From mboxrd@z Thu Jan 1 00:00:00 1970 From: mans@mansr.com (=?iso-8859-1?Q?M=E5ns_Rullg=E5rd?=) Date: Thu, 03 Jul 2014 23:16:16 +0100 Subject: Android and compatibility with deprecated armv7 instructions In-Reply-To: <20140703173226.GC17372@arm.com> (Will Deacon's message of "Thu, 3 Jul 2014 18:32:26 +0100") References: <20140701234800.GA23577@sirena.org.uk> <20140702100133.GE18731@arm.com> <20140702163923.GJ410@sirena.org.uk> <20140702170141.GH24879@arm.com> <20140703104135.GA28175@arm.com> <20140703170558.GZ32514@n2100.arm.linux.org.uk> <20140703173226.GC17372@arm.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Will Deacon writes: > On Thu, Jul 03, 2014 at 06:05:58PM +0100, Russell King - ARM Linux wrote: >> On Thu, Jul 03, 2014 at 05:22:30PM +0100, Grant Likely wrote: >> > So, no. I completely reject any notion that breaking existing apps is >> > okay. If we're going to say that v8 still supports 32-bit apps, then >> > it has to be all of v7, not just the 'good' bits. Nor do I think >> > saying "it's just a bunch of games" justifies anything. We're kernel >> > engineers. Applications are applications and we don't break userspace. >> > Period. >> >> +1 on all points above. I'd go further - if we're going to say that v8 >> still supports 32-bit apps, that covers at least v6 *as well*. > > We've never pretended to support anything other than ARMv8 in the compat > layer. uname even reports this in the machine name. > > If people are suddenly so concerned about *full* compatibility with an ARMv7 > kernel, that needs a lot more than just SWP emulation: > > - Alignment fixups for ldm/stm No ARM variant ever supported unaligned ldm/stm. -- M?ns Rullg?rd mans at mansr.com