From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linutronix.de (146.0.238.70:993) by crypto-ml.lab.linutronix.de with IMAP4-SSL for ; 25 Feb 2019 21:04:31 -0000 Received: from mail.kernel.org ([198.145.29.99]) by Galois.linutronix.de with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1gyNQM-0007pK-7B for speck@linutronix.de; Mon, 25 Feb 2019 22:04:30 +0100 Date: Mon, 25 Feb 2019 22:04:21 +0100 From: Greg KH Subject: [MODERATED] Re: [patch V4 05/11] x86/speculation/mds: Clear CPU buffers on exit to user Message-ID: <20190225210421.GD12242@kroah.com> References: <20190222222418.405369026@linutronix.de> <20190222224149.527959429@linutronix.de> MIME-Version: 1.0 In-Reply-To: <20190222224149.527959429@linutronix.de> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit To: speck@linutronix.de List-ID: On Fri, Feb 22, 2019 at 11:24:23PM +0100, speck for Thomas Gleixner wrote: > From: Thomas Gleixner > > Add a static key which controls the invocation of the CPU buffer clear > mechanism on exit to user space and add the call into > prepare_exit_to_usermode() and do_nmi() right before actually returning. > > Add documentation which kernel to user space transition this covers and > explain why some corner cases are not mitigated. > > Signed-off-by: Thomas Gleixner Reviewed-by: Greg Kroah-Hartman