From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x226fszuMN5CjFu5B8KSb1ZESNigW4gE05oPYDPUtJfolvPwpRXUQ/MYlev+CobwIYPGum+20 ARC-Seal: i=1; a=rsa-sha256; t=1518183308; cv=none; d=google.com; s=arc-20160816; b=PJMmpsFxawxMbhY8e76h66CmPLmCQHXVNdxpGguPE6uWnIocv3RPs5+xeOH5xrxHER 0qSKpj8Lnq6MPTiCinPM6f/4wXlHd9gX4bbIeIcuHOUyjHUr1cfDq9Mh18rsCG7UVRBd enGG2IhN39UwyYRWHCi3anzGDcO1nW0NGhFNQDtJ6cuxi0M9vZ2FKwKARPv3W5sblv/T WuUojg2ZJzjb0FtOEOnHU9v5VeYo8BZndEyRTauQ8dUoH7wEjIHUa1+uhrstxA+yJC33 NfMvBfbzhd+/pqPaDLDDXSLAANxKbFdcCHtKw01myiEuav23/sD1Wc/pMqZ7jBUAojuI IYzA== 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=qcqKNoyd5djny+kaoYTMLjCAsRnB8p3C+jm90w4kPl0=; b=Lfezueuw8bJHpLmlJpfqNjFgyoP16yO7UG2pCHuH0I8y21bY1ArLdXtRyZklKe6LRH xyKqlx8IcRTuil47E9D3DRqCDXEluMjHS9AT6wiM7YSLfB2agQFjNT1LAKUGSQ/5GPkf lRWf06RiyhN3NFC11JS6y5hv6s6dl8YDvQqfz+aDiSVUtMkRRRxFoPJybSa4JBJ1/WQk dQ49zHf7RCwttMAoJTIz7lH3DwN/S4eQIYrpB2coMScGbp3EVLlEg4HlBw/LOtoIyLV1 q9417/1+JcFZf5aiQWww+ny8xQdVM23CdILQLZDQo94nHSwkkWVk4xvzH1SQ9Qf0lsbX ofFw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass (test mode) header.i=@8bytes.org header.s=mail-1 header.b=nVQQq6Px; spf=pass (google.com: domain of joro@8bytes.org designates 81.169.241.247 as permitted sender) smtp.mailfrom=joro@8bytes.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=8bytes.org Authentication-Results: mx.google.com; dkim=pass (test mode) header.i=@8bytes.org header.s=mail-1 header.b=nVQQq6Px; spf=pass (google.com: domain of joro@8bytes.org designates 81.169.241.247 as permitted sender) smtp.mailfrom=joro@8bytes.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=8bytes.org Date: Fri, 9 Feb 2018 14:35:07 +0100 From: Joerg Roedel To: Juergen Gross Cc: Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Linus Torvalds , Andy Lutomirski , Dave Hansen , Josh Poimboeuf , Peter Zijlstra , Borislav Petkov , Jiri Kosina , Boris Ostrovsky , Brian Gerst , David Laight , Denys Vlasenko , Eduardo Valentin , Greg KH , Will Deacon , aliguori@amazon.com, daniel.gruss@iaik.tugraz.at, hughd@google.com, keescook@google.com, Andrea Arcangeli , Waiman Long , Pavel Machek , jroedel@suse.de Subject: Re: [PATCH 00/31 v2] PTI support for x86_32 Message-ID: <20180209133507.GD16484@8bytes.org> References: <1518168340-9392-1-git-send-email-joro@8bytes.org> <35f19c79-7277-3ad8-50bf-8def929377b6@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <35f19c79-7277-3ad8-50bf-8def929377b6@suse.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1591914900490843452?= X-GMAIL-MSGID: =?utf-8?q?1591930580926429751?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Hi Juergen, On Fri, Feb 09, 2018 at 01:11:42PM +0100, Juergen Gross wrote: > On 09/02/18 10:25, Joerg Roedel wrote: > > XENPV is also untested from my side, but I added checks to > > not do the stack switches in the entry-code when XENPV is > > enabled, so hopefully it works. But someone should test it, > > of course. > > That's unfortunate. 32 bit XENPV kernel is vulnerable to Meltdown, too. > I'll have a look whether 32 bit XENPV is still working, though. > > Adding support for KPTI with Xen PV should probably be done later. :-) Not sure how much is missing to make it work there, one point is certainly to write the right stack into tss.sp0 for xenpv on 32bit. This write has a check to only happen for !xenpv. But let's first test the code as-is on XENPV and see if it still boots :) Thanks, Joerg