From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754228AbbANRhM (ORCPT ); Wed, 14 Jan 2015 12:37:12 -0500 Received: from mx1.redhat.com ([209.132.183.28]:35608 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751959AbbANRhJ (ORCPT ); Wed, 14 Jan 2015 12:37:09 -0500 Date: Wed, 14 Jan 2015 19:36:18 +0200 From: "Michael S. Tsirkin" To: Arnd Bergmann Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, davem@davemloft.net, deller@gmx.de, egtvedt@samfundet.no, geert@linux-m68k.org, james.hogan@imgtec.com, jcmvbkbc@gmail.com, mst@redhat.com, realmz6@gmail.com, sam@ravnborg.org, tglx@linutronix.de, will.deacon@arm.com Subject: [PULL] uaccess: fix sparse warning on get/put_user for bitwise types Message-ID: <20150114173618.GA12436@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Mutt-Fcc: =sent Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Arnd, As you asked, here's a pull request. This has been in linux-next apparently with no ill effects. The following changes since commit 99975cc6ada0d5f2675e83abecae05aba5f437d2: vhost/net: length miscalculation (2015-01-07 12:22:00 +0200) are available in the git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git tags/uaccess_for_upstream for you to fetch changes up to 0795cb1b46e7938ed679ccd48f933e75272b30e3: sparc32: nocheck uaccess coding style tweaks (2015-01-13 15:24:14 +0200) ---------------------------------------------------------------- uaccess: fix sparse warning on get/put_user for bitwise types At the moment, if p and x are both tagged as bitwise types, some of get_user(x, p), put_user(x, p), __get_user(x, p), __put_user(x, p) might produce a sparse warning on many architectures. This is a false positive: *p on these architectures is loaded into long (typically using asm), then cast back to typeof(*p). When typeof(*p) is a bitwise type (which is uncommon), such a cast needs __force, otherwise sparse produces a warning. Some architectures already have the __force tag, add it where it's missing. I verified that adding these __force casts does not supress any useful warnings. Specifically, vhost wants to read/write bitwise types in userspace memory using get_user/put_user. At the moment this triggers sparse errors, since the value is passed through an integer. For example: __le32 __user *p; __u32 x; both put_user(x, p); and get_user(x, p); should be safe, but produce warnings on some architectures. While there, I noticed that a bunch of architectures violated coding style rules within uaccess macros. Included patches to fix them up. Signed-off-by: Michael S. Tsirkin ---------------------------------------------------------------- Michael S. Tsirkin (37): x86/uaccess: fix sparse errors alpha/uaccess: fix sparse errors arm64/uaccess: fix sparse errors avr32/uaccess: fix sparse errors blackfin/uaccess: fix sparse errors cris/uaccess: fix sparse errors ia64/uaccess: fix sparse errors m32r/uaccess: fix sparse errors metag/uaccess: fix sparse errors openrisc/uaccess: fix sparse errors parisc/uaccess: fix sparse errors sh/uaccess: fix sparse errors sparc32/uaccess: fix sparse errors sparc64/uaccess: fix sparse errors m68k/uaccess: fix sparse errors arm: fix put_user sparse errors blackfin: fix put_user sparse errors ia64: fix put_user sparse errors metag: fix put_user sparse errors sh: fix put_user sparse errors avr32: whitespace fix sparc32: uaccess_32 macro whitespace fixes sparc64: uaccess_64 macro whitespace fixes blackfin: macro whitespace fixes alpha: macro whitespace fixes arm: macro whitespace fixes arm64: macro whitespace fixes avr32: macro whitespace fixes cris: macro whitespace fixes frv: macro whitespace fixes m32r: macro whitespace fixes m68k: macro whitespace fixes parisc: macro whitespace fixes sh: macro whitespace fixes xtensa: macro whitespace fixes sparc64: nocheck uaccess coding style tweaks sparc32: nocheck uaccess coding style tweaks arch/alpha/include/asm/uaccess.h | 86 ++++----- arch/arm/include/asm/uaccess.h | 96 +++++----- arch/arm64/include/asm/uaccess.h | 4 +- arch/avr32/include/asm/uaccess.h | 24 +-- arch/blackfin/include/asm/uaccess.h | 32 ++-- arch/cris/include/asm/uaccess.h | 117 +++++++------ arch/frv/include/asm/segment.h | 2 +- arch/ia64/include/asm/uaccess.h | 11 +- arch/m32r/include/asm/uaccess.h | 88 +++++----- arch/m68k/include/asm/segment.h | 2 +- arch/m68k/include/asm/uaccess_mm.h | 40 ++--- arch/metag/include/asm/uaccess.h | 25 +-- arch/openrisc/include/asm/uaccess.h | 4 +- arch/parisc/include/asm/uaccess.h | 116 ++++++------ arch/sh/include/asm/segment.h | 2 +- arch/sh/include/asm/uaccess.h | 4 +- arch/sh/include/asm/uaccess_64.h | 8 +- arch/sparc/include/asm/uaccess_32.h | 339 +++++++++++++++++++++--------------- arch/sparc/include/asm/uaccess_64.h | 222 ++++++++++++----------- arch/x86/include/asm/uaccess.h | 2 +- arch/xtensa/include/asm/uaccess.h | 90 +++++----- 21 files changed, 700 insertions(+), 614 deletions(-)