From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f200.google.com (mail-wr0-f200.google.com [209.85.128.200]) by kanga.kvack.org (Postfix) with ESMTP id 81F976B0006 for ; Wed, 21 Feb 2018 05:27:19 -0500 (EST) Received: by mail-wr0-f200.google.com with SMTP id 30so1029402wrw.6 for ; Wed, 21 Feb 2018 02:27:19 -0800 (PST) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id i44sor5202629wri.60.2018.02.21.02.27.17 for (Google Transport Security); Wed, 21 Feb 2018 02:27:18 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20180214085425.GA12779@kroah.com> References: <1518168340-9392-1-git-send-email-joro@8bytes.org> <20180209191112.55zyjf4njum75brd@suse.de> <20180210091543.ynypx4y3koz44g7y@angband.pl> <20180211105909.53bv5q363u7jgrsc@angband.pl> <6FB16384-7597-474E-91A1-1AF09201CEAC@gmail.com> <20180213085429.GB10278@kroah.com> <20180214085425.GA12779@kroah.com> From: Lorenzo Colitti Date: Wed, 21 Feb 2018 19:26:55 +0900 Message-ID: Subject: Re: [PATCH 00/31 v2] PTI support for x86_32 Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-mm@kvack.org List-ID: To: Greg KH Cc: Linus Torvalds , Mark D Rustad , Adam Borowski , Joerg Roedel , Andy Lutomirski , Joerg Roedel , Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , X86 ML , LKML , Linux-MM , Dave Hansen , Josh Poimboeuf , Juergen Gross , Peter Zijlstra , Borislav Petkov , Jiri Kosina , Boris Ostrovsky , Brian Gerst , David Laight , Denys Vlasenko , Eduardo Valentin , Will Deacon , "Liguori, Anthony" , Daniel Gruss , Hugh Dickins , Kees Cook , Andrea Arcangeli , Waiman Long , Pavel Machek , Florian Westphal On Wed, Feb 14, 2018 at 5:54 PM, Greg KH wrote: > > > IPSEC doesn't work with a 64bit kernel and 32bit userspace right now. > > > > > > Back in 2015 someone started to work on that, and properly marked that > > > the kernel could not handle this with commit 74005991b78a ("xfrm: Do not > > > parse 32bits compiled xfrm netlink msg on 64bits host") > > > > > > This is starting to be hit by some Android systems that are moving > > > (yeah, slowly) to 4.4 :( > > > > Does anybody have test-programs/harnesses for this? > > Lorenzo (now on the To: line), is the one that I think is looking into > this, and should have some sort of test for it. Lorenzo? Sorry for the late reply here. The issue is that the xfrm uapi structs don't specify padding at the end, so they're a different size on 32-bit and 64-bit archs. This by itself would be fine, as the kernel could just ignore the (lack of) padding. But some of these structs contain others (e.g., xfrm_userspi_info contains xfrm_usersa_info), and in that case the whole layout after the contained struct is different. On another thread Florian pointed out that he once wrote a patch to fix this - https://patchwork.ozlabs.org/patch/45855/ . Florian, think you could revive that? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org