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From: will.deacon@arm.com (Will Deacon)
To: linux-arm-kernel@lists.infradead.org
Subject: Android and compatibility with deprecated armv7 instructions
Date: Wed, 2 Jul 2014 18:01:41 +0100	[thread overview]
Message-ID: <20140702170141.GH24879@arm.com> (raw)
In-Reply-To: <20140702163923.GJ410@sirena.org.uk>

On Wed, Jul 02, 2014 at 05:39:23PM +0100, Mark Brown wrote:
> On Wed, Jul 02, 2014 at 11:01:33AM +0100, Will Deacon wrote:
> 
> >   (1) The hardware doesn't have the instruction at all. If we start
> >       emulating it, then we'll always have to emulate it and it doesn't
> >       encourage software migration.
> 
> That's what the logging other architectures did in similar situations
> was intended to help address - even if people don't care about the
> performance impact having loud complaints in the logs tends to cause
> some useful subset of users to report it as a problem.

I don't think logging something to dmesg is going to make a blind bit of
difference on an Android device. Maybe we could get SWP emulation to request
access to the users contacts and send everybody a text message each time
they issue the instruction?

Seriously though, nothing causes loud complaints like a SIGILL. This thread
is evidence of that.

Will

  reply	other threads:[~2014-07-02 17:01 UTC|newest]

Thread overview: 76+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-07-01 23:06 Android and compatibility with deprecated armv7 instructions Colin Cross
2014-07-01 23:42 ` Olof Johansson
2014-07-01 23:48   ` Mark Brown
2014-07-02 10:01     ` Will Deacon
2014-07-02 15:48       ` Colin Cross
2014-07-02 16:16         ` Will Deacon
2014-07-02 18:03           ` Christopher Covington
2014-07-02 18:25             ` Will Deacon
2014-07-02 19:47               ` Mark Brown
2014-07-05 21:26           ` Rob Herring
2014-07-02 16:39       ` Mark Brown
2014-07-02 17:01         ` Will Deacon [this message]
2014-07-02 17:33           ` Mark Brown
2014-07-02 22:14           ` Grant Likely
2014-07-03 10:41             ` Catalin Marinas
2014-07-03 14:28               ` Arnd Bergmann
2014-07-03 15:00                 ` Russell King - ARM Linux
2014-07-03 15:40                   ` Grant Likely
2014-07-03 17:13                   ` Catalin Marinas
2014-07-03 17:48                     ` Russell King - ARM Linux
2014-07-03 18:15                     ` Arnd Bergmann
2014-07-03 18:30                       ` Russell King - ARM Linux
2014-07-03 18:37                         ` Will Deacon
2014-07-03 18:52                           ` Russell King - ARM Linux
2014-07-03 19:00                             ` Will Deacon
2014-07-04  8:57                         ` Catalin Marinas
2014-07-04  9:25                           ` Russell King - ARM Linux
2014-07-04 10:12                             ` Arnd Bergmann
2014-07-04 14:09                               ` Dr. David Alan Gilbert
2014-07-04 12:56                             ` Grant Likely
2014-07-04 13:31                               ` Russell King - ARM Linux
2014-07-03 18:46                       ` Will Deacon
2014-07-03 18:53                         ` Arnd Bergmann
2014-07-03 19:07                           ` Russell King - ARM Linux
2014-07-03 19:40                             ` Arnd Bergmann
2014-07-04 13:25                     ` Grant Likely
2014-07-03 16:22               ` Grant Likely
2014-07-03 17:05                 ` Russell King - ARM Linux
2014-07-03 17:32                   ` Will Deacon
2014-07-03 18:23                     ` Arnd Bergmann
2014-07-03 18:38                       ` Peter Maydell
2014-07-03 18:40                       ` Will Deacon
2014-07-03 18:32                     ` Mark Brown
2014-07-03 22:16                     ` Måns Rullgård
2014-07-03 22:47                       ` Russell King - ARM Linux
2014-07-04  7:08                         ` Ard Biesheuvel
2014-07-04  8:24                           ` Catalin Marinas
2014-07-04  8:33                             ` Ard Biesheuvel
2014-07-04  9:21                               ` Måns Rullgård
2014-07-04  9:34                                 ` Russell King - ARM Linux
2014-07-04 10:21                                   ` Måns Rullgård
2014-07-04 10:33                                     ` Russell King - ARM Linux
2014-07-04 11:00                                       ` Ard Biesheuvel
2014-07-04 17:28                                         ` Nicolas Pitre
2014-07-03 17:43                 ` Catalin Marinas
2014-07-04 13:22                   ` Grant Likely
2014-07-04 19:24                     ` Mark Brown
2014-07-04 19:33                       ` Arnd Bergmann
2014-07-04 22:06                         ` Måns Rullgård
2014-07-04 22:08                         ` Mark Brown
2014-07-05 11:14                     ` Catalin Marinas
2014-07-05 11:25                       ` Russell King - ARM Linux
2014-07-05 16:43                       ` Mark Brown
2014-07-05 17:06                         ` Catalin Marinas
2014-07-05 18:43                           ` Arnd Bergmann
2014-07-05 21:19                             ` Catalin Marinas
2014-07-06 15:39                               ` Arnd Bergmann
2014-07-07 13:59                                 ` Janne Grunau
2014-07-07 14:52                                   ` Catalin Marinas
2014-07-07 17:52                                     ` Janne Grunau
2014-07-07 15:43                                   ` Peter Maydell
2014-07-08  5:28                                   ` Måns Rullgård
2014-07-07 14:35                                 ` Catalin Marinas
2014-07-07 21:26                                   ` Arnd Bergmann
2014-07-07 12:28                       ` Grant Likely
2014-07-07 18:35                         ` Colin Cross

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