From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/9541 Path: news.gmane.org!not-for-mail From: Andy Lutomirski Newsgroups: gmane.linux.lib.musl.general,gmane.linux.kernel Subject: Re: [RFC PATCH] x86/vdso/32: Add AT_SYSINFO cancellation helpers Date: Wed, 9 Mar 2016 13:19:45 -0800 Message-ID: References: <06079088639eddd756e2092b735ce4a682081308.1457486598.git.luto@kernel.org> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Trace: ger.gmane.org 1457558424 22884 80.91.229.3 (9 Mar 2016 21:20:24 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 9 Mar 2016 21:20:24 +0000 (UTC) Cc: X86 ML , "linux-kernel@vger.kernel.org" , Borislav Petkov , "musl@lists.openwall.com" To: Andy Lutomirski Original-X-From: musl-return-9554-gllmg-musl=m.gmane.org@lists.openwall.com Wed Mar 09 22:20:24 2016 Return-path: Envelope-to: gllmg-musl@m.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by plane.gmane.org with smtp (Exim 4.69) (envelope-from ) id 1adlWp-0000v7-6q for gllmg-musl@m.gmane.org; Wed, 09 Mar 2016 22:20:23 +0100 Original-Received: (qmail 29843 invoked by uid 550); 9 Mar 2016 21:20:20 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Original-Received: (qmail 29798 invoked from network); 9 Mar 2016 21:20:16 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amacapital-net.20150623.gappssmtp.com; s=20150623; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=mjP6SikG6jsJkK5IUNrRiAFkU2YtP1JryAO3h4iZFtw=; b=h/+dxOL6JVsVatJhG3qitIpHA6N649HL3aOy6qZMlS2aXHQ6UvflWU2czk9R7FWQBb YqWtzcLL0z70Bo1Glzf0p6Lqz9vFUFrdhhdI1jAM0UgSGIaLEe+UzG/rwoXJ96R7kJKk 7MVH4ycq7ta3pY79NNHEV62AFnaKPIFfVdzMGIB/n3WFq429+3psvYpi/cTpQjjaUS5N WDJucKAIs/LqYcpWjNTBFM3ysYcyFJzI4DfU6admS2QO7rOKQsNKCfel9eE2E2AYU99A bhB7fCik/41Ijxeb+6gc9dwxRDPGIKkyzJFf9MxFooT2ahxT77lEoBuDbYtt4Akkacds IkOw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=mjP6SikG6jsJkK5IUNrRiAFkU2YtP1JryAO3h4iZFtw=; b=NkyLbMbW42uNgbJ6aUzcF6HSfBX0pX57lDEevoOEukbaFFlgt6u+I2cn39dE3D4fnp l3f2zYHzIG1YG/LYBpEBY8ctR2spwjTKI0DzKHB+7XEcdhYs/+4403SfHvYj3wxgropG Jds67OUrUO6EAY3Mhav1OE/cmhQyXdjE53DIXKlZqbfY/ApD+yvLLtOqjxRU1hYQby98 0EAtq3NNx+7cYyWHuTqn91ZEy0p9Isu9587MTH5JHI8vMtQqpnvHqu0r0Uae1bL2DYmh /CGf6+9IW9a2SzvdnYOYiZHsisw0F3BUPqO6eS/gN2I4FPQ3Gr8pOgU85yWgsWzZW1Nb yIXA== X-Gm-Message-State: AD7BkJILx+bVAIOb8LzJjvpjSnC2el2wFvQToxJPm0N7cZH0bG4jWDI0kLHFCmuAAyD2cQWuCJCiXgKGgxMqzfar X-Received: by 10.202.72.7 with SMTP id v7mr247023oia.9.1457558404754; Wed, 09 Mar 2016 13:20:04 -0800 (PST) In-Reply-To: Xref: news.gmane.org gmane.linux.lib.musl.general:9541 gmane.linux.kernel:2173414 Archived-At: On Wed, Mar 9, 2016 at 9:58 AM, Andy Lutomirski wrote: > On Tue, Mar 8, 2016 at 5:24 PM, Andy Lutomirski wrote: >> musl implements system call cancellation in an unusual but clever way. >> When a thread issues a cancellable syscall, musl issues the syscall >> through a special thunk that looks roughly like this: >> > > FWIW, this patch fails disastrously on 64-bit kernels. I fixed it, > but it needs kbuild changes. I'll send those out to the maintainers. This version should be okay: https://git.kernel.org/cgit/linux/kernel/git/luto/linux.git/commit/?h=x86/vdso&id=fed6d35d3941bc53896ab80b5c8d68d54cc00347 You'll need the parent, too, if you want to test. I'm going to give the 0day bot a good long chew, since the parent change is a little bit scary. --Andy