From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELsZTHuNdmPt2pulhoJzG7syCr4V/bWnjPUTAWBKMHWv99Wmd3owXt+eWjKtARZngQmZN4Lt ARC-Seal: i=1; a=rsa-sha256; t=1521023765; cv=none; d=google.com; s=arc-20160816; b=b+bMGlGnMKM+7qvIbrJNwmEwi6CtBbR2HbMoXtDN/RKX+2mZ253Xfbs6TxDcF7yLxe BbvSl9f3d1W+g3c9V/DYOMKdZEjIZVW33Z0BaZzNh+2LpmelewP8B599Fr3w7lj/1smy aUC3pUyfjOpWNTELEkoo4jud2cpdtBvQ45Njq835tvn3pxYj+pKNo+eK+wmZtP2lG+g2 K9oiz8dF+efur2CckfX8UzLviMraQd2PUktGMLz4OLAwtFYaLxfLNBNHVGoBId4egsjt Gotd/ssA5Z+M6O/Xw4/1sFxb0E/8EaSGi4mxILEXWYfYm8y2DW7UmjF8TvQki+b6hB/j A63A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:in-reply-to:content-disposition:mime-version:references :message-id:subject:cc:to:from:date:dkim-signature :arc-authentication-results; bh=1+bD0hmtzlCQGKdeMmJTJ571KhgL2Xq+8fpVFAxUgII=; b=eLyjRe1mk6QTg8BdLTlUB68wVbipoRFOknPBY1sX6iy2oFIsp+fUu0rF8Mk5mDWmzW BJ73NlFQtdoRsI2ICI8LeFZxMJpxbthViYDZRUIoCk1zA3CiiXqMr8afPDIXjpMDV799 YibmTnZtWFlEz+h91pao/MwLVmzKrFzibzztv1BVaeK31Ge27vh8ojVwBQT4onrxsrtm ahEI7Wi4FDyvtVDaEUxPtEDxAK7wIps1GrLaxEUvXAC8oQJdFdNwKPK8RxQ4Xrsmh47z FFLFLIpL/j70Nb7LG10XTm5t70O12d0D38hftAMwoJdxhlixB4mBWLHQrnOyPpMitfMf C8sQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=bombadil.20170209 header.b=WrBfxKrf; spf=pass (google.com: best guess record for domain of peterz@infradead.org designates 198.137.202.133 as permitted sender) smtp.mailfrom=peterz@infradead.org Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=bombadil.20170209 header.b=WrBfxKrf; spf=pass (google.com: best guess record for domain of peterz@infradead.org designates 198.137.202.133 as permitted sender) smtp.mailfrom=peterz@infradead.org Date: Wed, 14 Mar 2018 11:35:37 +0100 From: Peter Zijlstra To: Thomas Garnier Cc: Herbert Xu , "David S . Miller" , Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , Josh Poimboeuf , Greg Kroah-Hartman , Kate Stewart , Arnd Bergmann , Philippe Ombredanne , Arnaldo Carvalho de Melo , Andrey Ryabinin , Matthias Kaehlcke , Kees Cook , Tom Lendacky , "Kirill A . Shutemov" , Andy Lutomirski , Dominik Brodowski , Borislav Petkov , Borislav Petkov , "Rafael J . Wysocki" , Len Brown , Pavel Machek , Juergen Gross , Alok Kataria , Steven Rostedt , Tejun Heo , Christoph Lameter , Dennis Zhou , Boris Ostrovsky , David Woodhouse , Alexey Dobriyan , "Paul E . McKenney" , Andrew Morton , Nicolas Pitre , Randy Dunlap , "Luis R . Rodriguez" , Christopher Li , Jason Baron , Ashish Kalra , Kyle McMartin , Dou Liyang , Lukas Wunner , Petr Mladek , Sergey Senozhatsky , Masahiro Yamada , Ingo Molnar , Nicholas Piggin , Cao jin , "H . J . Lu" , Paolo Bonzini , Radim =?utf-8?B?S3LEjW3DocWZ?= , Joerg Roedel , Dave Hansen , Rik van Riel , Jia Zhang , Jiri Slaby , Kyle Huey , Jonathan Corbet , Matthew Wilcox , Michal Hocko , Rob Landley , Baoquan He , Daniel Micay , Jan H =?iso-8859-1?Q?=2E_Sch=F6nherr?= , x86@kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, virtualization@lists.linux-foundation.org, xen-devel@lists.xenproject.org, linux-arch@vger.kernel.org, linux-sparse@vger.kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, kernel-hardening@lists.openwall.com Subject: Re: [PATCH v2 21/27] x86/ftrace: Adapt function tracing for PIE support Message-ID: <20180314103537.GR4043@hirez.programming.kicks-ass.net> References: <20180313205945.245105-1-thgarnie@google.com> <20180313205945.245105-22-thgarnie@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180313205945.245105-22-thgarnie@google.com> User-Agent: Mutt/1.9.3 (2018-01-21) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1594858062425792867?= X-GMAIL-MSGID: =?utf-8?q?1594909015412706925?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On Tue, Mar 13, 2018 at 01:59:39PM -0700, Thomas Garnier wrote: > + /* > + * If PIE is not enabled or no GOT call was found, default to the > + * original approach to code modification. > + */ > + if (!IS_ENABLED(CONFIG_X86_PIE) > + || probe_kernel_read(replaced, (void *)ip, sizeof(replaced)) > + || memcmp(replaced, got_call_preinsn, sizeof(got_call_preinsn))) > + return ftrace_modify_code_direct(ip, old_code, new_code); The predominant kernel style is to place the operators at the end of the previous line, not first on the new line.