 1 char Memory devices 1 = /dev/mem Physical memory access - 2 = /dev/kmem Kernel virtual memory access + 2 = /dev/kmem OBSOLETE - replaced by /proc/kcore 3 = /dev/null Null device 4 = /dev/port I/O port access 5 = /dev/zero Null byte source diff --git a/arch/arm/configs/dove_defconfig b/arch/arm/configs/dove_defconfig index e70c997d5f4c..b935162a8bba 100644 --- a/arch/arm/configs/dove_defconfig +++ b/arch/arm/configs/dove_defconfig @@ -63,7 +63,6 @@ CONFIG_INPUT_EVDEV=y # CONFIG_MOUSE_PS2 is not set # CONFIG_SERIO is not set CONFIG_LEGACY_PTY_COUNT=16 -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_8250=y CONFIG_SERIAL_8250_CONSOLE=y CONFIG_SERIAL_8250_RUNTIME_UARTS=2 diff --git a/arch/arm/configs/magician_defconfig b/arch/arm/configs/magician_defconfig index b4670d42f378..abde1fb23b20 100644 --- a/arch/arm/configs/magician_defconfig +++ b/arch/arm/configs/magician_defconfig @@ -72,7 +72,6 @@ CONFIG_INPUT_TOUCHSCREEN=y CONFIG_INPUT_MISC=y CONFIG_INPUT_UINPUT=m # CONFIG_SERIO is not set -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_PXA=y # CONFIG_LEGACY_PTYS is not set # CONFIG_HW_RANDOM is not set diff --git a/arch/arm/configs/moxart_defconfig b/arch/arm/configs/moxart_defconfig index 6834e97af348..eacc089d86c5 100644 --- a/arch/arm/configs/moxart_defconfig +++ b/arch/arm/configs/moxart_defconfig @@ -79,7 +79,6 @@ CONFIG_INPUT_EVBUG=y # CONFIG_SERIO is not set # CONFIG_VT is not set # CONFIG_LEGACY_PTYS is not set -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_8250=y CONFIG_SERIAL_8250_CONSOLE=y CONFIG_SERIAL_8250_NR_UARTS=1 diff --git a/arch/arm/configs/mps2_defconfig b/arch/arm/configs/mps2_defconfig index 1d923dbb9928..89f4a6ff30bd 100644 --- a/arch/arm/configs/mps2_defconfig +++ b/arch/arm/configs/mps2_defconfig @@ -69,7 +69,6 @@ CONFIG_SMSC911X=y # CONFIG_VT is not set # CONFIG_LEGACY_PTYS is not set CONFIG_SERIAL_NONSTANDARD=y -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_MPS2_UART_CONSOLE=y CONFIG_SERIAL_MPS2_UART=y # CONFIG_HW_RANDOM is not set diff --git a/arch/arm/configs/mvebu_v5_defconfig b/arch/arm/configs/mvebu_v5_defconfig index 4f16716bfc32..d57ff30dabff 100644 --- a/arch/arm/configs/mvebu_v5_defconfig +++ b/arch/arm/configs/mvebu_v5_defconfig @@ -100,7 +100,6 @@ CONFIG_INPUT_EVDEV=y CONFIG_KEYBOARD_GPIO=y # CONFIG_INPUT_MOUSE is not set CONFIG_LEGACY_PTY_COUNT=16 -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_8250=y CONFIG_SERIAL_8250_CONSOLE=y CONFIG_SERIAL_8250_RUNTIME_UARTS=2 diff --git a/arch/arm/configs/xcep_defconfig b/arch/arm/configs/xcep_defconfig index f1fbdfc5c8c6..4d8e7f2eaef7 100644 --- a/arch/arm/configs/xcep_defconfig +++ b/arch/arm/configs/xcep_defconfig @@ -53,7 +53,6 @@ CONFIG_NET_ETHERNET=y # CONFIG_INPUT_KEYBOARD is not set # CONFIG_INPUT_MOUSE is not set # CONFIG_SERIO is not set -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_PXA=y CONFIG_SERIAL_PXA_CONSOLE=y # CONFIG_LEGACY_PTYS is not set diff --git a/arch/h8300/configs/edosk2674_defconfig b/arch/h8300/configs/edosk2674_defconfig index 23791dcf6c25..7137883ff4c7 100644 --- a/arch/h8300/configs/edosk2674_defconfig +++ b/arch/h8300/configs/edosk2674_defconfig @@ -32,7 +32,6 @@ CONFIG_BINFMT_FLAT=y # CONFIG_VT is not set # CONFIG_UNIX98_PTYS is not set # CONFIG_LEGACY_PTYS is not set -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_SH_SCI=y CONFIG_SERIAL_SH_SCI_CONSOLE=y # CONFIG_HW_RANDOM is not set diff --git a/arch/h8300/configs/h8300h-sim_defconfig b/arch/h8300/configs/h8300h-sim_defconfig index 7fc9c2f0acc0..d4e066a1529a 100644 --- a/arch/h8300/configs/h8300h-sim_defconfig +++ b/arch/h8300/configs/h8300h-sim_defconfig @@ -32,7 +32,6 @@ CONFIG_BINFMT_FLAT=y # CONFIG_VT is not set # CONFIG_UNIX98_PTYS is not set # CONFIG_LEGACY_PTYS is not set -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_SH_SCI=y CONFIG_SERIAL_SH_SCI_EARLYCON=y # CONFIG_HW_RANDOM is not set diff --git a/arch/h8300/configs/h8s-sim_defconfig b/arch/h8300/configs/h8s-sim_defconfig index 23791dcf6c25..7137883ff4c7 100644 --- a/arch/h8300/configs/h8s-sim_defconfig +++ b/arch/h8300/configs/h8s-sim_defconfig @@ -32,7 +32,6 @@ CONFIG_BINFMT_FLAT=y # CONFIG_VT is not set # CONFIG_UNIX98_PTYS is not set # CONFIG_LEGACY_PTYS is not set -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_SH_SCI=y CONFIG_SERIAL_SH_SCI_CONSOLE=y # CONFIG_HW_RANDOM is not set diff --git a/arch/hexagon/configs/comet_defconfig b/arch/hexagon/configs/comet_defconfig index f19ae2ab0aaa..c5a214716a38 100644 --- a/arch/hexagon/configs/comet_defconfig +++ b/arch/hexagon/configs/comet_defconfig @@ -34,7 +34,6 @@ CONFIG_NET_ETHERNET=y # CONFIG_SERIO is not set # CONFIG_CONSOLE_TRANSLATIONS is not set CONFIG_LEGACY_PTY_COUNT=64 -# CONFIG_DEVKMEM is not set # CONFIG_HW_RANDOM is not set CONFIG_SPI=y CONFIG_SPI_DEBUG=y diff --git a/arch/m68k/configs/amcore_defconfig b/arch/m68k/configs/amcore_defconfig index 3a84f24d41c8..6d9ed2198170 100644 --- a/arch/m68k/configs/amcore_defconfig +++ b/arch/m68k/configs/amcore_defconfig @@ -60,7 +60,6 @@ CONFIG_DM9000=y # CONFIG_VT is not set # CONFIG_UNIX98_PTYS is not set # CONFIG_DEVMEM is not set -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_MCF=y CONFIG_SERIAL_MCF_BAUDRATE=115200 CONFIG_SERIAL_MCF_CONSOLE=y diff --git a/arch/openrisc/configs/or1ksim_defconfig b/arch/openrisc/configs/or1ksim_defconfig index 75f2da324d0e..6e1e004047c7 100644 --- a/arch/openrisc/configs/or1ksim_defconfig +++ b/arch/openrisc/configs/or1ksim_defconfig @@ -43,7 +43,6 @@ CONFIG_MICREL_PHY=y # CONFIG_SERIO is not set # CONFIG_VT is not set # CONFIG_LEGACY_PTYS is not set -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_8250=y CONFIG_SERIAL_8250_CONSOLE=y CONFIG_SERIAL_OF_PLATFORM=y diff --git a/arch/sh/configs/edosk7705_defconfig b/arch/sh/configs/edosk7705_defconfig index ef7cc31997b1..9ee35269bee2 100644 --- a/arch/sh/configs/edosk7705_defconfig +++ b/arch/sh/configs/edosk7705_defconfig @@ -23,7 +23,6 @@ CONFIG_SH_PCLK_FREQ=31250000 # CONFIG_INPUT is not set # CONFIG_SERIO is not set # CONFIG_VT is not set -# CONFIG_DEVKMEM is not set # CONFIG_UNIX98_PTYS is not set # CONFIG_LEGACY_PTYS is not set # CONFIG_HW_RANDOM is not set diff --git a/arch/sh/configs/se7206_defconfig b/arch/sh/configs/se7206_defconfig index 315b04a8dd2f..601d062250d1 100644 --- a/arch/sh/configs/se7206_defconfig +++ b/arch/sh/configs/se7206_defconfig @@ -71,7 +71,6 @@ CONFIG_SMC91X=y # CONFIG_INPUT is not set # CONFIG_SERIO is not set # CONFIG_VT is not set -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_SH_SCI=y CONFIG_SERIAL_SH_SCI_NR_UARTS=4 CONFIG_SERIAL_SH_SCI_CONSOLE=y diff --git a/arch/sh/configs/sh2007_defconfig b/arch/sh/configs/sh2007_defconfig index 99975db461d8..79f02f1c0dc8 100644 --- a/arch/sh/configs/sh2007_defconfig +++ b/arch/sh/configs/sh2007_defconfig @@ -75,7 +75,6 @@ CONFIG_INPUT_FF_MEMLESS=y # CONFIG_INPUT_MOUSE is not set # CONFIG_SERIO is not set CONFIG_VT_HW_CONSOLE_BINDING=y -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_SH_SCI=y CONFIG_SERIAL_SH_SCI_CONSOLE=y # CONFIG_LEGACY_PTYS is not set diff --git a/arch/sh/configs/sh7724_generic_defconfig b/arch/sh/configs/sh7724_generic_defconfig index 2c46c0004780..cbc9389a89a8 100644 --- a/arch/sh/configs/sh7724_generic_defconfig +++ b/arch/sh/configs/sh7724_generic_defconfig @@ -18,7 +18,6 @@ CONFIG_CPU_IDLE=y # CONFIG_INPUT is not set # CONFIG_SERIO is not set # CONFIG_VT is not set -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_SH_SCI=y CONFIG_SERIAL_SH_SCI_NR_UARTS=6 CONFIG_SERIAL_SH_SCI_CONSOLE=y diff --git a/arch/sh/configs/sh7770_generic_defconfig b/arch/sh/configs/sh7770_generic_defconfig index 88193153e51b..ee2357deba0f 100644 --- a/arch/sh/configs/sh7770_generic_defconfig +++ b/arch/sh/configs/sh7770_generic_defconfig @@ -20,7 +20,6 @@ CONFIG_CPU_IDLE=y # CONFIG_INPUT is not set # CONFIG_SERIO is not set # CONFIG_VT is not set -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_SH_SCI=y CONFIG_SERIAL_SH_SCI_NR_UARTS=6 CONFIG_SERIAL_SH_SCI_CONSOLE=y diff --git a/arch/sh/configs/sh7785lcr_32bit_defconfig b/arch/sh/configs/sh7785lcr_32bit_defconfig index 9b885c14c400..5c725c75fcef 100644 --- a/arch/sh/configs/sh7785lcr_32bit_defconfig +++ b/arch/sh/configs/sh7785lcr_32bit_defconfig @@ -66,7 +66,6 @@ CONFIG_INPUT_FF_MEMLESS=m CONFIG_INPUT_EVDEV=y CONFIG_INPUT_EVBUG=m CONFIG_VT_HW_CONSOLE_BINDING=y -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_SH_SCI=y CONFIG_SERIAL_SH_SCI_NR_UARTS=6 CONFIG_SERIAL_SH_SCI_CONSOLE=y diff --git a/arch/sparc/configs/sparc64_defconfig b/arch/sparc/configs/sparc64_defconfig index 12a4fb0bd52a..18099099583e 100644 --- a/arch/sparc/configs/sparc64_defconfig +++ b/arch/sparc/configs/sparc64_defconfig @@ -122,7 +122,6 @@ CONFIG_INPUT_SPARCSPKR=y # CONFIG_SERIO_SERPORT is not set CONFIG_SERIO_PCIPS2=m CONFIG_SERIO_RAW=m -# CONFIG_DEVKMEM is not set CONFIG_SERIAL_SUNSU=y CONFIG_SERIAL_SUNSU_CONSOLE=y CONFIG_SERIAL_SUNSAB=y diff --git a/arch/xtensa/configs/xip_kc705_defconfig b/arch/xtensa/configs/xip_kc705_defconfig index 4f1ff9531f6a..062148e17135 100644 --- a/arch/xtensa/configs/xip_kc705_defconfig +++ b/arch/xtensa/configs/xip_kc705_defconfig @@ -72,7 +72,6 @@ CONFIG_MARVELL_PHY=y # CONFIG_INPUT_KEYBOARD is not set # CONFIG_INPUT_MOUSE is not set # CONFIG_SERIO is not set -CONFIG_DEVKMEM=y CONFIG_SERIAL_8250=y # CONFIG_SERIAL_8250_DEPRECATED_OPTIONS is not set CONFIG_SERIAL_8250_CONSOLE=y diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig index d229a2d0c017..b151e0fcdeb5 100644 --- a/drivers/char/Kconfig +++ b/drivers/char/Kconfig @@ -334,16 +334,6 @@ config DEVMEM memory. When in doubt, say "Y". -config DEVKMEM - bool "/dev/kmem virtual device support" - # On arm64, VMALLOC_START < PAGE_OFFSET, which confuses kmem read/write - depends on !ARM64 - help - Say Y here if you want to support the /dev/kmem device. The - /dev/kmem device is rarely used, but can be used for certain - kind of kernel debugging operations. - When in doubt, say "N". - config NVRAM tristate "/dev/nvram support" depends on X86 || HAVE_ARCH_NVRAM_OPS diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 869b9f5e8e03..15dc54fa1d47 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -403,221 +403,6 @@ static int mmap_mem(struct file *file, struct vm_area_struct *vma) return 0; } -static int mmap_kmem(struct file *file, struct vm_area_struct *vma) -{ - unsigned long pfn; - - /* Turn a kernel-virtual address into a physical page frame */ - pfn = __pa((u64)vma->vm_pgoff << PAGE_SHIFT) >> PAGE_SHIFT; - - /* - * RED-PEN: on some architectures there is more mapped memory than - * available in mem_map which pfn_valid checks for. Perhaps should add a - * new macro here. - * - * RED-PEN: vmalloc is not supported right now. - */ - if (!pfn_valid(pfn)) - return -EIO; - - vma->vm_pgoff = pfn; - return mmap_mem(file, vma); -} - -/* - * This function reads the *virtual* memory as seen by the kernel. - */ -static ssize_t read_kmem(struct file *file, char __user *buf, - size_t count, loff_t *ppos) -{ - unsigned long p = *ppos; - ssize_t low_count, read, sz; - char *kbuf; /* k-addr because vread() takes vmlist_lock rwlock */ - int err = 0; - - read = 0; - if (p < (unsigned long) high_memory) { - low_count = count; - if (count > (unsigned long)high_memory - p) - low_count = (unsigned long)high_memory - p; - -#ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED - /* we don't have page 0 mapped on sparc and m68k.. */ - if (p < PAGE_SIZE && low_count > 0) { - sz = size_inside_page(p, low_count); - if (clear_user(buf, sz)) - return -EFAULT; - buf += sz; - p += sz; - read += sz; - low_count -= sz; - count -= sz; - } -#endif - while (low_count > 0) { - sz = size_inside_page(p, low_count); - - /* - * On ia64 if a page has been mapped somewhere as - * uncached, then it must also be accessed uncached - * by the kernel or data corruption may occur - */ - kbuf = xlate_dev_kmem_ptr((void *)p); - if (!virt_addr_valid(kbuf)) - return -ENXIO; - - if (copy_to_user(buf, kbuf, sz)) - return -EFAULT; - buf += sz; - p += sz; - read += sz; - low_count -= sz; - count -= sz; - if (should_stop_iteration()) { - count = 0; - break; - } - } - } - - if (count > 0) { - kbuf = (char *)__get_free_page(GFP_KERNEL); - if (!kbuf) - return -ENOMEM; - while (count > 0) { - sz = size_inside_page(p, count); - if (!is_vmalloc_or_module_addr((void *)p)) { - err = -ENXIO; - break; - } - sz = vread(kbuf, (char *)p, sz); - if (!sz) - break; - if (copy_to_user(buf, kbuf, sz)) { - err = -EFAULT; - break; - } - count -= sz; - buf += sz; - read += sz; - p += sz; - if (should_stop_iteration()) - break; - } - free_page((unsigned long)kbuf); - } - *ppos = p; - return read ? read : err; -} - - -static ssize_t do_write_kmem(unsigned long p, const char __user *buf, - size_t count, loff_t *ppos) -{ - ssize_t written, sz; - unsigned long copied; - - written = 0; -#ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED - /* we don't have page 0 mapped on sparc and m68k.. */ - if (p < PAGE_SIZE) { - sz = size_inside_page(p, count); - /* Hmm. Do something? */ - buf += sz; - p += sz; - count -= sz; - written += sz; - } -#endif - - while (count > 0) { - void *ptr; - - sz = size_inside_page(p, count); - - /* - * On ia64 if a page has been mapped somewhere as uncached, then - * it must also be accessed uncached by the kernel or data - * corruption may occur. - */ - ptr = xlate_dev_kmem_ptr((void *)p); - if (!virt_addr_valid(ptr)) - return -ENXIO; - - copied = copy_from_user(ptr, buf, sz); - if (copied) { - written += sz - copied; - if (written) - break; - return -EFAULT; - } - buf += sz; - p += sz; - count -= sz; - written += sz; - if (should_stop_iteration()) - break; - } - - *ppos += written; - return written; -} - -/* - * This function writes to the *virtual* memory as seen by the kernel. - */ -static ssize_t write_kmem(struct file *file, const char __user *buf, - size_t count, loff_t *ppos) -{ - unsigned long p = *ppos; - ssize_t wrote = 0; - ssize_t virtr = 0; - char *kbuf; /* k-addr because vwrite() takes vmlist_lock rwlock */ - int err = 0; - - if (p < (unsigned long) high_memory) { - unsigned long to_write = min_t(unsigned long, count, - (unsigned long)high_memory - p); - wrote = do_write_kmem(p, buf, to_write, ppos); - if (wrote != to_write) - return wrote; - p += wrote; - buf += wrote; - count -= wrote; - } - - if (count > 0) { - kbuf = (char *)__get_free_page(GFP_KERNEL); - if (!kbuf) - return wrote ? wrote : -ENOMEM; - while (count > 0) { - unsigned long sz = size_inside_page(p, count); - unsigned long n; - - if (!is_vmalloc_or_module_addr((void *)p)) { - err = -ENXIO; - break; - } - n = copy_from_user(kbuf, buf, sz); - if (n) { - err = -EFAULT; - break; - } - vwrite(kbuf, (char *)p, sz); - count -= sz; - buf += sz; - virtr += sz; - p += sz; - if (should_stop_iteration()) - break; - } - free_page((unsigned long)kbuf); - } - - *ppos = p; - return virtr + wrote ? : err; -} - static ssize_t read_port(struct file *file, char __user *buf, size_t count, loff_t *ppos) { @@ -855,7 +640,6 @@ static int open_port(struct inode *inode, struct file *filp) #define write_zero write_null #define write_iter_zero write_iter_null #define open_mem open_port -#define open_kmem open_mem static const struct file_operations __maybe_unused mem_fops = { .llseek = memory_lseek, @@ -869,18 +653,6 @@ static const struct file_operations __maybe_unused mem_fops = { #endif }; -static const struct file_operations __maybe_unused kmem_fops = { - .llseek = memory_lseek, - .read = read_kmem, - .write = write_kmem, - .mmap = mmap_kmem, - .open = open_kmem, -#ifndef CONFIG_MMU - .get_unmapped_area = get_unmapped_area_mem, - .mmap_capabilities = memory_mmap_capabilities, -#endif -}; - static const struct file_operations null_fops = { .llseek = null_lseek, .read = read_null, @@ -924,9 +696,6 @@ static const struct memdev { } devlist[] = { #ifdef CONFIG_DEVMEM [DEVMEM_MINOR] = { "mem", 0, &mem_fops, FMODE_UNSIGNED_OFFSET }, -#endif -#ifdef CONFIG_DEVKMEM - [2] = { "kmem", 0, &kmem_fops, FMODE_UNSIGNED_OFFSET }, #endif [3] = { "null", 0666, &null_fops, 0 }, #ifdef CONFIG_DEVPORT diff --git a/include/linux/fs.h b/include/linux/fs.h index ec8f3ddf4a6a..a727186ef4cd 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -144,7 +144,7 @@ typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset, /* Expect random access pattern */ #define FMODE_RANDOM ((__force fmode_t)0x1000) -/* File is huge (eg. /dev/kmem): treat loff_t as unsigned */ +/* File is huge (eg. /dev/mem): treat loff_t as unsigned */ #define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000) /* File is opened with O_PATH; almost nothing can be done with it */ diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h index df92211cf771..390af680e916 100644 --- a/include/linux/vmalloc.h +++ b/include/linux/vmalloc.h @@ -198,7 +198,7 @@ static inline void set_vm_flush_reset_perms(void *addr) } #endif -/* for /dev/kmem */ +/* for /proc/kcore */ extern long vread(char *buf, char *addr, unsigned long count); extern long vwrite(char *buf, char *addr, unsigned long count); diff --git a/kernel/configs/android-base.config b/kernel/configs/android-base.config index d3fd428f4b92..eb701b2ac72f 100644 --- a/kernel/configs/android-base.config +++ b/kernel/configs/android-base.config @@ -1,5 +1,4 @@ # KEEP ALPHABETICALLY SORTED -# CONFIG_DEVKMEM is not set # CONFIG_DEVMEM is not set # CONFIG_FHANDLE is not set # CONFIG_INET_LRO is not set diff --git a/mm/ksm.c b/mm/ksm.c index 9694ee2c71de..901cab89299d 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -461,7 +461,7 @@ static inline bool ksm_test_exit(struct mm_struct *mm) * but taking great care only to touch a ksm page, in a VM_MERGEABLE vma, * in case the application has unmapped and remapped mm,addr meanwhile. * Could a ksm page appear anywhere else? Actually yes, in a VM_PFNMAP - * mmap of /dev/mem or /dev/kmem, where we would not want to touch it. + * mmap of /dev/mem, where we would not want to touch it. * * FAULT_FLAG/FOLL_REMOTE are because we do this outside the context * of the process that owns 'vma'. We also do not want to enforce diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 4f5f8c907897..ccb405b82581 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -2875,7 +2875,7 @@ static int aligned_vwrite(char *buf, char *addr, unsigned long count) * Note: In usual ops, vread() is never necessary because the caller * should know vmalloc() area is valid and can use memcpy(). * This is for routines which have to access vmalloc area without - * any information, as /dev/kmem. + * any information, as /proc/kcore. * * Return: number of bytes for which addr and buf should be increased * (same number as @count) or %0 if [addr...addr+count) doesn't From patchwork Fri Mar 19 14:34:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 12151157 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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 4DF37C433DB for ; Fri, 19 Mar 2021 14:36:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DA1AD64F18 for ; Fri, 19 Mar 2021 14:36:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DA1AD64F18 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 72D756B0072; Fri, 19 Mar 2021 10:36:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6DC236B0074; Fri, 19 Mar 2021 10:36:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4E20C6B0075; Fri, 19 Mar 2021 10:36:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0190.hostedemail.com [216.40.44.190]) by kanga.kvack.org (Postfix) with ESMTP id 313C96B0072 for ; Fri, 19 Mar 2021 10:36:24 -0400 (EDT) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id E4D386C26 for ; Fri, 19 Mar 2021 14:36:23 +0000 (UTC) X-FDA: 77936874246.18.F03906A Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf28.hostedemail.com (Postfix) with ESMTP id B7F8020003B3 for ; Fri, 19 Mar 2021 14:36:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1616164578; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=FXYl9hPij054vFEEXKLgQXfdpg6LLSdzf8h+kRhT++U=; b=h5ZM9BOaHWki/RayXw430fq54ViKVrZ8CkgANtwQoh20Jr1aY8rZvbN5IFi4feJiJFmA69 +Gj0kT2zOlM7KtIezaNjdPTkWJLaExd9Af+z0QXOq3tZtZ3DppioLYt2ZlCIwBO6AxK9Oq dGbTgeD39dcCIUbkPiGVu/G0SRwt5r8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-142-5pJmeDzBN1Gy0hLj-NyWUw-1; Fri, 19 Mar 2021 10:36:12 -0400 X-MC-Unique: 5pJmeDzBN1Gy0hLj-NyWUw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C0C0A84BA42; Fri, 19 Mar 2021 14:36:06 +0000 (UTC) Received: from t480s.redhat.com (ovpn-112-11.ams2.redhat.com [10.36.112.11]) by smtp.corp.redhat.com (Postfix) with ESMTP id B096F610F5; Fri, 19 Mar 2021 14:35:46 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, David Hildenbrand , Richard Henderson , Ivan Kokshaysky , Matt Turner , Russell King , Brian Cain , Geert Uytterhoeven , Thomas Bogendoerfer , "James E.J. Bottomley" , Helge Deller , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Yoshinori Sato , Rich Felker , "David S. Miller" , Arnd Bergmann , Andrew Morton , Krzysztof Kozlowski , Mikulas Patocka , Luc Van Oostenryck , Mike Rapoport , Palmer Dabbelt , Luis Chamberlain , Greentime Hu , Sebastian Andrzej Siewior , Randy Dunlap , Jiaxun Yang , "Peter Zijlstra (Intel)" , Christophe Leroy , Gerald Schaefer , Niklas Schnelle , Pierre Morel , Ingo Molnar , Kuninori Morimoto , linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-hexagon@vger.kernel.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-arch@vger.kernel.org Subject: [PATCH RFC 2/3] mm: remove xlate_dev_kmem_ptr() Date: Fri, 19 Mar 2021 15:34:51 +0100 Message-Id: <20210319143452.25948-3-david@redhat.com> In-Reply-To: <20210319143452.25948-1-david@redhat.com> References: <20210319143452.25948-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Stat-Signature: f1mx7gb4xjq189qzw8kf5s7nribi4dog X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: B7F8020003B3 Received-SPF: none (redhat.com>: No applicable sender policy available) receiver=imf28; identity=mailfrom; envelope-from=""; helo=us-smtp-delivery-124.mimecast.com; client-ip=170.10.133.124 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616164578-164789 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Since /dev/kmem has been removed, let's remove the xlate_dev_kmem_ptr() leftovers. Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Russell King Cc: Brian Cain Cc: Geert Uytterhoeven Cc: Thomas Bogendoerfer Cc: "James E.J. Bottomley" Cc: Helge Deller Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: Yoshinori Sato Cc: Rich Felker Cc: "David S. Miller" Cc: Arnd Bergmann Cc: Andrew Morton Cc: David Hildenbrand Cc: Krzysztof Kozlowski Cc: Mikulas Patocka Cc: Luc Van Oostenryck Cc: Mike Rapoport Cc: Palmer Dabbelt Cc: Luis Chamberlain Cc: Greentime Hu Cc: Sebastian Andrzej Siewior Cc: Randy Dunlap Cc: Jiaxun Yang Cc: "Peter Zijlstra (Intel)" Cc: Christophe Leroy Cc: Gerald Schaefer Cc: Niklas Schnelle Cc: Pierre Morel Cc: Ingo Molnar Cc: Kuninori Morimoto Cc: linux-alpha@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-hexagon@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-m68k@lists.linux-m68k.org Cc: linux-mips@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-arch@vger.kernel.org Signed-off-by: David Hildenbrand Acked-by: Geert Uytterhoeven --- arch/alpha/include/asm/io.h | 5 ----- arch/arm/include/asm/io.h | 5 ----- arch/hexagon/include/asm/io.h | 1 - arch/ia64/include/asm/io.h | 1 - arch/ia64/include/asm/uaccess.h | 18 ------------------ arch/m68k/include/asm/io_mm.h | 5 ----- arch/mips/include/asm/io.h | 5 ----- arch/parisc/include/asm/io.h | 5 ----- arch/powerpc/include/asm/io.h | 5 ----- arch/s390/include/asm/io.h | 5 ----- arch/sh/include/asm/io.h | 5 ----- arch/sparc/include/asm/io_64.h | 5 ----- include/asm-generic/io.h | 11 ----------- 13 files changed, 76 deletions(-) diff --git a/arch/alpha/include/asm/io.h b/arch/alpha/include/asm/io.h index 1f6a909d1fa5..0fab5ac90775 100644 --- a/arch/alpha/include/asm/io.h +++ b/arch/alpha/include/asm/io.h @@ -602,11 +602,6 @@ extern void outsl (unsigned long port, const void *src, unsigned long count); */ #define xlate_dev_mem_ptr(p) __va(p) -/* - * Convert a virtual cached pointer to an uncached pointer - */ -#define xlate_dev_kmem_ptr(p) p - #endif /* __KERNEL__ */ #endif /* __ALPHA_IO_H */ diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h index fc748122f1e0..f74944c6fe8d 100644 --- a/arch/arm/include/asm/io.h +++ b/arch/arm/include/asm/io.h @@ -430,11 +430,6 @@ extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr); */ #define xlate_dev_mem_ptr(p) __va(p) -/* - * Convert a virtual cached pointer to an uncached pointer - */ -#define xlate_dev_kmem_ptr(p) p - #include #ifdef CONFIG_MMU diff --git a/arch/hexagon/include/asm/io.h b/arch/hexagon/include/asm/io.h index bda2a9c2df78..c33241425a5c 100644 --- a/arch/hexagon/include/asm/io.h +++ b/arch/hexagon/include/asm/io.h @@ -64,7 +64,6 @@ static inline void *phys_to_virt(unsigned long address) * convert a physical pointer to a virtual kernel pointer for * /dev/mem access. */ -#define xlate_dev_kmem_ptr(p) __va(p) #define xlate_dev_mem_ptr(p) __va(p) /* diff --git a/arch/ia64/include/asm/io.h b/arch/ia64/include/asm/io.h index 3d666a11a2de..6d93b923b379 100644 --- a/arch/ia64/include/asm/io.h +++ b/arch/ia64/include/asm/io.h @@ -277,7 +277,6 @@ extern void memset_io(volatile void __iomem *s, int c, long n); #define memcpy_fromio memcpy_fromio #define memcpy_toio memcpy_toio #define memset_io memset_io -#define xlate_dev_kmem_ptr xlate_dev_kmem_ptr #define xlate_dev_mem_ptr xlate_dev_mem_ptr #include #undef PCI_IOBASE diff --git a/arch/ia64/include/asm/uaccess.h b/arch/ia64/include/asm/uaccess.h index 179243c3dfc7..e19d2dcc0ced 100644 --- a/arch/ia64/include/asm/uaccess.h +++ b/arch/ia64/include/asm/uaccess.h @@ -272,22 +272,4 @@ xlate_dev_mem_ptr(phys_addr_t p) return ptr; } -/* - * Convert a virtual cached kernel memory pointer to an uncached pointer - */ -static __inline__ void * -xlate_dev_kmem_ptr(void *p) -{ - struct page *page; - void *ptr; - - page = virt_to_page((unsigned long)p); - if (PageUncached(page)) - ptr = (void *)__pa(p) + __IA64_UNCACHED_OFFSET; - else - ptr = p; - - return ptr; -} - #endif /* _ASM_IA64_UACCESS_H */ diff --git a/arch/m68k/include/asm/io_mm.h b/arch/m68k/include/asm/io_mm.h index 819f611dccf2..d41fa488453b 100644 --- a/arch/m68k/include/asm/io_mm.h +++ b/arch/m68k/include/asm/io_mm.h @@ -397,11 +397,6 @@ static inline void isa_delay(void) */ #define xlate_dev_mem_ptr(p) __va(p) -/* - * Convert a virtual cached pointer to an uncached pointer - */ -#define xlate_dev_kmem_ptr(p) p - #define readb_relaxed(addr) readb(addr) #define readw_relaxed(addr) readw(addr) #define readl_relaxed(addr) readl(addr) diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h index 78537aa23500..e6373e7ac892 100644 --- a/arch/mips/include/asm/io.h +++ b/arch/mips/include/asm/io.h @@ -552,11 +552,6 @@ extern void (*_dma_cache_inv)(unsigned long start, unsigned long size); */ #define xlate_dev_mem_ptr(p) __va(p) -/* - * Convert a virtual cached pointer to an uncached pointer - */ -#define xlate_dev_kmem_ptr(p) p - void __ioread64_copy(void *to, const void __iomem *from, size_t count); #endif /* _ASM_IO_H */ diff --git a/arch/parisc/include/asm/io.h b/arch/parisc/include/asm/io.h index 8a11b8cf4719..0b5259102319 100644 --- a/arch/parisc/include/asm/io.h +++ b/arch/parisc/include/asm/io.h @@ -316,11 +316,6 @@ extern void iowrite64be(u64 val, void __iomem *addr); */ #define xlate_dev_mem_ptr(p) __va(p) -/* - * Convert a virtual cached pointer to an uncached pointer - */ -#define xlate_dev_kmem_ptr(p) p - extern int devmem_is_allowed(unsigned long pfn); #endif diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h index 273edd208ec5..f130783c8301 100644 --- a/arch/powerpc/include/asm/io.h +++ b/arch/powerpc/include/asm/io.h @@ -662,11 +662,6 @@ static inline void name at \ */ #define xlate_dev_mem_ptr(p) __va(p) -/* - * Convert a virtual cached pointer to an uncached pointer - */ -#define xlate_dev_kmem_ptr(p) p - /* * We don't do relaxed operations yet, at least not with this semantic */ diff --git a/arch/s390/include/asm/io.h b/arch/s390/include/asm/io.h index 28664ee0abc1..e3882b012bfa 100644 --- a/arch/s390/include/asm/io.h +++ b/arch/s390/include/asm/io.h @@ -20,11 +20,6 @@ void *xlate_dev_mem_ptr(phys_addr_t phys); #define unxlate_dev_mem_ptr unxlate_dev_mem_ptr void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr); -/* - * Convert a virtual cached pointer to an uncached pointer - */ -#define xlate_dev_kmem_ptr(p) p - #define IO_SPACE_LIMIT 0 void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot); diff --git a/arch/sh/include/asm/io.h b/arch/sh/include/asm/io.h index 6d5c6463bc07..cf9a3ec32406 100644 --- a/arch/sh/include/asm/io.h +++ b/arch/sh/include/asm/io.h @@ -283,11 +283,6 @@ static inline void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size, */ #define xlate_dev_mem_ptr(p) __va(p) -/* - * Convert a virtual cached pointer to an uncached pointer - */ -#define xlate_dev_kmem_ptr(p) p - #define ARCH_HAS_VALID_PHYS_ADDR_RANGE int valid_phys_addr_range(phys_addr_t addr, size_t size); int valid_mmap_phys_addr_range(unsigned long pfn, size_t size); diff --git a/arch/sparc/include/asm/io_64.h b/arch/sparc/include/asm/io_64.h index 9bb27e5c22f1..ff6fe387d78c 100644 --- a/arch/sparc/include/asm/io_64.h +++ b/arch/sparc/include/asm/io_64.h @@ -450,11 +450,6 @@ void sbus_set_sbus64(struct device *, int); */ #define xlate_dev_mem_ptr(p) __va(p) -/* - * Convert a virtual cached pointer to an uncached pointer - */ -#define xlate_dev_kmem_ptr(p) p - #endif #endif /* !(__SPARC64_IO_H) */ diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h index c6af40ce03be..33d4746b086f 100644 --- a/include/asm-generic/io.h +++ b/include/asm-generic/io.h @@ -1045,17 +1045,6 @@ static inline void pci_iounmap(struct pci_dev *dev, void __iomem *p) #endif #endif /* CONFIG_GENERIC_IOMAP */ -/* - * Convert a virtual cached pointer to an uncached pointer - */ -#ifndef xlate_dev_kmem_ptr -#define xlate_dev_kmem_ptr xlate_dev_kmem_ptr -static inline void *xlate_dev_kmem_ptr(void *addr) -{ - return addr; -} -#endif - #ifndef xlate_dev_mem_ptr #define xlate_dev_mem_ptr xlate_dev_mem_ptr static inline void *xlate_dev_mem_ptr(phys_addr_t addr) From patchwork Fri Mar 19 14:34:52 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 12151159 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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 51B5CC433E9 for ; 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client-ip=216.205.24.124 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616164578-103041 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: The last user (/dev/kmem) is gone. Let's drop it. Cc: Andrew Morton Cc: Hillf Danton Cc: Michal Hocko Cc: Matthew Wilcox Cc: Oleksiy Avramchenko Cc: Steven Rostedt Cc: Minchan Kim Cc: huang ying Signed-off-by: David Hildenbrand Acked-by: Michal Hocko --- include/linux/vmalloc.h | 1 - mm/vmalloc.c | 111 ---------------------------------------- 2 files changed, 112 deletions(-) diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h index 390af680e916..9c1b17c7dd95 100644 --- a/include/linux/vmalloc.h +++ b/include/linux/vmalloc.h @@ -200,7 +200,6 @@ static inline void set_vm_flush_reset_perms(void *addr) /* for /proc/kcore */ extern long vread(char *buf, char *addr, unsigned long count); -extern long vwrite(char *buf, char *addr, unsigned long count); /* * Internals. Dont't use.. diff --git a/mm/vmalloc.c b/mm/vmalloc.c index ccb405b82581..07a39881f9d6 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -2820,43 +2820,6 @@ static int aligned_vread(char *buf, char *addr, unsigned long count) return copied; } -static int aligned_vwrite(char *buf, char *addr, unsigned long count) -{ - struct page *p; - int copied = 0; - - while (count) { - unsigned long offset, length; - - offset = offset_in_page(addr); - length = PAGE_SIZE - offset; - if (length > count) - length = count; - p = vmalloc_to_page(addr); - /* - * To do safe access to this _mapped_ area, we need - * lock. But adding lock here means that we need to add - * overhead of vmalloc()/vfree() calles for this _debug_ - * interface, rarely used. Instead of that, we'll use - * kmap() and get small overhead in this access function. - */ - if (p) { - /* - * we can expect USER0 is not used (see vread/vwrite's - * function description) - */ - void *map = kmap_atomic(p); - memcpy(map + offset, buf, length); - kunmap_atomic(map); - } - addr += length; - buf += length; - copied += length; - count -= length; - } - return copied; -} - /** * vread() - read vmalloc area in a safe way. * @buf: buffer for reading data @@ -2936,80 +2899,6 @@ long vread(char *buf, char *addr, unsigned long count) return buflen; } -/** - * vwrite() - write vmalloc area in a safe way. - * @buf: buffer for source data - * @addr: vm address. - * @count: number of bytes to be read. - * - * This function checks that addr is a valid vmalloc'ed area, and - * copy data from a buffer to the given addr. If specified range of - * [addr...addr+count) includes some valid address, data is copied from - * proper area of @buf. If there are memory holes, no copy to hole. - * IOREMAP area is treated as memory hole and no copy is done. - * - * If [addr...addr+count) doesn't includes any intersects with alive - * vm_struct area, returns 0. @buf should be kernel's buffer. - * - * Note: In usual ops, vwrite() is never necessary because the caller - * should know vmalloc() area is valid and can use memcpy(). - * This is for routines which have to access vmalloc area without - * any information, as /dev/kmem. - * - * Return: number of bytes for which addr and buf should be - * increased (same number as @count) or %0 if [addr...addr+count) - * doesn't include any intersection with valid vmalloc area - */ -long vwrite(char *buf, char *addr, unsigned long count) -{ - struct vmap_area *va; - struct vm_struct *vm; - char *vaddr; - unsigned long n, buflen; - int copied = 0; - - /* Don't allow overflow */ - if ((unsigned long) addr + count < count) - count = -(unsigned long) addr; - buflen = count; - - spin_lock(&vmap_area_lock); - list_for_each_entry(va, &vmap_area_list, list) { - if (!count) - break; - - if (!va->vm) - continue; - - vm = va->vm; - vaddr = (char *) vm->addr; - if (addr >= vaddr + get_vm_area_size(vm)) - continue; - while (addr < vaddr) { - if (count == 0) - goto finished; - buf++; - addr++; - count--; - } - n = vaddr + get_vm_area_size(vm) - addr; - if (n > count) - n = count; - if (!(vm->flags & VM_IOREMAP)) { - aligned_vwrite(buf, addr, n); - copied++; - } - buf += n; - addr += n; - count -= n; - } -finished: - spin_unlock(&vmap_area_lock); - if (!copied) - return 0; - return buflen; -} - /** * remap_vmalloc_range_partial - map vmalloc pages to userspace * @vma: vma to cover