From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ingo Molnar Subject: Re: [PATCH] [v4] x86, pkeys: fix siginfo ABI breakage from new field Date: Thu, 3 Mar 2016 16:41:04 +0100 Message-ID: <20160303154104.GA18424@gmail.com> References: <20160301125451.02C7426D@viggo.jf.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-wm0-f67.google.com ([74.125.82.67]:35381 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751272AbcCCPlI (ORCPT ); Thu, 3 Mar 2016 10:41:08 -0500 Content-Disposition: inline In-Reply-To: <20160301125451.02C7426D@viggo.jf.intel.com> Sender: linux-next-owner@vger.kernel.org List-ID: To: Dave Hansen Cc: linux-kernel@vger.kernel.org, dave.hansen@linux.intel.com, sfr@canb.auug.org.au, akpm@linux-foundation.org, tglx@linutronix.de, mingo@elte.hu, hpa@zytor.com, peterz@infradead.org, linux-next@vger.kernel.org, deller@gmx.de * Dave Hansen wrote: > To fix this, we replace the u64 with an '__u32'. The __u32 is guaranteed to > union well with the pointers from _addr_bnd. It is also plenty large enough to > store the 16-bit pkey we have today on x86. The 'union well' sentence is really a leftover from the earlier changelog (the problem was never about interaction between union members) - a better explantion is: > To fix this, we replace the u64 with an '__u32'. The __u32 does not change the > minimum alignment requirements of the structure and it is also plenty large > enough to store the 16-bit pkey we have today on x86. I fixed this up locally, no need to resend. Thanks, Ingo