From owner-freebsd-arm@freebsd.org Fri Sep 8 15:18:35 2017 Return-Path: Delivered-To: freebsd-arm@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 97337E1D65F for ; Fri, 8 Sep 2017 15:18:35 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: from mail-it0-x234.google.com (mail-it0-x234.google.com [IPv6:2607:f8b0:4001:c0b::234]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 68D93833E8 for ; Fri, 8 Sep 2017 15:18:35 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: by mail-it0-x234.google.com with SMTP id v19so2390833ite.0 for ; Fri, 08 Sep 2017 08:18:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bsdimp-com.20150623.gappssmtp.com; s=20150623; h=mime-version:sender:from:date:message-id:subject:to; bh=5pAUfT1nUEu8fPNODKu415H5WehzigOj6KichZPZLV8=; b=ftYPz8JSpqan9pXIJeGPywBEtb7rwyXJEM1hQysEMLOyrFzduMGhHymwKdIgINgYhD sQrdv2UoNuh8JL3PwIAMy5GNj+UpLsihzmapjMbWbN+lIcp1u6O1PgNZadsNtghUunxf PguaUrHY7gWmismSrbpuavshQ6qUDs13owX5iZIW6OA+EEmQlJPAbDm4F6+x/vo8h2es ouTsUNlcoeXTz18UnbCgwiN4Pq8BZN+YZt44wZEzIJ5aG6jnLiVVzUKNflOPiwwjxhDa 9vkABP6aH3o4voLhMwY59pCItw4mRHypfYjOcLpOIUgQ1nYlToFtZkXdzeaW1ogbsK3L 7WxQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:sender:from:date:message-id:subject :to; bh=5pAUfT1nUEu8fPNODKu415H5WehzigOj6KichZPZLV8=; b=nEKfIlzdc8RrD0CRxFpJhuF3sITTwE6WXMmEHMk3wpUwW5aO5ReSlza4URWYT7Ti3c /8vtjg7lpIVtzTVxchlp8evPY2AQTKS9TtMNhSjeITGFhOW9e4Dr9lv/0IJaVE8nmYpj /n3u4me/QG7mco54e9SPEfj6tU9uMk0THBDfk65IbFG74GFduCoLC+4OkMCsyKzU/n+B ATSFdZruN5EwCsoppxlJNnMozVJMDZkT8bqkjxYuZQog/2LTkP9YpodtDNgM/9kPV3UD JP096yIxBO9hGeksC4rREwBG50DnhEV2WNFgkxhgYsTqKIBesPIOcb5Vq+qDOzoADjXf WRwA== X-Gm-Message-State: AHPjjUj2T2s+Jqgxh3phCBpIkqXy/TzuRkx4CFCwhFtTUhTEE7PdZF1R 0JRYya+gSRWpRZpp0RBrHoG/XCr2kcnS9sc= X-Google-Smtp-Source: AOwi7QC+qAfWscolJiF3joL4fjP70+3y7PpD88kf8kiDEPN5A29NHtmU89FdHACgty4dGp9YqLf+7jI3CR4ZpefB5Gg= X-Received: by 10.36.150.198 with SMTP id z189mr1365376itd.63.1504883914182; Fri, 08 Sep 2017 08:18:34 -0700 (PDT) MIME-Version: 1.0 Sender: wlosh@bsdimp.com Received: by 10.79.10.71 with HTTP; Fri, 8 Sep 2017 08:18:33 -0700 (PDT) X-Originating-IP: [2603:300b:6:5100:d5ae:f1f3:42c8:b0f7] From: Warner Losh Date: Fri, 8 Sep 2017 09:18:33 -0600 X-Google-Sender-Auth: 3AOZQCzQWdhbyfo7TTAS_FSzjsE Message-ID: Subject: Heads up To: "freebsd-arm@freebsd.org" Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.23 X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 08 Sep 2017 15:18:35 -0000 Greetings, During the transition from soft to hard float, I made the default behavior of the system as follows: 1. If the binary is hard float use the default ld.so paths 2. if there was no /usr/libsoft directory, use the default ld.so paths 3. otherwise use the soft ld.so paths. which was fine as a transition in a -current environment which has rough edges, but is now causing problems for people trying to execute FreeBSD 10 binaries on FreeBSD 11. I'd like to propose that we eliminate step 2 above so we detect this cross-threading by default. Furthermore, the above algorithm is used, even on armv4/v5 binaries where we can't possibly have hard floating point. I'd further propose that we eliminate the above algorithm altogether for those systems, or more generally when we're compiling for soft floating point. Please see https://reviews.freebsd.org/D12274 to comment on the code. I believe this won't change anybody's FreeBSD experience, unless they have an ld.so compiled for hard float, but every single other binary on the system is somehow soft float. The only time I'm aware of when this happens is when one is jumping the chasm from soft to hard float in an installworld situation, which we can cope with LD_SOFT_ env settings for those that want to jump from 10->current (which I posit may not exist). Comments? Warner